Helper viruses. Medical search

Viruses which enable defective viruses to replicate or to form a protein coat by complementing the missing gene function of the defective (satellite) virus. Helper and satellite may be of the same or different genus.

Viruses which lack a complete genome so that they cannot completely replicate or cannot form a protein coat. Some are host-dependent defectives, meaning they can replicate only in cell systems which provide the particular genetic function which they lack. Others, called SATELLITE VIRUSES, are able to replicate only when their genetic defect is complemented by a helper virus.

The process of intracellular viral multiplication, consisting of the synthesis of PROTEINS; NUCLEIC ACIDS; and sometimes LIPIDS, and their assembly into a new infectious particle.

Small, linear single-stranded RNA molecules functionally acting as molecular parasites of certain RNA plant viruses. Satellite RNAs exhibit four characteristic traits: (1) they require helper viruses to replicate; (2) they are unnecessary for the replication of helper viruses; (3) they are encapsidated in the coat protein of the helper virus; (4) they have no extensive sequence homology to the helper virus. Thus they differ from SATELLITE VIRUSES which encode their own coat protein, and from the genomic RNA; (=RNA, VIRAL); of satellite viruses. (From Maramorosch, Viroids and Satellites, 1991, p143)

Viruses whose genetic material is RNA.

Ribonucleic acid that makes up the genetic material of viruses.

Defective viruses which can multiply only by association with a helper virus which complements the defective gene. Satellite viruses may be associated with certain plant viruses, animal viruses, or bacteriophages. They differ from satellite RNA; (RNA, SATELLITE) in that satellite viruses encode their own coat protein.

The type species of ORTHOPOXVIRUS, related to COWPOX VIRUS, but whose true origin is unknown. It has been used as a live vaccine against SMALLPOX. It is also used as a vector for inserting foreign DNA into animals. Rabbitpox virus is a subspecies of VACCINIA VIRUS.

Viruses parasitic on plants higher than bacteria.

The functional hereditary units of VIRUSES.

The assembly of VIRAL STRUCTURAL PROTEINS and nucleic acid (VIRAL DNA or VIRAL RNA) to form a VIRUS PARTICLE.

A species in the group RETICULOENDOTHELIOSIS VIRUSES, AVIAN of the genus GAMMARETROVIRUS that causes a chronic neoplastic and a more acute immunosuppressive disease in fowl.

Proteins found in any species of virus.

DNA molecules capable of autonomous replication within a host cell and into which other DNA sequences can be inserted and thus amplified. Many are derived from PLASMIDS; BACTERIOPHAGES; or VIRUSES. They are used for transporting foreign genes into recipient cells. Genetic vectors possess a functional replicator site and contain GENETIC MARKERS to facilitate their selective recognition.

Deoxyribonucleic acid that makes up the genetic material of viruses.

A group of replication-defective viruses, in the genus GAMMARETROVIRUS, which are capable of transforming cells, but which replicate and produce tumors only in the presence of Murine leukemia viruses (LEUKEMIA VIRUS, MURINE).

A species of POLYOMAVIRUS originally isolated from Rhesus monkey kidney tissue. It produces malignancy in human and newborn hamster kidney cell cultures.

A strain of Murine leukemia virus (LEUKEMIA VIRUS, MURINE) producing leukemia of the reticulum-cell type with massive infiltration of liver, spleen, and bone marrow. It infects DBA/2 and Swiss mice.

A genus of the family PARVOVIRIDAE, subfamily PARVOVIRINAE, which are dependent on a coinfection with helper adenoviruses or herpesviruses for their efficient replication. The type species is Adeno-associated virus 2.

Specific molecular components of the cell capable of recognizing and interacting with a virus, and which, after binding it, are capable of generating some signal that initiates the chain of events leading to the biological response.

A strain of Murine leukemia virus (LEUKEMIA VIRUS, MURINE) arising during the propagation of S37 mouse sarcoma, and causing lymphoid leukemia in mice. It also infects rats and newborn hamsters. It is apparently transmitted to embryos in utero and to newborns through mother's milk.

Family of RNA viruses that infects birds and mammals and encodes the enzyme reverse transcriptase. The family contains seven genera: DELTARETROVIRUS; LENTIVIRUS; RETROVIRUSES TYPE B, MAMMALIAN; ALPHARETROVIRUS; GAMMARETROVIRUS; RETROVIRUSES TYPE D; and SPUMAVIRUS. A key feature of retrovirus biology is the synthesis of a DNA copy of the genome which is integrated into cellular DNA. After integration it is sometimes not expressed but maintained in a latent state (PROVIRUSES).

Process of growing viruses in live animals, plants, or cultured cells.

Subpopulation of CD4+ lymphocytes that cooperate with other lymphocytes (either T or B) to initiate a variety of immune functions. For example, helper-inducer T-cells cooperate with B-cells to produce antibodies to thymus-dependent antigens and with other subpopulations of T-cells to initiate a variety of cell-mediated immune functions.

Established cell cultures that have the potential to propagate indefinitely.

The expelling of virus particles from the body. Important routes include the respiratory tract, genital tract, and intestinal tract. Virus shedding is an important means of vertical transmission (INFECTIOUS DISEASE TRANSMISSION, VERTICAL).

A general term for diseases produced by viruses.

A phenomenon in which infection by a first virus results in resistance of cells or tissues to infection by a second, unrelated virus.

The type species of ALPHARETROVIRUS producing latent or manifest lymphoid leukosis in fowl.

Viruses whose nucleic acid is DNA.

An inheritable change in cells manifested by changes in cell division and growth and alterations in cell surface properties. It is induced by infection with a transforming virus.

Species of GAMMARETROVIRUS, containing many well-defined strains, producing leukemia in mice. Disease is commonly induced by injecting filtrates of propagable tumors into newborn mice.

The type species of ALPHAVIRUS normally transmitted to birds by CULEX mosquitoes in Egypt, South Africa, India, Malaya, the Philippines, and Australia. It may be associated with fever in humans. Serotypes (differing by less than 17% in nucleotide sequence) include Babanki, Kyzylagach, and Ockelbo viruses.

The type species of MORBILLIVIRUS and the cause of the highly infectious human disease MEASLES, which affects mostly children.

Viruses which produce a mottled appearance of the leaves of plants.

Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.

A genus of RETROVIRIDAE comprising endogenous sequences in mammals, related RETICULOENDOTHELIOSIS VIRUSES, AVIAN, and a reptilian virus. Many species contain oncogenes and cause leukemias and sarcomas.

A subtype of INFLUENZA A VIRUS with the surface proteins hemagglutinin 1 and neuraminidase 1. The H1N1 subtype was responsible for the Spanish flu pandemic of 1918.

The type species of LYSSAVIRUS causing rabies in humans and other animals. Transmission is mostly by animal bites through saliva. The virus is neurotropic multiplying in neurons and myotubes of vertebrates.

A CELL LINE derived from the kidney of the African green (vervet) monkey, (CERCOPITHECUS AETHIOPS) used primarily in virus replication studies and plaque assays.

Substances elaborated by viruses that have antigenic activity.

A subtype of INFLUENZA A VIRUS comprised of the surface proteins hemagglutinin 5 and neuraminidase 1. The H5N1 subtype, frequently referred to as the bird flu virus, is endemic in wild birds and very contagious among both domestic (POULTRY) and wild birds. It does not usually infect humans, but some cases have been reported.

A species of CERCOPITHECUS containing three subspecies: C. tantalus, C. pygerythrus, and C. sabeus. They are found in the forests and savannah of Africa. The African green monkey (C. pygerythrus) is the natural host of SIMIAN IMMUNODEFICIENCY VIRUS and is used in AIDS research.

Production of new arrangements of DNA by various mechanisms such as assortment and segregation, CROSSING OVER; GENE CONVERSION; GENETIC TRANSFORMATION; GENETIC CONJUGATION; GENETIC TRANSDUCTION; or mixed infection of viruses.

Leukemia induced experimentally in animals by exposure to leukemogenic agents, such as VIRUSES; RADIATION; or by TRANSPLANTATION of leukemic tissues.

The infective system of a virus, composed of the viral genome, a protein core, and a protein coat called a capsid, which may be naked or enclosed in a lipoprotein envelope called the peplos.

The type species of TOBAMOVIRUS which causes mosaic disease of tobacco. Transmission occurs by mechanical inoculation.

The type species of the genus ORTHOHEPADNAVIRUS which causes human HEPATITIS B and is also apparently a causal agent in human HEPATOCELLULAR CARCINOMA. The Dane particle is an intact hepatitis virion, named after its discoverer. Non-infectious spherical and tubular particles are also seen in the serum.

A subtype of INFLUENZA A VIRUS comprised of the surface proteins hemagglutinin 3 and neuraminidase 2. The H3N2 subtype was responsible for the Hong Kong flu pandemic of 1968.

A species of FLAVIVIRUS, one of the Japanese encephalitis virus group (ENCEPHALITIS VIRUSES, JAPANESE). It can infect birds and mammals. In humans, it is seen most frequently in Africa, Asia, and Europe presenting as a silent infection or undifferentiated fever (WEST NILE FEVER). The virus appeared in North America for the first time in 1999. It is transmitted mainly by CULEX spp mosquitoes which feed primarily on birds, but it can also be carried by the Asian Tiger mosquito, AEDES albopictus, which feeds mainly on mammals.

A group of viruses in the PNEUMOVIRUS genus causing respiratory infections in various mammals. Humans and cattle are most affected but infections in goats and sheep have also been reported.

A species of GAMMARETROVIRUS causing leukemia, lymphosarcoma, immune deficiency, or other degenerative diseases in cats. Several cellular oncogenes confer on FeLV the ability to induce sarcomas (see also SARCOMA VIRUSES, FELINE).

Acquired defect of cellular immunity that occurs in mice infected with mouse leukemia viruses (MuLV). The syndrome shows striking similarities with human AIDS and is characterized by lymphadenopathy, profound immunosuppression, enhanced susceptibility to opportunistic infections, and B-cell lymphomas.

Any of the processes by which cytoplasmic factors influence the differential control of gene action in viruses.

The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.

A genus of the family RETROVIRIDAE with type C morphology, that causes malignant and other diseases in wild birds and domestic fowl.

The uptake of naked or purified DNA by CELLS, usually meaning the process as it occurs in eukaryotic cells. It is analogous to bacterial transformation (TRANSFORMATION, BACTERIAL) and both are routinely employed in GENE TRANSFER TECHNIQUES.

Extrachromosomal, usually CIRCULAR DNA molecules that are self-replicating and transferable from one organism to another. They are found in a variety of bacterial, archaeal, fungal, algal, and plant species. They are used in GENETIC ENGINEERING as CLONING VECTORS.

The type species of SIMPLEXVIRUS causing most forms of non-genital herpes simplex in humans. Primary infection occurs mainly in infants and young children and then the virus becomes latent in the dorsal root ganglion. It then is periodically reactivated throughout life causing mostly benign conditions.

Infections produced by oncogenic viruses. The infections caused by DNA viruses are less numerous but more diverse than those caused by the RNA oncogenic viruses.

The mechanism by which latent viruses, such as genetically transmitted tumor viruses (PROVIRUSES) or PROPHAGES of lysogenic bacteria, are induced to replicate and then released as infectious viruses. It may be effected by various endogenous and exogenous stimuli, including B-cell LIPOPOLYSACCHARIDES, glucocorticoid hormones, halogenated pyrimidines, IONIZING RADIATION, ultraviolet light, and superinfecting viruses.

A genus of the family HERPESVIRIDAE, subfamily ALPHAHERPESVIRINAE, consisting of herpes simplex-like viruses. The type species is HERPESVIRUS 1, HUMAN.

Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.

A satellite RNA (not a satellite virus) which has several types. Different cucumoviruses can act as helper viruses for different types.

A family of non-enveloped viruses infecting mammals (MASTADENOVIRUS) and birds (AVIADENOVIRUS) or both (ATADENOVIRUS). Infections may be asymptomatic or result in a variety of diseases.

The type species of VESICULOVIRUS causing a disease symptomatically similar to FOOT-AND-MOUTH DISEASE in cattle, horses, and pigs. It may be transmitted to other species including humans, where it causes influenza-like symptoms.

The outer protein protective shell of a virus, which protects the viral nucleic acid.

A genus of plant viruses of the family BROMOVIRIDAE, which infect cucurbits and solanaceous plants. Transmission occurs via aphids in a non-persistent manner, and also via seeds. The type species Cucumber mosaic virus, a CUCUMOVIRUS, should not be confused with Cucumber green mottle mosaic virus, a TOBAMOVIRUS.

A plant genus of the family SOLANACEAE. Members contain NICOTINE and other biologically active chemicals; its dried leaves are used for SMOKING.

Insertion of viral DNA into host-cell DNA. This includes integration of phage DNA into bacterial DNA; (LYSOGENY); to form a PROPHAGE or integration of retroviral DNA into cellular DNA to form a PROVIRUS.

Visible morphologic changes in cells infected with viruses. It includes shutdown of cellular RNA and protein synthesis, cell fusion, release of lysosomal enzymes, changes in cell membrane permeability, diffuse changes in intracellular structures, presence of viral inclusion bodies, and chromosomal aberrations. It excludes malignant transformation, which is CELL TRANSFORMATION, VIRAL. Viral cytopathogenic effects provide a valuable method for identifying and classifying the infecting viruses.

Membrane glycoproteins from influenza viruses which are involved in hemagglutination, virus attachment, and envelope fusion. Fourteen distinct subtypes of HA glycoproteins and nine of NA glycoproteins have been identified from INFLUENZA A VIRUS; no subtypes have been identified for Influenza B or Influenza C viruses.

The ability of a pathogenic virus to lie dormant within a cell (latent infection). In eukaryotes, subsequent activation and viral replication is thought to be caused by extracellular stimulation of cellular transcription factors. Latency in bacteriophage is maintained by the expression of virally encoded repressors.

A replication-defective strain of Murine leukemia virus (LEUKEMIA VIRUS, MURINE) capable of transforming lymphoid cells and producing a rapidly progressing lymphoid leukemia after superinfection with FRIEND MURINE LEUKEMIA VIRUS; MOLONEY MURINE LEUKEMIA VIRUS; or RAUSCHER VIRUS.

Viruses that produce tumors.

The complete genetic complement contained in a DNA or RNA molecule in a virus.

Species of the genus LENTIVIRUS, subgenus primate immunodeficiency viruses (IMMUNODEFICIENCY VIRUSES, PRIMATE), that induces acquired immunodeficiency syndrome in monkeys and apes (SAIDS). The genetic organization of SIV is virtually identical to HIV.

The biosynthesis of RNA carried out on a template of DNA. The biosynthesis of DNA from an RNA template is called REVERSE TRANSCRIPTION.

Inoculation of a series of animals or in vitro tissue with an infectious bacterium or virus, as in VIRULENCE studies and the development of vaccines.

A species of GAMMARETROVIRUS producing tumors in primates. Originally isolated from a fibrosarcoma in a woolly monkey, WMSV is a replication-defective v-onc virus which carries the sis oncogene. In order to propagate, WMSV requires a replication-competent helper virus.

Widely used technique which exploits the ability of complementary sequences in single-stranded DNAs or RNAs to pair with each other to form a double helix. Hybridization can take place between two complimentary DNA sequences, between a single-stranded DNA and a complementary RNA, or between two RNA sequences. The technique is used to detect and isolate specific sequences, measure homology, or define other characteristics of one or both strands. (Kendrew, Encyclopedia of Molecular Biology, 1994, p503)

A species of RESPIROVIRUS also called hemadsorption virus 2 (HA2), which causes laryngotracheitis in humans, especially children.

Strains of MURINE LEUKEMIA VIRUS that are replication-defective and rapidly transforming. The envelope gene plays an essential role in initiating erythroleukemia (LEUKEMIA, ERYTHROBLASTIC, ACUTE), manifested by splenic foci, SPLENOMEGALY, and POLYCYTHEMIA. Spleen focus-forming viruses are generated by recombination with endogenous retroviral sequences.

The type species of RUBULAVIRUS that causes an acute infectious disease in humans, affecting mainly children. Transmission occurs by droplet infection.

Biologically active DNA which has been formed by the in vitro joining of segments of DNA from different sources. It includes the recombination joint or edge of a heteroduplex region where two recombining DNA molecules are connected.

The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.

A species of ALPHAVIRUS isolated in central, eastern, and southern Africa.

Subset of helper-inducer T-lymphocytes which synthesize and secrete the interleukins IL-4, IL-5, IL-6, and IL-10. These cytokines influence B-cell development and antibody production as well as augmenting humoral responses.

Plants or plant parts which are harmful to man or other animals.

In vitro method for producing large amounts of specific DNA or RNA fragments of defined length and sequence from small amounts of short oligonucleotide flanking sequences (primers). The essential steps include thermal denaturation of the double-stranded target molecules, annealing of the primers to their complementary sequences, and extension of the annealed primers by enzymatic synthesis with DNA polymerase. The reaction is efficient, specific, and extremely sensitive. Uses for the reaction include disease diagnosis, detection of difficult-to-isolate pathogens, mutation analysis, genetic testing, DNA sequencing, and analyzing evolutionary relationships.

The measurement of infection-blocking titer of ANTISERA by testing a series of dilutions for a given virus-antiserum interaction end-point, which is generally the dilution at which tissue cultures inoculated with the serum-virus mixtures demonstrate cytopathology (CPE) or the dilution at which 50% of test animals injected with serum-virus mixtures show infectivity (ID50) or die (LD50).

Diseases of plants.

Group of alpharetroviruses (ALPHARETROVIRUS) producing sarcomata and other tumors in chickens and other fowl and also in pigeons, ducks, and RATS.

A species in the genus HEPATOVIRUS containing one serotype and two strains: HUMAN HEPATITIS A VIRUS and Simian hepatitis A virus causing hepatitis in humans (HEPATITIS A) and primates, respectively.

Method for measuring viral infectivity and multiplication in CULTURED CELLS. Clear lysed areas or plaques develop as the VIRAL PARTICLES are released from the infected cells during incubation. With some VIRUSES, the cells are killed by a cytopathic effect; with others, the infected cells are not killed but can be detected by their hemadsorptive ability. Sometimes the plaque cells contain VIRAL ANTIGENS which can be measured by IMMUNOFLUORESCENCE.

A defective virus, containing particles of RNA nucleoprotein in virion-like form, present in patients with acute hepatitis B and chronic hepatitis. It requires the presence of a hepadnavirus for full replication. This is the lone species in the genus Deltavirus.

Agents used in the prophylaxis or therapy of VIRUS DISEASES. Some of the ways they may act include preventing viral replication by inhibiting viral DNA polymerase; binding to specific cell-surface receptors and inhibiting viral penetration or uncoating; inhibiting viral protein synthesis; or blocking late stages of virus assembly.

A subfamily in the family MURIDAE, comprising the hamsters. Four of the more common genera are Cricetus, CRICETULUS; MESOCRICETUS; and PHODOPUS.

The process by which a DNA molecule is duplicated.

Duplex DNA sequences in eukaryotic chromosomes, corresponding to the genome of a virus, that are transmitted from one cell generation to the next without causing lysis of the host. Proviruses are often associated with neoplastic cell transformation and are key features of retrovirus biology.

A plant genus of the family POACEAE. The seed is one of the EDIBLE GRAINS used in millet cereals and in feed for birds and livestock (ANIMAL FEED). It contains diosgenin (SAPONINS).

Lymphocytes responsible for cell-mediated immunity. Two types have been identified - cytotoxic (T-LYMPHOCYTES, CYTOTOXIC) and helper T-lymphocytes (T-LYMPHOCYTES, HELPER-INDUCER). They are formed when lymphocytes circulate through the THYMUS GLAND and differentiate to thymocytes. When exposed to an antigen, they divide rapidly and produce large numbers of new T cells sensitized to that antigen.

An encapsulated lymphatic organ through which venous blood filters.

The binding of virus particles to receptors on the host cell surface. For enveloped viruses, the virion ligand is usually a surface glycoprotein as is the cellular receptor. For non-enveloped viruses, the virus CAPSID serves as the ligand.

A species of POLYOMAVIRUS apparently infecting over 90% of children but not clearly associated with any clinical illness in childhood. The virus remains latent in the body throughout life and can be reactivated under certain circumstances.

A family of RNA viruses causing INFLUENZA and other diseases. There are five recognized genera: INFLUENZAVIRUS A; INFLUENZAVIRUS B; INFLUENZAVIRUS C; ISAVIRUS; and THOGOTOVIRUS.

Viruses whose taxonomic relationships have not been established.

A species of POLYOMAVIRUS, originally isolated from the brain of a patient with progressive multifocal leukoencephalopathy. The patient's initials J.C. gave the virus its name. Infection is not accompanied by any apparent illness but serious demyelinating disease can appear later, probably following reactivation of latent virus.

The first continuously cultured human malignant CELL LINE, derived from the cervical carcinoma of Henrietta Lacks. These cells are used for VIRUS CULTIVATION and antitumor drug screening assays.

Subset of helper-inducer T-lymphocytes which synthesize and secrete interleukin-2, gamma-interferon, and interleukin-12. Due to their ability to kill antigen-presenting cells and their lymphokine-mediated effector activity, Th1 cells are associated with vigorous delayed-type hypersensitivity reactions.

Virus diseases caused by the ORTHOMYXOVIRIDAE.

The developmental entity of a fertilized chicken egg (ZYGOTE). The developmental process begins about 24 h before the egg is laid at the BLASTODISC, a small whitish spot on the surface of the EGG YOLK. After 21 days of incubation, the embryo is fully developed before hatching.

Common name for the species Gallus gallus, the domestic fowl, in the family Phasianidae, order GALLIFORMES. It is descended from the red jungle fowl of SOUTHEAST ASIA.

The introduction of functional (usually cloned) GENES into cells. A variety of techniques and naturally occurring processes are used for the gene transfer such as cell hybridization, LIPOSOMES or microcell-mediated gene transfer, ELECTROPORATION, chromosome-mediated gene transfer, TRANSFECTION, and GENETIC TRANSDUCTION. Gene transfer may result in genetically transformed cells and individual organisms.

The relationships of groups of organisms as reflected by their genetic makeup.

Proteins coded by the retroviral gag gene. The products are usually synthesized as protein precursors or POLYPROTEINS, which are then cleaved by viral proteases to yield the final products. Many of the final products are associated with the nucleoprotein core of the virion. gag is short for group-specific antigen.

The transfer of bacterial DNA by phages from an infected bacterium to another bacterium. This also refers to the transfer of genes into eukaryotic cells by viruses. This naturally occurring process is routinely employed as a GENE TRANSFER TECHNIQUE.

The type species of ORBIVIRUS causing a serious disease in sheep, especially lambs. It may also infect wild ruminants and other domestic animals.

DNA sequences that form the coding region for proteins associated with the viral core in retroviruses. gag is short for group-specific antigen.

Short sequences (generally about 10 base pairs) of DNA that are complementary to sequences of messenger RNA and allow reverse transcriptases to start copying the adjacent sequences of mRNA. Primers are used extensively in genetic and molecular biology techniques.

A myeloproliferative disorder characterized by neoplastic proliferation of erythroblastic and myeloblastic elements with atypical erythroblasts and myeloblasts in the peripheral blood.

The restriction of a characteristic behavior, anatomical structure or physical system, such as immune response; metabolic response, or gene or gene variant to the members of one species. It refers to that property which differentiates one species from another but it is also used for phylogenetic levels higher or lower than the species.

The type species of RESPIROVIRUS in the subfamily PARAMYXOVIRINAE. It is the murine version of HUMAN PARAINFLUENZA VIRUS 1, distinguished by host range.

The protoplasm and plasma membrane of plant, fungal, bacterial or archaeon cells without the CELL WALL.

A critical subpopulation of T-lymphocytes involved in the induction of most immunological functions. The HIV virus has selective tropism for the T4 cell which expresses the CD4 phenotypic marker, a receptor for HIV. In fact, the key element in the profound immunosuppression seen in HIV infection is the depletion of this subset of T-lymphocytes.

Sequences of DNA or RNA that occur in multiple copies. There are several types: INTERSPERSED REPETITIVE SEQUENCES are copies of transposable elements (DNA TRANSPOSABLE ELEMENTS or RETROELEMENTS) dispersed throughout the genome. TERMINAL REPEAT SEQUENCES flank both ends of another sequence, for example, the long terminal repeats (LTRs) on RETROVIRUSES. Variations may be direct repeats, those occurring in the same direction, or inverted repeats, those opposite to each other in direction. TANDEM REPEAT SEQUENCES are copies which lie adjacent to each other, direct or inverted (INVERTED REPEAT SEQUENCES).

The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.

Deletion of sequences of nucleic acids from the genetic material of an individual.

Cell changes manifested by escape from control mechanisms, increased growth potential, alterations in the cell surface, karyotypic abnormalities, morphological and biochemical deviations from the norm, and other attributes conferring the ability to invade, metastasize, and kill.

Pneumovirus infections caused by the RESPIRATORY SYNCYTIAL VIRUSES. Humans and cattle are most affected but infections in goats and sheep have been reported.

Morphologic alteration of small B LYMPHOCYTES or T LYMPHOCYTES in culture into large blast-like cells able to synthesize DNA and RNA and to divide mitotically. It is induced by INTERLEUKINS; MITOGENS such as PHYTOHEMAGGLUTININS, and by specific ANTIGENS. It may also occur in vivo as in GRAFT REJECTION.

Enzymes that are part of the restriction-modification systems. They catalyze the endonucleolytic cleavage of DNA sequences which lack the species-specific methylation pattern in the host cell's DNA. Cleavage yields random or specific double-stranded fragments with terminal 5'-phosphates. The function of restriction enzymes is to destroy any foreign DNA that invades the host cell. Most have been studied in bacterial systems, but a few have been found in eukaryotic organisms. They are also used as tools for the systematic dissection and mapping of chromosomes, in the determination of base sequences of DNAs, and have made it possible to splice and recombine genes from one organism into the genome of another. EC 3.21.1.

The type species of the FLAVIVIRUS genus. Principal vector transmission to humans is by AEDES spp. mosquitoes.

Genes whose gain-of-function alterations lead to NEOPLASTIC CELL TRANSFORMATION. They include, for example, genes for activators or stimulators of CELL PROLIFERATION such as growth factors, growth factor receptors, protein kinases, signal transducers, nuclear phosphoproteins, and transcription factors. A prefix of "v-" before oncogene symbols indicates oncogenes captured and transmitted by RETROVIRUSES; the prefix "c-" before the gene symbol of an oncogene indicates it is the cellular homolog (PROTO-ONCOGENES) of a v-oncogene.

The type species of LEPORIPOXVIRUS causing infectious myxomatosis, a severe generalized disease, in rabbits. Tumors are not always present.

Inactivation of viruses by non-immune related techniques. They include extremes of pH, HEAT treatment, ultraviolet radiation, IONIZING RADIATION; DESICCATION; ANTISEPTICS; DISINFECTANTS; organic solvents, and DETERGENTS.

A species of ORTHOPOXVIRUS that is the etiologic agent of COWPOX. It is closely related to but antigenically different from VACCINIA VIRUS.

RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.

A species of ORTHOPOXVIRUS causing infections in humans. No infections have been reported since 1977 and the virus is now believed to be virtually extinct.

A genus of plant viruses that infects ANGIOSPERMS. Transmission occurs mechanically and through soil, with one species transmitted via a fungal vector. The type species is Tomato bushy stunt virus.

The type species of PNEUMOVIRUS and an important cause of lower respiratory disease in infants and young children. It frequently presents with bronchitis and bronchopneumonia and is further characterized by fever, cough, dyspnea, wheezing, and pallor.

A species of ARENAVIRUS, part of the Old World Arenaviruses (ARENAVIRUSES, OLD WORLD), and the etiologic agent of LASSA FEVER. LASSA VIRUS is a common infective agent in humans in West Africa. Its natural host is the multimammate mouse Mastomys natalensis.

Sites on an antigen that interact with specific antibodies.

The spatial arrangement of the atoms of a nucleic acid or polynucleotide that results in its characteristic 3-dimensional shape.

An acute viral infection in humans involving the respiratory tract. It is marked by inflammation of the NASAL MUCOSA; the PHARYNX; and conjunctiva, and by headache and severe, often generalized, myalgia.

A species of ALPHAVIRUS causing an acute dengue-like fever.

The type species in the genus NOROVIRUS, first isolated in 1968 from the stools of school children in Norwalk, Ohio, who were suffering from GASTROENTERITIS. The virions are non-enveloped spherical particles containing a single protein. Multiple strains are named after the places where outbreaks have occurred.

Lymphoid cells concerned with humoral immunity. They are short-lived cells resembling bursa-derived lymphocytes of birds in their production of immunoglobulin upon appropriate stimulation.

Proteins that form the CAPSID of VIRUSES.

Techniques and strategies which include the use of coding sequences and other conventional or radical means to transform or modify cells for the purpose of treating or reversing disease conditions.

Includes the spectrum of human immunodeficiency virus infections that range from asymptomatic seropositivity, thru AIDS-related complex (ARC), to acquired immunodeficiency syndrome (AIDS).

A collection of single-stranded RNA viruses scattered across the Bunyaviridae, Flaviviridae, and Togaviridae families whose common property is the ability to induce encephalitic conditions in infected hosts.

A genus of FLAVIVIRIDAE causing parenterally-transmitted HEPATITIS C which is associated with transfusions and drug abuse. Hepatitis C virus is the type species.

The type species of LYMPHOCRYPTOVIRUS, subfamily GAMMAHERPESVIRINAE, infecting B-cells in humans. It is thought to be the causative agent of INFECTIOUS MONONUCLEOSIS and is strongly associated with oral hairy leukoplakia (LEUKOPLAKIA, HAIRY;), BURKITT LYMPHOMA; and other malignancies.

A strain of MURINE LEUKEMIA VIRUS associated with mouse tumors similar to those caused by the FRIEND MURINE LEUKEMIA VIRUS. It is a replication-competent murine leukemia virus. It can act as a helper virus when complexing with a defective transforming component, RAUSCHER SPLEEN FOCUS-FORMING VIRUS.

Viral proteins that are components of the mature assembled VIRUS PARTICLES. They may include nucleocapsid core proteins (gag proteins), enzymes packaged within the virus particle (pol proteins), and membrane components (env proteins). These do not include the proteins encoded in the VIRAL GENOME that are produced in infected cells but which are not packaged in the mature virus particle,i.e. the so called non-structural proteins (VIRAL NONSTRUCTURAL PROTEINS).

Biological properties, processes, and activities of VIRUSES.

Infection with human herpesvirus 4 (HERPESVIRUS 4, HUMAN); which may facilitate the development of various lymphoproliferative disorders. These include BURKITT LYMPHOMA (African type), INFECTIOUS MONONUCLEOSIS, and oral hairy leukoplakia (LEUKOPLAKIA, HAIRY).

An individual that contains cell populations derived from different zygotes.

Specific hemagglutinin subtypes encoded by VIRUSES.

Directed modification of the gene complement of a living organism by such techniques as altering the DNA, substituting genetic material by means of a virus, transplanting whole nuclei, transplanting cell hybrids, etc.

A subgroup of the genus FLAVIVIRUS that causes encephalitis and hemorrhagic fevers and is found in eastern and western Europe and the former Soviet Union. It is transmitted by TICKS and there is an associated milk-borne transmission from viremic cattle, goats, and sheep.

A species of RESPIROVIRUS frequently isolated from small children with pharyngitis, bronchitis, and pneumonia.

The major interferon produced by mitogenically or antigenically stimulated LYMPHOCYTES. It is structurally different from TYPE I INTERFERON and its major activity is immunoregulation. It has been implicated in the expression of CLASS II HISTOCOMPATIBILITY ANTIGENS in cells that do not normally produce them, leading to AUTOIMMUNE DISEASES.

Use of restriction endonucleases to analyze and generate a physical map of genomes, genes, or other segments of DNA.

A replication-defective murine sarcoma virus (SARCOMA VIRUSES, MURINE) isolated from a rhabdomyosarcoma by Moloney in 1966.

The type species of APHTHOVIRUS, causing FOOT-AND-MOUTH DISEASE in cloven-hoofed animals. Several different serotypes exist.

Immunoglobulins produced in response to VIRAL ANTIGENS.

The degree of pathogenicity within a group or species of microorganisms or viruses as indicated by case fatality rates and/or the ability of the organism to invade the tissues of the host. The pathogenic capacity of an organism is determined by its VIRULENCE FACTORS.

Any DNA sequence capable of independent replication or a molecule that possesses a REPLICATION ORIGIN and which is therefore potentially capable of being replicated in a suitable cell. (Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)

A multistage process that includes cloning, physical mapping, subcloning, determination of the DNA SEQUENCE, and information analysis.

A species of ARTERIVIRUS causing reproductive and respiratory disease in pigs. The European strain is called Lelystad virus. Airborne transmission is common.

Any of the viruses that cause inflammation of the liver. They include both DNA and RNA viruses as well viruses from humans and animals.

Experimentally induced neoplasms of CONNECTIVE TISSUE in animals to provide a model for studying human SARCOMA.

Non-antibody proteins secreted by inflammatory leukocytes and some non-leukocytic cells, that act as intercellular mediators. They differ from classical hormones in that they are produced by a number of tissue or cell types rather than by specialized glands. They generally act locally in a paracrine or autocrine rather than endocrine manner.

A method (first developed by E.M. Southern) for detection of DNA that has been electrophoretically separated and immobilized by blotting on nitrocellulose or other type of paper or nylon membrane followed by hybridization with labeled NUCLEIC ACID PROBES.

A group of ribonucleotides (up to 12) in which the phosphate residues of each ribonucleotide act as bridges in forming diester linkages between the ribose moieties.

Antibodies produced by a single clone of cells.

A strain of PRIMATE T-LYMPHOTROPIC VIRUS 1 isolated from mature T4 cells in patients with T-lymphoproliferation malignancies. It causes adult T-cell leukemia (LEUKEMIA-LYMPHOMA, T-CELL, ACUTE, HTLV-I-ASSOCIATED), T-cell lymphoma (LYMPHOMA, T-CELL), and is involved in mycosis fungoides, SEZARY SYNDROME and tropical spastic paraparesis (PARAPARESIS, TROPICAL SPASTIC).

Proteins found mainly in icosahedral DNA and RNA viruses. They consist of proteins directly associated with the nucleic acid inside the NUCLEOCAPSID.

Tumor-selective, replication competent VIRUSES that have antineoplastic effects. This is achieved by producing cytotoxicity-enhancing proteins and/or eliciting an antitumor immune response. They are genetically engineered so that they can replicate in CANCER cells but not in normal cells, and are used in ONCOLYTIC VIROTHERAPY.

The type species of PARAPOXVIRUS which causes a skin infection in natural hosts, usually young sheep. Humans may contract local skin lesions by contact. The virus apparently persists in soil.

A group of viruses in the genus PESTIVIRUS, causing diarrhea, fever, oral ulcerations, hemorrhagic syndrome, and various necrotic lesions among cattle and other domestic animals. The two species (genotypes), BVDV-1 and BVDV-2 , exhibit antigenic and pathological differences. The historical designation, BVDV, consisted of both (then unrecognized) genotypes.

A suborder of PRIMATES consisting of six families: CEBIDAE (some New World monkeys), ATELIDAE (some New World monkeys), CERCOPITHECIDAE (Old World monkeys), HYLOBATIDAE (gibbons and siamangs), CALLITRICHINAE (marmosets and tamarins), and HOMINIDAE (humans and great apes).

A soluble factor produced by activated T-LYMPHOCYTES that induces the expression of MHC CLASS II GENES and FC RECEPTORS on B-LYMPHOCYTES and causes their proliferation and differentiation. It also acts on T-lymphocytes, MAST CELLS, and several other hematopoietic lineage cells.

A positive-stranded RNA virus species in the genus HEPEVIRUS, causing enterically-transmitted non-A, non-B hepatitis (HEPATITIS E).

The production of ANTIBODIES by proliferating and differentiated B-LYMPHOCYTES under stimulation by ANTIGENS.

An immunoassay utilizing an antibody labeled with an enzyme marker such as horseradish peroxidase. While either the enzyme or the antibody is bound to an immunosorbent substrate, they both retain their biologic activity; the change in enzyme activity as a result of the enzyme-antibody-antigen reaction is proportional to the concentration of the antigen and can be measured spectrophotometrically or with the naked eye. Many variations of the method have been developed.

A genetic rearrangement through loss of segments of DNA or RNA, bringing sequences which are normally separated into close proximity. This deletion may be detected using cytogenetic techniques and can also be inferred from the phenotype, indicating a deletion at one specific locus.

DNA sequences which are recognized (directly or indirectly) and bound by a DNA-dependent RNA polymerase during the initiation of transcription. Highly conserved sequences within the promoter include the Pribnow box in bacteria and the TATA BOX in eukaryotes.

The sum of the weight of all the atoms in a molecule.

The type species of BETARETROVIRUS commonly latent in mice. It causes mammary adenocarcinoma in a genetically susceptible strain of mice when the appropriate hormonal influences operate.

An enzyme that catalyzes the hydrolysis of alpha-2,3, alpha-2,6-, and alpha-2,8-glycosidic linkages (at a decreasing rate, respectively) of terminal sialic residues in oligosaccharides, glycoproteins, glycolipids, colominic acid, and synthetic substrate. (From Enzyme Nomenclature, 1992)

The quantity of measurable virus in a body fluid. Change in viral load, measured in plasma, is sometimes used as a SURROGATE MARKER in disease progression.

Recombinases that insert exogenous DNA into the host genome. Examples include proteins encoded by the POL GENE of RETROVIRIDAE and also by temperate BACTERIOPHAGES, the best known being BACTERIOPHAGE LAMBDA.

INFLAMMATION of the LIVER in humans caused by HEPATITIS C VIRUS, a single-stranded RNA virus. Its incubation period is 30-90 days. Hepatitis C is transmitted primarily by contaminated blood parenterally, and is often associated with transfusion and intravenous drug abuse. However, in a significant number of cases, the source of hepatitis C infection is unknown.

A group of enzymes that catalyzes the hydrolysis of terminal, non-reducing beta-D-galactose residues in beta-galactosides. Deficiency of beta-Galactosidase A1 may cause GANGLIOSIDOSIS, GM1.

Viruses whose hosts are in the domain ARCHAEA.

New defective RNAs from citrus tristeza virus: evidence for a replicase-driven template switching mechanism in their generation. (1/552)

Defective RNAs (D-RNAs) ranging in size from 1968 to 2759 nt were detected in four citrus tristeza virus (CTV) isolates by hybridization of electroblotted dsRNAs with two probes specific for the 5'- and 3'-terminal genomic regions. The RNAs that hybridized with both probes were eluted, cloned and sequenced. Comparison with the sequences of the corresponding genomic regions of the helper virus showed, in all cases, over 99% nucleotide identity and direct repeats of 4-5 nt flanking or in the vicinity of the junction sites. The presence of the repeats from two separate genome locations suggests a replicase-driven template switching mechanism for the generation of these CTV D-RNAs. Two of the CTV isolates that differed greatly in their pathogenicity contained an identical D-RNA, suggesting that it is unlikely that this D-RNA is involved in symptom modulation, which may be caused by another factor. (+info)

Virus promoters determine interference by defective RNAs: selective amplification of mini-RNA vectors and rescue from cDNA by a 3' copy-back ambisense rabies virus. (2/552)

Typical defective interfering (DI) RNAs are more successful in the competition for viral polymerase than the parental (helper) virus, which is mostly due to an altered DI promoter composition. Rabies virus (RV) internal deletion RNAs which possess the authentic RV terminal promoters, and which therefore are transcriptionally active and can be used as vectors for foreign gene expression, are poorly propagated in RV-infected cells and do not interfere with RV replication. To allow DI-like amplification and high-level gene expression from such mini-RNA vectors, we have used an engineered 3' copy-back (ambisense) helper RV in which the strong replication promoter of the antigenome was replaced with the 50-fold-weaker genome promoter. In cells coinfected with ambisense helper virus and mini-RNAs encoding chloramphenicol acetyltransferase (CAT) and luciferase, mini-RNAs were amplified to high levels. This was correlated with interference with helper virus replication, finally resulting in a clear predominance of mini-RNAs over helper virus. However, efficient successive passaging of mini-RNAs and high-level reporter gene activity could be achieved without adding exogenous helper virus, revealing a rather moderate degree of interference not precluding substantial HV propagation. Compared to infections with recombinant RV vectors expressing CAT, the availability of abundant mini-RNA templates led to increased levels of CAT mRNA such that CAT activities were augmented up to 250-fold, while virus gene transcription was kept to a minimum. We have also exploited the finding that internal deletion model RNAs behave like DI RNAs and are selectively amplified in the presence of ambisense helper virus to demonstrate for the first time RV-supported rescue of cDNA after transfection of mini-RNA cDNAs in ambisense RV-infected cells expressing T7 RNA polymerase. (+info)

Multiple mitochondrial viruses in an isolate of the Dutch Elm disease fungus Ophiostoma novo-ulmi. (3/552)

The nucleotide sequences of three mitochondrial virus double-stranded (ds) RNAs, RNA-4 (2599 nucleotides), RNA-5 (2474 nucleotides), and RNA-6 (2343 nucleotides), in a diseased isolate Log1/3-8d2 (Ld) of the Dutch elm disease fungus Ophiostoma novo-ulmi have been determined. All these RNAs are A-U-rich (71-73% A + U residues). Using the fungal mitochondrial genetic code in which UGA codes for tryptophan, the positive-strand of each of RNAs 4, 5, and 6 contains a single open reading frame (ORF) with the potential to encode a protein of 783, 729, and 695 amino acids, respectively, all of which contain conserved motifs characteristic of RNA-dependent RNA polymerases (RdRps). Sequence comparisons showed that these RNAs are related to each other and to a previously characterized RNA, RNA-3a, from the same O. novo-ulmi isolate, especially within the RdRp-like motifs. However, the overall RNA nucleotide and RdRp amino acid sequence identities were relatively low (43-55% and 20-32%, respectively). The 5'- and 3'-terminal sequences of these RNAs are different, but they can all be folded into potentially stable stem-loop structures. Those of RNA-4 and RNA-6 have inverted complementarity, potentially forming panhandle structures. Their molecular and biological properties indicate that RNAs 3a, 4, 5, and 6 are the genomes of four different viruses, which replicate independently in the same cell. These four viruses are also related to a mitochondrial RNA virus from another fungus, Cryphonectria parasitica, recently designated the type species of the Mitovirus genus of the Narnaviridae family, and to a virus from the fungus Rhizoctonia solani. It is proposed that the four O. novo-ulmi mitochondrial viruses are assigned to the Mitovirus genus and designated O. novo-ulmi mitovirus (OnuMV) 3a-Ld, 4-Ld, 5-Ld, and 6-Ld, respectively. Northern blot analysis indicated that O. novo-ulmi Ld nucleic acid extracts contain more single-stranded (ss, positive-stranded) RNA than dsRNA for all three newly described mitoviruses. O. novo-ulmi RNA-7, previously believed to be a satellite-like RNA, is shown to be a defective RNA, derived from OnuMV4-Ld RNA by multiple internal deletions. OnuMV4-Ld is therefore the helper virus for the replication of both RNA-7 and another defective RNA, RNA-10. Sequence comparisons indicate that RNA-10 could be derived from RNA-7, as previously suggested, or derived directly from RNA-4. (+info)

Frequency and stability of chromosomal integration of adenovirus vectors. (4/552)

One of the limitations of adenovirus vectors is the lack of machinery necessary for their integration into host chromosomes, resulting in short-term gene expression in dividing cells. We analyzed frequencies of integration and persistence of gene expression from integrated adenovirus vectors. Both E1-substituted and helper-dependent adenovirus vectors achieved similar integration efficiencies of approximately 10(-3) to 10(-5) per cell, with the helper-dependent vector showing slightly higher efficiencies. In stable cell pools, gene expression of the integrated vector persisted for at least 50 cell divisions without selection. However, some stable cell clones showed changes in gene expression, which were accompanied by structural changes in the integrated vector DNA. (+info)

Tamplicon-7, a novel T-lymphotropic vector derived from human herpesvirus 7. (5/552)

We describe the derivation of a novel T-cell-defective virus vector employing the human herpesvirus 7 (HHV-7). The new vector, designated Tamplicon-7, replicates in CD4(+) T cells. The system is composed of a helper virus and defective virus genomes derived by the replication of the input Tamplicon vector. There are two cis-acting functions required for the replication and packaging of the defective virus genomes in the presence of the helper virus: the viral DNA replication origin and the composite cleavage and packaging signal, which directs the cleavage and packaging of defective virus genomes. Viral DNA replication is compatible with the rolling circle mechanism, producing large head-to-tail concatemers of the Tamplicon vector. Thus, in the presence of the helper virus, the replicated vectors are packaged and secreted into the medium. Furthermore, we have shown that the vector can be employed to express a foreign gene, encoding the green fluorescent protein, in the T cells infected with the HHV-7 helper virus. We predict that the Tamplicon-7 vector might be potentially useful for gene therapy of diseases affecting the human CD4(+) T cells, including autoimmune diseases, T-cell lymphomas, and AIDS. (+info)

Interactions between tombusviruses and satellite RNAs of tomato bushy stunt virus: a defect in sat RNA B1 replication maps to ORF1 of a helper virus. (6/552)

The biological properties of two recently described satellite RNAs of tomato bushy stunt virus (TBSV) were analyzed in natural and experimental hosts. Full-length cDNA clones were constructed for sat RNAs B1(822 nt) and B10 (612 nt) and used in inoculations with satellite-free transcripts of different tombusviruses. In all virus-host combinations tested, TBSV sat RNA B10 drastically reduced the accumulation of viral genomic RNA and attenuated symptoms. In contrast, sat RNA B1 caused a less marked reduction of viral RNA level and did not have any effect on symptoms. Experiments with Nicotiana benthamiana protoplasts showed that the differential effects of sat RNAs B1 and B10 on TBSV titer were related to differential abilities to interfere with virus replication. Three tombusviruses tested were able to maintain both sat RNAs in N. benthamiana plants, although carnation Italian ringspot virus (CIRV) was a poor helper for sat RNA B1. Using chimeric viruses, a strong determinant for low sat RNA B1 accumulation was mapped to the 5'-terminal part of the genome of CIRV. The poor helper activity of CIRV was shown to be due to low sat RNA B1 replication. A single-nucleotide mutation in the start codon of CIRV ORF1 restored the ability to replicate sat RNA B1 to high levels. This mutant encodes an ORF1 that is 22 amino acids shorter at the N-terminus than the wild-type virus. (+info)

Use of helper-dependent adenoviral vectors of alternative serotypes permits repeat vector administration. (7/552)

We have developed a new helper adenovirus (Ad) based on serotype 2, Ad2LC8cCARP, for use in the Cre/loxP system (Parks et al. Proc Natl Acad Sci USA, 1996; 93: 13565-13570) to generate Ad vectors deleted of all protein coding sequences (helper-dependent Ad vectors (hdAd)). A comparison of Ad2LC8cCARP and our original helper virus (based on serotype 5, Ad5LC8cluc) showed that the two helper viruses amplified hdAd with a similar efficiency, and resulted in a similar yield and purity after large-scale preparation of vector. In vitro, the resulting hdAd2 had a similar transduction efficiency and expression kinetics of transgene (beta-gal) as the hdAd5. An important feature of the helper-dependent system is that all virion components, except the virion DNA, derive from the helper virus. Consequently, vectors produced with help from Ad2LC8cCARP were not neutralized by antibodies against Ad5, and vectors produced with Ad5 helper were resistant to neutralizing antibodies against Ad2. Analysis of transgene expression in mouse liver after intravenous injection of the Ad2-based hdAd showed that the vector could efficiently transduce the liver, and produce high levels of a foreign transgene, similar to those expressed by the hdAd generated with the Ad5 helper virus. Mice immunized with hdAd2 produced Ad2-neutralizing antibodies, which did not cross-react with hdAd5. To determine if successful repeat Ad vector administration could be achieved by sequential use of alternative Ad serotypes, we injected mice with hdAd2 (hSEAP) followed 3 months later by a lacZ-expressing hdAd of either the same or different serotype. Repeated administration of hdAd2 resulted in a 30- to 100-fold reduction in transgene expression compared with naive animals. In contrast, no decrease in transgene expression was observed when the second vector was of a different serotype. These results demonstrate that effective vector readministration can be achieved by the sequential use of hdAds based on alternative serotypes. (+info)

Delivery of herpes simplex virus amplicon-based vectors to the dentate gyrus does not alter hippocampal synaptic transmission in vivo. (8/552)

Herpes simplex virus type-1 (HSV) amplicon vectors containing neuroprotective genes can alter cell physiology and enhance survival following various insults. However, to date, little is known about effects of viral infection itself (independent of the gene delivered) on neuronal physiology. Electrically-evoked synaptic responses are routinely recorded to measure functional alterations in the nervous system and were used here to assess the potential capability of HSV vectors to disrupt physiology of the hippocampus (a forebrain structure involved in learning that is highly susceptible to necrotic insult, making it a frequent target in gene therapy research). Population excitatory post-synaptic potentials (EPSPs) were recorded in the dentate gyrus (DG) and in area CA3 in vivo 72 h after infusion of an HSV vector expressing a reporter gene (lacZ) or vehicle into the DG. Evoked perforant path (PP-DG) or mossy fiber (MF-CA3) EPSPs slope values measured across input/output (I/O) curves were not altered by infection. Paired-pulse facilitation at either recording site was also unaffected. X-gal-positive granule cells surrounded the recording electrode (PP-DG recording) and stimulating electrode tracts (MF-CA3 recording) in animals that received vector, suggesting that we had measured function, at least in part, in infected neurons. Because of the negative electrophysiological result, we sought to deliver a gene with an HSV amplicon which would affect the measured endpoints, as a positive control. Delivery of calbindin D28kpotentiated PP-DG synaptic strength, indicating that our recording system could detect alterations due to vector expression. Thus, the data indicate that HSV vectors are benign, in regard to effects on synaptic function, and support the use of these vectors as a safe method to deliver selected genes to the central nervous system. (+info)

A helper virus is a virus that allows an otherwise-deficient coinfecting virus to replicate. These can be naturally occurring ... Helper viruses are also commonly used to replicate and spread viral vectors for gene expression and gene therapy. Helper ... v t e (Virology, All stub articles, Virus stubs). ... as with Hepatitis D virus, which requires Hepatitis B virus to ... dependent virus Virophage Graham BS, Crowe JE, Ledgerwood JE (2007). "14 - Immunization Against Viral Diseases". In Knipe DM, ...

https://en.wikipedia.org/wiki/Helper_virus

A helper dependent virus, also termed a gutless virus, is a synthetic viral vector dependent on the assistance of a helper ... Helper dependent viruses can also occur in nature without being "gutted". The term satellite virus has been given to a large ... Hepatitis D virus (HDV) is an example of a replication defective, helper dependent ssRNA virus because it requires Hepatitis B ... Naturally-occurring satellite viruses are also helper virus dependent, and can sometimes be modified to become viral vectors. ...

https://en.wikipedia.org/wiki/Helper_dependent_virus

... they are not always found within their helper viruses. Satellite viruses Single-stranded RNA satellite viruses (unnamed family ... and foot-and-mouth virus), SARS virus, hepatitis C virus, yellow fever virus, and rubella virus. Group V: viruses possess ... Viruses that cause chickenpox and herpes are found here. Group II: viruses possess single-stranded DNA. All viruses that have ... which is normally the parental virus. They can also interfere with the helper virus. Defective interfering particles (RNA) ...

https://en.wikipedia.org/wiki/Virus_classification

... a group of small DNA viruses that infect protists and require a helper virus to replicate; they are a type of satellite virus. ... Zamilon is restricted in its range of helper viruses; it can be supported by viruses from Mimivirus-like Mimiviridae lineages B ... Although the helper virus formed a high proportion of abnormal virions in the presence of Zamilon, these were also observed at ... Zamilon does not appear to inhibit the ability of its helper virus to replicate significantly, nor to lyse its host amoebae ...

https://en.wikipedia.org/wiki/Zamilon_virophage

... "helper" virus. TBSV infections often produce significant numbers of DIs from consistent parts of the genome under experimental ... Tomato bushy stunt virus (TBSV) is a virus of the tombusvirus family. It was first reported in tomatoes in 1935 and primarily ... Yamamura, Y; Scholthof, HB (1 September 2005). "Tomato bushy stunt virus: a resilient model system to study virus-plant ... Martelli, G.P.; Russo, M.; Rubino, L. (December 2001). "Tomato bushy stunt virus". Descriptions of Plant Viruses. Association ...

https://en.wikipedia.org/wiki/Tomato_bushy_stunt_virus

THαβ helper cells provide the host immunity against viruses. Their differentiation is triggered by IFN α/β or IL-10. Their key ... Th17 helper cells are a subset of T helper cells developmentally distinct from Th1 and Th2 lineages producing interleukin 17 ( ... The novel characterisation of another T helper subtype, T helper 17 cells (Th17) has cast further doubt on the basic Th1/Th2 ... also known as Type 1 and Type 2 helper T cells, respectively). Th1 helper cells lead to an increased cell-mediated response ( ...

https://en.wikipedia.org/wiki/T_helper_cell

The helper virus identifies and responds to signals within the IBV D-RNA that are responsible for replication and packaging of ... With the helper virus dependent system, chIFN-gamma-containing IBV D-RNA was successfully used to induce the expression of ... One particularly promising method of IBV D-RNA-mediated heterologous gene expression uses the helper virus dependent system to ... virus internal ribosome entry site sequence in avian infectious bronchitis virus defective RNAs abolishes rescue by helper ...

https://en.wikipedia.org/wiki/Infectious_bronchitis_virus_D-RNA

They are only limited by the virus they must infect with, also known as the helper virus. These helper viruses are necessary ... A common helper virus in humans is the adenovirus.[citation needed] Dependoparvovirus is not infectious enough to trigger an ... viruses because they cannot replicate productively in their host cell without the cell being coinfected by a helper virus such ... Dependoparvovirus (formerly Dependovirus or Adeno-associated virus group) is a genus in the subfamily Parvovirinae of the virus ...

https://en.wikipedia.org/wiki/Dependoparvovirus

... spreads by co-infecting a cell with a helper virus. The first helper virus that was described as ... When the helper virus kills the host cell, the new AAV virions are released. If there is not a helper virus present, AAV ... If there is a helper virus, AAV's gene expression activates, allowing the virus to replicate using the host cell's polymerase. ... "Adeno-associated virus vectors can be efficiently produced without helper virus". Gene Therapy. 5 (7): 938-45. doi:10.1038/sj. ...

https://en.wikipedia.org/wiki/Adeno-associated_virus

Plant satellite RNAs and virusoids depend on their respective helper viruses for replication, while the helper viruses ... Virusoids, while being studied in virology, are subviral particles rather than viruses. Since they depend on helper viruses, ... and supported by a helper virus (Hepatitis B virus) to form virions; however, the virions possess a much larger genome size (~ ... Virusoids are essentially viroids that have been encapsulated by a helper virus coat protein. They are thus similar to viroids ...

https://en.wikipedia.org/wiki/Virusoid

The virus activates a subset of T-helper cells called Th1 cells. The result is a proliferation of Th1 cells and overproduction ... Human T-cell lymphotropic virus type 1 or human T-lymphotropic virus (HTLV-I), also called the adult T-cell lymphoma virus type ... Few, if any, free virions are produced and there is usually no detectable virus in the blood plasma though the virus is present ... In Americas the virus is found in indigenous populations and descendants of African ancestry from where it is thought to have ...

https://en.wikipedia.org/wiki/Human_T-lymphotropic_virus_1

Virophages are viruses that replicate only when host cells are co-infected with helper viruses. Following co-infection, helper ... The replication of virophages can negatively impact the replication of helper viruses. Sputnik and mavirus are examples of ... Prophages are genomes of bacteriophages (a type of virus) that are inserted into bacterial chromosomes; prophages can then be ... Miller DW, Miller LK (October 1982). "A virus mutant with an insertion of a copia-like transposable element". Nature. 299 (5883 ...

https://en.wikipedia.org/wiki/Mobilome

"Role of T-Helper 9 Cells in Chronic Hepatitis C-Infected Patients". Viruses. 10 (7): 341. doi:10.3390/v10070341. PMC 6071239. ... In cell biology, TH9 cells (T helper type 9 cells, CD4+IL-9+IL-13−IFNγ − ) are a sub-population of CD4+T cells that produce ... Kaplan, Mark H.; Hufford, Matthew M.; Olson, Matthew R. (May 2015). "The development and in vivo function of T helper 9 cells ... GATA-3 in TH9 cells development represses transcriptional factor FOXP3, which would other wise let to other T helper cell ...

https://en.wikipedia.org/wiki/Th_9_cell

Having this would possibly reduce the need for a replication-competent helper virus. Other advantages are human to human ... Foamy virus in humans occurs only as a result of zoonotic infection. The first description of foamy virus (FV) was in 1954. It ... Liu W, Liu Z, Cao X, Cao Z, Xue L, Zhu F, He X, Li W (2007). "Recombinant human foamy virus, a novel vector for neurological ... Human foamy virus (HFV) is a retrovirus and specifically belongs to the genus Spumavirus. The spumaviruses are complex and ...

https://en.wikipedia.org/wiki/Human_foamy_virus

Rather, they associate with a second viral-encoded accessory protein, termed "helper component" (HC). The virion and the HC ... "Carrot virus Y". www.agric.wa.gov.au. Retrieved 2019-12-13. "Carrot virus Y: Page 2 of 2". www.agric.wa.gov.au. Archived from ... Carrot virus Y (CarVY) is a (+)ss-RNA virus that affects crops of the carrot family (Apiaceae), such as carrots, anise, chervil ... This is a result of the virus using the plant as a host, as the plant's energy is diverted to the virus rather than to the ...

https://en.wikipedia.org/wiki/Carrot_virus_Y

... are completely dependent on a helper virus for replication. The symbiotic relationship between a satellite and a helper virus ... The tobacco necrosis virus was the virus that led to the discovery of the first satellite virus in 1962. Scientists discovered ... virus satellite RNA Tomato black ring virus satellite RNA Beet ringspot virus satellite RNA Beet necrotic yellow vein virus ... mosaic virus small satellite RNA Peanut stunt virus satellite RNA Turnip crinkle virus satellite RNA Tomato bushy stunt virus ...

https://en.wikipedia.org/wiki/Satellite_(biology)

Helper T-cells require a much milder activation stimulus than cytotoxic T cells. Helper T cells can provide extra signals that ... "The Viruses That Make Us: A Role For Endogenous Retrovirus In The Evolution Of Placental Species". University of California, ... Follicular helper T (Tfh) cells are another distinct population of effector CD4+ T cells that develop from naive T cells post- ... It has several different pathways that all end with the virus being unable to replicate. One of the pathways is siRNA in which ...

https://en.wikipedia.org/wiki/Adaptive_immune_system

They called it "Hepatitis Delta Virus" (HDV). This new virus was found to be defective. HDV needed HBV to act as a helper ... Agents of this virus resemble that of plant viroids. It is still hard to tell how many stereotypes exist because HDV is under ... Flu viruses can be directly transmitted (via droplets from sneezing or coughing) from pigs to people, and vice versa. These ... Human Immunodeficiency virus (HIV) can cause AIDS which is an acronym for Acquired Immunodeficiency Syndrome (AIDS), a ...

https://en.wikipedia.org/wiki/Sociology_of_health_and_illness

It is a satellite virus, requiring P2-related helper phage to grow lytically. The P4 virion has a tail and an icosahedral head ... It is a satellite virus which cannot engage in lytic growth without the presence of a P2-related helper phage. It generally ... Enterobacteria phage P4 (also known as satellite phage P4) is a temperate bacteriophage strain of species Escherichia virus P2 ... Christie, GE; Calendar, R (1990). "Interactions between satellite bacteriophage P4 and its helpers". Annual Review of Genetics ...

https://en.wikipedia.org/wiki/Enterobacteria_phage_P4

October 2002). "Subcellular Location of the Helper Component-Proteinase of Cowpea Aphid-Borne Mosaic Virus". Virus Genes. 25 (2 ... Her main area of research has been viruses which attack the cowpea, one of the major food crops of Zimbabwe. Idah Sithole was ... Returning to Zimbabwe, she became a Lecturer at the University of Zimbabwe in 1992 on viruses which infect plants. Her chief ... When she was awarded a USAID Fellowship in 1983, Sithole chose to continue her education, studying plant and virus genetics. ...

https://en.wikipedia.org/wiki/Idah_Sithole-Niang

MANZER FE; MERRIAM, DC; HELPER, PR. 1978. Effects of Potato virus S and two strains of Potato virus X on yield of Russet ... Description of plant viruses: Potato virus S. Surrey, England: Commonw. Mycol. Inst. /Assoc.Appl.Biol.,Kew. 60p. WRIGHT, N.S. ... Combined effects Potato viruses X and S on yield of Netted Gem and White Rose potatoes. American Potato Journal. 47:475-478. ( ... Potato virus S. In: STEVENSON, W.R. et al. (Ed.). Compendium of potato diseases. 2.ed. St Paul,. 67p. ...

https://en.wikipedia.org/wiki/PVS_(project)

"Chimeric retroviral helper virus and picornavirus IRES sequence to eliminate DNA methylation for improved retroviral packaging ... As an example, SPA targeting to the host factor LSF, which represses expression of the human immunodeficiency virus (HIV) type ... "Targeted derepression of the human immunodeficiency virus type 1 long terminal repeat by pyrrole-imidazole polyamides". J. ...

https://en.wikipedia.org/wiki/Therapeutic_gene_modulation

The capsid protein of satellite panicum mosaic virus contributes to systemic invasion and interacts with its helper virus. ... PMV is serologically related to Molina streak virus and Maize mild mottle virus. There exists a satellite virus to panicum ... Viruses and virus diseases of Poaceae (Gramineae). Inra. p. 798. ISBN 2-7380-1088-1. ICTVdB - The Universal Virus Database, ... The virus can live up to nine years in infected plant debris. The virus is moved around the environment by wind, rain, and ...

https://en.wikipedia.org/wiki/Panicum_mosaic_virus

Key features of replication include no helper virus required and no proteins are encoded for. Unlike the other family of ... "ICTV Virus Taxonomy Profile: Avsunviroidae". The Journal of General Virology. 99 (5): 611-612. doi:10.1099/jgv.0.001045. PMID ... retrieved 2007-03-16 Description of Plant Viruses- Avsunviroidae, archived from the original on 2007-02-13, retrieved 2007-03- ...

https://en.wikipedia.org/wiki/Avsunviroidae

His lab has done major work on the regulation and proliferation of follicular helper T cells, as well as immunological ... Crotty S, Cameron CE, Andino R (2001). "RNA virus error catastrophe: Direct molecular test by using ribavirin". Proceedings of ... the virus that causes COVID-19, and later confirmed that the adaptive immune response is lasting. In 2020, Crotty joined the ... Crotty has warned that this T-cell immunity does not equal protection against the virus. Choi YS, Kageyama R, Eto D, Escobar TC ...

https://en.wikipedia.org/wiki/Shane_Crotty

Viruses like Sputnik that depend on co-infection of the host cell by helper viruses are known as satellite viruses. At its ... Sputnik uses the helper virus's machinery for reproduction and inhibits replication of the helper virus. It is known as a ... was the first known satellite virus that inhibited replication of its helper virus and thus acted as a parasite of that virus. ... is a subviral agent that reproduces in amoeba cells that are already infected by a certain helper virus; ...

https://en.wikipedia.org/wiki/Sputnik_virophage

Virus tropism Virus factors Host factors Virus tropism refers to the virus' preferential site of replication in discrete cell ... The primary cause of immunosuppression in HIV patients is due to the depletion of CD4+ T helper cells. Interestingly, ... varicella zoster virus), smallpox (variola), HIV (human immunodeficiency virus). A minority of viruses can disseminate via the ... For a virus to successfully infect and cause disease in the host, it has to encode specific virus factors in its genome to ...

https://en.wikipedia.org/wiki/Viral_pathogenesis

For its reproduction the virus needs a helper or associated virus which is called Simian sarcoma associated virus (SSAV). HL23V ... Woolly monkey sarcoma virus (WMSV), with synonym Simian sarcoma virus (often abbreviated by SSV, but this may also stand for ... specific regions of the simian sarcoma-associated virus genome are found in defective viruses and in the simian sarcoma virus, ... Virus-specific phosphoproteins in simian sarcoma virus-transformed primate cells, in: EMBO J. 1982; 1(9): 1029-1033 PMC 553157 ...

https://en.wikipedia.org/wiki/Woolly_monkey_sarcoma_virus

"Pathogenetic effector function of CD4-positive T helper 1 cells in hepatitis B virus transgenic mice". Journal of Immunology. ... They altered the DNA of cowpox virus by inserting a gene from other viruses (namely Herpes simplex virus, hepatitis B and ... The Sindbis virus and Semliki Forest virus have been used to build recombinant alphavirus replicons. Unlike conventional DNA ... activity of vaccinia virus recombinants expressing the hepatitis B virus surface antigen and the herpes simplex virus ...

https://en.wikipedia.org/wiki/DNA_vaccine

... fibroblasts by cloned Abelson murine leukemia virus DNA and recovery of transmissible virus by recombination with helper virus ... In Weinberg's lab, Tabin constructed murine leukemia virus, the first recombinant retrovirus that could be used as a eukaryotic ... "Human EJ bladder carcinoma oncogene is homologue of Harvey sarcoma virus ras gene". Nature. 297 (5866): 474-8. Bibcode: ...

https://en.wikipedia.org/wiki/Clifford_Tabin

... thin viruses that infect bacteria) by fusing the virus's capsid protein to one peptide out of a collection of peptide sequences ... Those that remain can be eluted, used to produce more phage (by bacterial infection with helper phage) and to produce a phage ... Loss of phage infectivity can be avoided by using a phagemid plasmid and a helper phage so that the resultant phage contains ... However, this led to the incorporation of more helper phage genomes rather than phagemid genomes. In all cases, phage display ...

https://en.wikipedia.org/wiki/Phage_display

The 32-year-old pivot, twice the NHL's leading playoff scoring, picked up helpers on all three goals, with each play prettier ... it was confirmed that Krejčí had been diagnosed with the H1N1 virus, which sidelined him for a period of time. On 5 May 2010, ...

https://en.wikipedia.org/wiki/David_Krejčí

Viruses that inhibit IFN signaling include Japanese Encephalitis Virus (JEV), dengue type 2 virus (DEN-2), and viruses of the ... Type II interferons are also released by cytotoxic T cells and type-1 T helper cells. However, they block the proliferation of ... Some viruses escape the anti-viral activities of interferons by gene (and thus protein) mutation. The H5N1 influenza virus, ... Some viruses can encode proteins that bind to double-stranded RNA (dsRNA) to prevent the activity of RNA-dependent protein ...

https://en.wikipedia.org/wiki/Interferon

COVID-19 in the dormitories saw a more rapid spread of the virus compared to the rest of the population in Singapore. According ... Also, a sizable number of women work overseas as domestic helpers and caregivers. The Philippine Overseas Employment ... domestic helpers, factory workers and other manual jobs. Most of them come from Southeast Asia. A 2020 Greenpeace investigation ...

https://en.wikipedia.org/wiki/Migrant_worker

Portals: Medicine Viruses COVID-19 (Wikipedia articles in need of updating from December 2021, All Wikipedia articles in need ... Unmodified mRNA inhibits immunogenicity by triggering the production of interferons that block the generation of T helper cells ... "mRNA based SARS-CoV-2 vaccine candidate CVnCoV induces high levels of virus neutralizing antibodies and mediates protection in ...

https://en.wikipedia.org/wiki/CureVac_COVID-19_vaccine

Inhibition of follicular T helper cells by CD8+ Treg is essential for self tolerance. Nature 2010;467:328 Kim, H-J, Wang X, ... Zhao ZS, Granucci F, Yeh L, Schaffer PA, Cantor H. Molecular mimicry by herpes simplex virus-1: Autoimmune disease after viral ...

https://en.wikipedia.org/wiki/Harvey_Cantor

Type 1 diabetes has a risk associated with coxsackie 4B virus, there is a potential for involvement of class I loci, ... The association with class I would be unusual since T-helper mediated autoantibody production is characteristic of disease, ...

https://en.wikipedia.org/wiki/HLA_A1-B8-DR3-DQ2

Upregulation of intercellular adhesion molecule-1 (ICAM-1) and cytokines associated with T-helper 1 immune response, may also ... Hepatitis C virus-associated diseases, Lichenoid eruptions, Oral mucosal pathology). ... T cells on keratinocytes or by encounters with activated CD4+ helper T cells or cytokines produced by activated CD4+ helper T ...

https://en.wikipedia.org/wiki/Lichen_planus

... that pregnant women and certain populations such as native North Americans have a greater likelihood of developing a T helper ... The G4 virus, also known as the "G4 swine flu virus" (G4) and "G4 EA H1N1", is a swine influenza virus strain discovered in ... "The swine flu virus is not a new virus and does not very spread and is pathogenic to humans and animals [translated from ... The virus is a variant genotype 4 (G4) Eurasian avian-like (EA) H1N1 virus that mainly affects pigs, but there is some evidence ...

https://en.wikipedia.org/wiki/Influenza_A_virus_subtype_H1N1

CD4 cells or helper T cells provide protection against different pathogens. Naive T cells, which are immature T cells that have ... It is most effective in removing virus-infected cells, but also participates in defending against fungi, protozoans, cancers, ... CD4+ T-helper cells may be differentiated into two main categories: TH1 cells which produce interferon gamma and lymphotoxin ... Common innate lymphoid progenitors may then be differentiated into a natural killer progenitor (NKp) or a common helper like ...

https://en.wikipedia.org/wiki/Cell-mediated_immunity

... helper T cell - hemopexin - hemoglobin - herpes simplex virus protein vmw65 - heterocyclic compound - heterotroph - ... RNA virus - RNA-binding protein - RNA-directed DNA polymerase - rod outer segment - rough ER sarcoplasmic reticulum - satellite ... DNA virus - DNA-binding protein - dopamine D1 receptor - dopamine D2 receptor - dopamine receptor - double helix - Drosophila ... virus (biology) - vitamin - vitamin D-dependent calcium-binding protein - vitellogenin - vitronectin - von Willebrand factor ...

https://en.wikipedia.org/wiki/Index_of_biochemistry_articles

... can be envisaged as the result of the continuous challenge of the unavoidable exposure to a variety of antigens such as viruses ... ratio the accumulation and clonal expansion of memory and effector T cells impaired development of CD4+ T follicular helper ...

https://en.wikipedia.org/wiki/Immunosenescence

... can be associated with exposure to Epstein-Barr virus (EBV) or human T-cell leukaemia virus 1 (HTLV-1). ... It originates from follicular T helper (TFH) cells, which is important in maintaining immune response. Autoimmune disorders ... Matsuoka, Masao (August 2003). "Human T-cell leukemia virus type I and adult T-cell leukemia". Oncogene. 22 (33): 5131-5140. ... Rezk, Sherif A.; Zhao, Xiaohui; Weiss, Lawrence M. (September 2018). "Epstein-Barr virus (EBV)-associated lymphoid ...

https://en.wikipedia.org/wiki/Mature_T-cell_lymphoma

Once the virus has entered the blood stream, it attaches to and enters t-helper cells (CD4 cells) in order to replicate. After ... Human Immunodeficiency Virus (HIV) and Hepatitis C Virus (HCV) co-infection is a multi-faceted, chronic condition that ... Other tests can detect the presence of the HIV virus by calculating the amount of actual virus present in the blood. None of ... The virus RNA can be detected in the blood 1-2 weeks after exposure. For a quantitative test, a low viral load is any value ...

https://en.wikipedia.org/wiki/Hepatitis_C_and_HIV_coinfection

... the virus can be transferred to helper CD4+ T-cells, contributing to the developing infection. This infection of dendritic ... Many other viruses, such as the SARS virus, seem to use DC-SIGN to 'hitchhike' to its target cells. However, most work with ... "Difference in production of infectious wild-type measles and vaccine viruses in monocyte-derived dendritic cells". Virus Res. ... Here they act as antigen-presenting cells: they activate helper T-cells and killer T-cells as well as B-cells by presenting ...

https://en.wikipedia.org/wiki/Dendritic_cell

Type 1 helper T cell (Th1) response of 84 randomly selected participants (28 for each vaccine group and 14 for placebo group) ... Scholia has a profile for Nanocovax (Q106518336). Portals: Medicine Viruses COVID-19 (CS1 Vietnamese-language sources (vi), CS1 ... Type 1 and type 2 helper T cell (Th1/Th2) response on 77 randomly selected participants (66 in vaccine group and 11 in placebo ... Surrogate virus neutralization test (sVNT) results were reported as mean inhibition rate (%). Up to day 28 (before 2nd ...

https://en.wikipedia.org/wiki/Nanocovax

... yet no gene for the toxin has been found on the genome of the virus. The virus manipulates the infected cell to express its own ... focused on the action of Th1 T-helper cells. Some of the major products are IL-1, IL-2, IL-6, TNF-α, gamma interferon (IFN-γ), ... These toxins are encoded by SAg genes that were incorporated into the mouse genome from the mouse mammary tumour virus (MMTV). ... The result is that these mice are immune to infection by the virus later in life. Similar endogenous SAg-dependent selection ...

https://en.wikipedia.org/wiki/Superantigen

... further contained a RNA virus known as Leptomonas seymouri narna-like virus 1 (Lepsey NLV1). So, it appears that a great ... A variety of regulatory T and B cells have been implicated in VL, including Type 1 T helper cells that secrete IL-10 in ... IL-12 is important in the development and maintenance of Type 1 T helper cell responses and protective immunity so its role in ... Sukla, Soumi; Roy, Syamal; Sundar, Shyam; Biswas, Subhajit (2017). "Leptomonas seymouri narna-like virus 1 and not ...

https://en.wikipedia.org/wiki/Visceral_leishmaniasis

... as the T regulatory cell transferred to the patient may change into T helper 17 (Th17) cells, which are pro-inflammatory rather ... CD4+ cells are leukocytes responsible for protecting animals from foreign invaders such as bacteria and viruses. Defects in ...

https://en.wikipedia.org/wiki/FOXP3

2016). "Protective monotherapy against lethal Ebola virus infection by a potently neutralizing antibody". Science. 351 (6279): ... process and present antigen to T helper cells (). This study uncovered a critical step in the process of T-B cell cooperation ... Neutralizing anti-influenza virus antibodies and uses thereof (WO2010010467) Methods for producing antibodies from plasma cells ... Among these is FI6 that neutralizes all influenza A viruses (), MPE8 that neutralizes four different paramyxoviruses () and ...

https://en.wikipedia.org/wiki/Antonio_Lanzavecchia

Many viruses (HIV being the most extreme example) seem to exploit the immune system's use of tolerance induction to evade the ... Kleaiter N, Hermann; Baier, Gottfried (2010). "NFAT pulls the strings during CD4+ T helper cell effector functions". Blood. 115 ... circulating cells called lymphocytes form a primary army that defends the body against pathogenic viruses, bacteria and ...

https://en.wikipedia.org/wiki/Clonal_anergy

Up to 40,000 individuals were caught and exported for research into those diseases, as well as Epstein-Barr virus, for the ... where helpers take on more of the work. Total care for infants remains constant with varying group size, and infant outcome is ...

https://en.wikipedia.org/wiki/Cotton-top_tamarin

Iwata R, Sasaki N, Agui T (2010). "Contiguous gene deletion of Ptprk and Themis causes T-helper immunodeficiency (thid) in the ... by the Epstein-Barr virus encoded EBNA1 contributes to the growth and survival of Hodgkin lymphoma cells". Blood. 111 (1): 292- ... Deletion of PTPkappa was shown to generate T-helper immunodeficiency in the LEC strain. By expressing a dominant negative form ... Downregulation of PTPkappa was found to occur following Epstein-Barr Virus (EBV) infection of Hodgkin's Lymphomas cells. Using ...

https://en.wikipedia.org/wiki/PTPRK

IL-12 in turn promotes the secretion of IFN-γ by NK cells and Th1 cells, and it signals naive T helper cells (Th0) to ... Portals: Biology Medicine Viruses (Articles with short description, Short description matches Wikidata, Articles to be merged ... The primary cells that secrete type II IFN are CD4+ T helper 1 (Th1) cells, natural killer (NK) cells, and CD8+ cytotoxic T ... Type II IFN is primarily secreted by adaptive immune cells, more specifically CD4+ T helper 1 (Th1) cells, natural killer (NK) ...

https://en.wikipedia.org/wiki/Interferon_type_II

For virus-associated tumors, such as cervical cancer and a subset of head and neck cancers, epitopes derived from viral open ... APCs then present the fragments to T helper cells (CD4+) by the use of class II histocompatibility molecules on their surface. ... This includes parts (coats, capsules, cell walls, flagella, fimbriae, and toxins) of bacteria, viruses, and other ... Some antigens start out as exogenous and later become endogenous (for example, intracellular viruses). Intracellular antigens ...

https://en.wikipedia.org/wiki/Antigen

In humans, the disease follows infection by the Crimean-Congo hemorrhagic fever virus (CCHFV) and begins as flu-like symptoms ... Memory CD4 T Cells Direct Protective Responses to Influenza Virus in the Lungs through Helper-Independent Mechanisms. J. Virol. ... Crimean-Congo hemorrhagic fever virus (CCHFV) is a tick-borne virus that can cause severe, hemorrhagic disease in humans. Along ... Swain, S.L.; McKinstry, K.K.; Strutt, T.M. Expanding roles for CD4+ T cells in immunity to viruses. Nat. Rev. Immunol. 2012, 12 ...

https://www.mdpi.com/2076-2607/9/2/279

A helper-dependent adenovirus vector system: Removal of helper virus by Cre-mediated excision of the viral packaging signal ...

https://experts.mcmaster.ca/display/publication243392

Chaturvedi UC, Pahwa M, Mathur A. Dengue virus-induced helper T cells. Indian Journal of Medical Research. 1987 Jul; 86(): 1-8 ...

https://imsear.searo.who.int/handle/123456789/25794

Tag Archives: corona virus reunion So Now What? Corona Virus and Your Family Reunion. Posted on April 30, 2020. by Aunt Mo ... Family Reunion Helper. Your number one source for family reunion organization. Search. ... corona virus reunion, covid 19 reunion, families reunion, family clipart, family gathering, family reunion, family reunion ...

http://familyreunionhelper.com/blog/tag/corona-virus-reunion/

How to remove Receiver Helper virus. What is Receiver Helper virus. Receiver Helper virus refers to a minor infection that ... What does Receiver Helper virus do?. You probably became aware of Receiver Helper when an alert appeared warning you that it ... Receiver Helper virus removal. You should move Receiver Helper to bin, as the alert suggests. However, to fully remove Receiver ... Moving it to the bin and deleting any associated programs should effectively remove Receiver Helper virus from your Mac. ...

https://www.mac-antivirus.com/how-to-remove-receiver-helper-virus/

Pseudorabies virus; Th: Helper T. ... Induction of higher virus-specific antibody titers and CD4+ T- ... Vaccinia virus challenge. Induction of a protective T-cell response. [191]. Attenuated Salmonella typhimurium vaccine strain ... Vaccinia virus expressing CCL21. Colon cancer CT26 cells. Enhanced infiltration of CD4+ T cells and inhibition of tumor growth ... CCL5-influenza virus HA fusion DNA construct. Viral influenza challenge. Half-life chemokine extension and production of mixed ...

https://www.medscape.com/viewarticle/772651

Stop Third-Party Anti-Virus. Some Antivirus programs dont let you disable them from within their own program. This is because ... How to Fix High CPU Use by Adobe CEF Helper?. Adobe Flash Player uses a helper application called Adobe CEF (Content Encryption ... Adobe Creative Suite 5 introduced a helper application called Adobe CEF Helper. This program ran in the background and handled ... Adobe CEF Helper High Memory or CPU Usage? [Quick Solution for Windows 10/11]. October 30, 2022. by Michael Harrington ...

https://www.microsoft-watch.com/adobe-cef-helper-high-memory-or-cpu-usage/

Note: CD4+ T-cells are T-helper cells. The correct cells to report for this value are those that are positive for both CD3 and ... Update: universal precautions for prevention of transmission of human immunodeficiency virus, hepatitis B virus, and other ... Inactivation of human T-lymphotropic virus type III/ lymphadenopathy-associated virus by formaldehyde-based reagents. Appl ... human T-lymphotropic virus type III/lymphadenopathy-associated virus) infection. J Clin Immunol 1987;7:140-50. ...

https://www.cdc.gov/mmwr/preview/mmwrhtml/00030802.htm

Temperature-sensitive mutants of murine leukemia virus. 3. Mutants defective in helper functions for sarcoma virus fixation. ... RNA-dependent DNA polymerase activity of RNA tumor viruses. V. Rous sarcoma virus single-stranded RNA-DNA covalent hybrids in ... reverse transcriptase of a mammalian leukemia virus mutant temperature sensitive in its replication and sarcoma virus helper ... reverse transcriptase of a mammalian leukemia virus mutant temperature sensitive in its replication and sarcoma virus helper ...

https://m.wikidata.org/wiki/Q36569334

Heterologous Hepatitis C Virus Infection in Chimpanzees Is Associated with the Quality of Vaccine-Induced Peripheral T-Helper ... Heterologous Hepatitis C Virus Infection in Chimpanzees Is Associated with the Quality of Vaccine-Induced Peripheral T-Helper ...

https://www.jenner.ac.uk/publications/111350?75955fa3-72d7-11ed-8572-061b866677b4

"There are viruses in bats that infect bats all the time," PhD. researcher Stephen Goldstein said. Dr. Goldstein says those ... viruses in bats and pangolins have an impact on humans. "But […] ... Research happening at the University of Utah links the coronavirus to viruses common in bats and pangolins. " ... Interview with Filmmaker and Santa Helper from "Believe: … 2 hours ago. .cls-3{fill:#fff;fill-rule:evenodd}. ...

https://www.abc4.com/coronavirus/u-of-u-research-links-covid-19-pandemic-to-viruses-found-in-bats-and-pangolins/

Since the recombinant viruses with AAV termini contained no sequence homology to the helper DNA, no wild-type AAV was generated ... Since the recombinant viruses with AAV termini contained no sequence homology to the helper DNA, no wild-type AAV was generated ... Since the recombinant viruses with AAV termini contained no sequence homology to the helper DNA, no wild-type AAV was generated ... Since the recombinant viruses with AAV termini contained no sequence homology to the helper DNA, no wild-type AAV was generated ...

https://collaborate.princeton.edu/en/publications/helper-free-stocks-of-recombinant-adeno-associated-viruses-normal

This post talks about the causes for computer viruses, and how Maxthon Cloud Browser helps enhance cyber and browser security, ... Tutu Helper says: May 9, 2017 at 9:19 am Wow! I am now shifting to Maxthon browser. Really wonderful post. Thanks a lot for ... How does your computer get viruses or malware?. For many people, the spread of computer viruses seems like a mystery because of ... from viruses, too. In this post, we will give a brief introduction about the causes for computer viruses, and how Maxthon Cloud ...

http://www.maxthon.com/blog/maxthon-secure-browser-web-without-viruses-malware/?replytocom=496721

Learn about using viruses as a cure for cancer. ... T helper cells. Biology Pages. http://users.rcn.com/jkimball. ... The injected virus goes after the cancerous cells, just as the virus in the Yale study. But the gene attached to the virus ... After all, to a natural antibody, a virus is a virus, even when its meant to perform a beneficial function. This leads to the ... Anthony van den Pol, used an existing virus related to rabies, the vesicular stomatitis virus -- as a weapon against cancerous ...

https://science.howstuffworks.com/life/cellular-microscopic/cure-for-cancer-virus.htm

Home › Blog › Unite to defeat the virus together! High-voltage cable is a good helper * Twitter ... Unite to defeat the virus together! High-voltage cable is a good helper. Posted by Amy on April 07, 2020. ... Everyone is equal before the virus, and no one can be alone. Now that the epidemic has not passed, we still have to strengthen ... and bucky stands can help people quickly detect viruses; collimators, high-voltage cables and other accessories are also on ...

https://www.xraycable.com/unite-to-defeat-the-virus-together-high-voltage-cable-is-a-good-helper.html

Increased T-helper cell activation, expression, recruitment, and cytotoxic activity. Blocked T-suppressor cell activity. ... Isolation of Hendra virus from pteropid bats: a natural reservoir of Hendra virus. J Gen Virol. 2000;81:1927-32 .PubMedGoogle ... Leroy EM, Kumulungui B, Pourrut X, Rouquet P, Hassanin A, Yaba P, Fruit bats as reservoirs of Ebola virus. Nature. 2005;438:575 ... Chua KB, Koh CL, Hooi PS, Wee KF, Khong JH, Chua BH, Isolation of Nipah virus from Malaysian Island flying foxes. Microbes ...

https://wwwnc.cdc.gov/eid/article/20/5/13-0539-t2

Failure to control virus is associated with emergence of dysfunctional CD4+ T-cell populations. Failure to control HCV in ... Cellular immune responses are thought to play a major role in control of the virus. Failure of CD4+ T-cell responses in acute ... We aimed to assess such responses using a novel set of Class II tetrameric complexes (tetramers) to study helper T-cells ex ... We were able to track the virus-specific CD4+ T-cells directly ex vivo with HLA DR4 tetramers. Proliferative responses were ...

https://www.immunology.ox.ac.uk/publications/15998

Human immunodeficiency virus (HIV)-specific T helper responses fail to predict CD4+ T cell decline following short-course ... Human immunodeficiency virus (HIV)-specific T helper responses fail to predict CD4+ T cell decline following short-course ...

https://www.expmedndm.ox.ac.uk/publications/1961?1af669c0-7489-11ed-8577-061b866677b4

1. SARS is caused by the infection with which type of virus?1/10. Aphthovirus. Coronavirus. Helper virus. Borna virus. ... SARS-Like Virus in Saudi and Qatar. The WHO has issued a warning about a new SARS-like virus, which has reportedly claimed six ... Patient Dies from SARS-like Virus. In Britain, a person suffering from a SARS-like virus has died, report health officials, ...

https://www.medindia.net/medical-quiz/quiz-on-sars.asp

This virus is bad. I have heard similar stories from other workshops, too. You never know how you can catch this virus. If this ... However, the young helper at my workshop caught coronavirus. … It took him a month to recover. I helped him financially during ... "I took every measure to make sure there was no risk of spreading the virus. I wore masks, I wore gloves. I even washed my hands ... Knowing that devices could carry viruses, they tried using gloves when touching them, but gloves were not always available and ...

https://www.iie.org/en/Programs/IIE-Centennial-Fellowship/Centennial-Fellows-Blogs/2019-Blog/Syed-Ishtiaque-Ahmed-3

Feedback Area • Herbs and Helpers INFO ALERT - Corona Virus (COVID19) !!! February 21, 2020. Herbs and Helpers INFO ALERT - ... The root extract can help treat HIV-1, the most common form of the virus. It contains a compound which prevents the virus ... Feedback Area • Herbs and Helpers INFO ALERT - Price Updates/VAT registered January 11, 2021. Herbs and Helpers INFO ALERT - ... Feedback Area • Herbs and Helpers INFO ALERT - New Premises Update November 29, 2020. Herbs and Helpers INFO ALERT - New ...

https://www.herbalmedicineuk.com/cure-aids-lie-geraniums-plant-extract-prevents-virus-invading-human-cells/

Quality tested and virus free. No ads, no adware, no spyware.. Your Security and Privacy are important to us! Privacy Policy ... everyone is looking for Helper as an accomplice to the crime!. Helper is in deep trouble and if he doesnt help catch the ... Rainbow Mosaics is back with an incredible new nonogram detective story! This time, Helper the Robot has, very unfortunately, ... been assigned to an unsavory character and Helpers own naivety works against him when he gets wrapped up in a shoplifting ...

https://www.bigfishgames.com/games/15315/rainbow-mosaics-13-detective-helper/?pc&lang=en

The ZAP70 gene is also involved in the activation of helper T cells (CD4+ T cells). These cells direct and assist the functions ... Children with SCID lack virtually all immune protection from bacteria, viruses, and fungi. They are prone to repeated and ... These include cytotoxic T cells (CD8+ T cells), whose functions include destroying cells infected by viruses. ...

https://medlineplus.gov/genetics/condition/zap70-related-severe-combined-immunodeficiency

HKEY_LOCAL_MACHINE\~\Browser Helper Objects\{C3E15DFE-D990-4C3F-9BE2-4CF4E3E007CE}]. [HKEY_LOCAL_MACHINE\~\Browser Helper ... Afgesloten topics virus- & malwareinfecties *Als dit je eerste bezoek is, raadpleeg de veelgestelde vragen via bovenstaande ... HKEY_LOCAL_MACHINE\~\Browser Helper Objects\{0FFA4CEC-B807-4734-B1E2-B7FA91C5C491}]. C:\WINDOWS\system32\cbXoMCrQ.dll. [HKEY_ ... Virus/Spyware Pop-Ups Traag ladend internet enz 26-04-08, 20:06. ... HKEY_LOCAL_MACHINE\~\Browser Helper Objects\{AB4B5A6B-04EF-4A6B ...

https://www.nucia.eu/forum/virus-en-malwareverwijdering/hulp-bij-virusinfecties/afgesloten-topics-virusinfecties/35588-virus-spyware-pop-ups-traag-ladend-internet-enz

Helper T lymphocytes express cluster determinant 4; CD8, cytotoxic T cells express cluster determinant 8; CDC, Centers of ... In silico analysis inferred the genetic variability among the tested viruses. The SARS-1 genome harbored 11 genes encoding 12 ... Emergence, evolution, and vaccine production approaches of SARS-CoV-2 virus: Benefits of getting vaccinated and common ... The traditional (killed or attenuated virus vaccine and antibody-based vaccine) and innovated vaccine production technologies ( ...

https://pubmed.ncbi.nlm.nih.gov/34924802/

And he had a key helper. "I had my girlfriend here who was giving me drinks and M&Ms." ... Confined by virus, Frenchman runs marathon on his 23-foot balcony. It took Elisha Nochomovitz six hours and 48 minutes to run ... And that has authorities worried that too many people are still out in the streets, threatening efforts to contain the virus. ... Nochomovitz wanted to show others that its possible to stay fit as virus containment measures tighten around the world. ...

https://www.wtol.com/article/news/nation-world/confined-by-virus-frenchman-runs-marathon-on-his-23-foot-balcony/507-676baf43-6a26-4462-936a-72876c4f101b

... viruses, worms: How does malware get on PCs and Macs? ... Proud Community Member&Helper.. * Re: Trojans, viruses, worms: ... Re: Trojans, viruses, worms: How does malware get on PCs and Macs? « Reply #1 on: June 22, 2011, 04:59:32 AM » ... Re: Trojans, viruses, worms: How does malware get on PCs and Macs? « Reply #2 on: June 22, 2011, 06:00:52 AM » ... Re: Trojans, viruses, worms: How does malware get on PCs and Macs? « Reply #3 on: June 22, 2011, 06:15:15 AM » ...

https://forum.avast.com/index.php?topic=80306.0

... posted in Virus, Spyware, Malware Removal: Hi,I am running Vista Ultimate 32 bit no service packs on a Dell desktop All-In-One. ... A92DAB39-4E2C-4304-9AB6-BC44E68B55E2} = Google Update Helper. {AC76BA86-7AD7-1033-7B44-AA0000000001} = Adobe Reader X (10.0. ... 2. Close/disable all anti virus and anti malware programs so they do not interfere with the running of ComboFix. 3. Open ... I ran the Kapersky Virus Removal Program. It flashed a screen informing me of a threat and suggested that I quarantine. It ...

http://www.geekstogo.com/forum/topic/300531-suspect-malware/

Forum Helper. Joined. Nov 25, 2013. Messages. 22,706. Purraise. 54,874. Location. Canada ...

https://thecatsite.com/threads/corona-virus-now-spreading.408746/page-237

... they are not always found within their helper viruses.[20]. *Satellite viruses[25]*Single-stranded RNA satellite viruses *( ... Measles virus, mumps virus, respiratory syncytial virus, Rinderpest virus, canine distemper virus Enveloped Helical ss(−) V ... and foot-and-mouth virus), SARS virus, hepatitis C virus, yellow fever virus, and rubella virus. ... DNA virusesEdit. Further information: DNA virus. Viruses with a DNA genome, except for the DNA reverse transcribing viruses, ...

https://en.m.wikipedia.org/wiki/Viral_species

In humans, the disease follows infection by the Crimean-Congo hemorrhagic fever virus (CCHFV) and begins as flu-like symptoms that can rapidly progress to hemorrhaging and death. (mdpi.com)
Receiver Helper virus refers to a minor infection that affects Mac computers. (mac-antivirus.com)
The recombinant virus gene was then used to generate drug-resistant human cell lines subsequent to infection. (princeton.edu)
Transient immunological control during acute hepatitis C virus infection: ex vivo analysis of helper T-cell responses. (ox.ac.uk)
Hepatitis C virus (HCV) readily sets up persistence after acute infection. (ox.ac.uk)
Rhesus macaques receiving a priming vaccine followed by multiple booster inoculations had a 79% lower per-exposure risk of infection by simian-human immunodeficiency virus (SHIV) compared to unvaccinated animals. (nih.gov)
They found it also protects blood and immune cells from infection by the virus. (herbalmedicineuk.com)
1. SARS is caused by the infection with which type of virus? (medindia.net)
Although guidelines have been established for prophylaxis against Pneumocystis carinii pneumonia (PCP) for adults with human immunodeficiency virus (HIV) infection, they have not been available for children (1). (cdc.gov)
Influenza viruses can persist on nonporous surfaces for 24 hours or more, but quantities of the virus sufficient for human infection are likely to persist for shorter periods. (cdc.gov)
Although the relative importance of virus transfer from inanimate objects to humans in spreading influenza is not known, hand transfer of the virus to the mucous membranes of the eyes, nose, and mouth resulting in infection is likely to occur. (cdc.gov)
Because of the high rate of asymptomatic infection with these viruses, information about the prevalence of these diseases is needed to monitor prevention efforts. (cdc.gov)
NHANES testing for markers of infection with hepatitis viruses is used to determine secular trends in infection rates across most age and racial/ethnic groups and will provide a national picture of the epidemiologic determinants of these infections. (cdc.gov)
however, highly effective, well-tolerated treatment can cure hepatitis C virus infection. (cdc.gov)
Hepatitis D virus infection is less common in the US and can occur only among persons with hepatitis B virus infection. (cdc.gov)
Co-infection with hepatitis D virus (HDV) in persons with acute or chronic hepatitis B virus (HBV) infection can lead to fulminant hepatitis. (cdc.gov)
Others are 'helper' T-cells that direct the assault of an infection or cancer. (verywellfit.com)
A new plant-derived natural small molecule, called neferine, was also identified as a potential entry inhibitor of the virus, and showed 75% inhibition of infection in cell cultures in a pseudovirus assay, by inhibiting calcium channels in the cell membrane. (news-medical.net)
Lymph node cells, regional to the site of infection with herpes simplex virus type 1 (HSV-1), when taken 1 to 9 months p.i. and transferred to HSV-1 immune recipients, suppressed the delayed type hypersensitivity (DTH) reaction to the virus. (microbiologyresearch.org)
Acute and recurrent infection with herpes simplex virus in the mouse: a model for studying latency and recurrent disease. (microbiologyresearch.org)
Role of T lymphocytes in cellular immune responses during herpes simplex virus infection in humans. (microbiologyresearch.org)
The aim of this study was to determine the efficacy of hepatitis B virus (HBV) vaccination and the response to vaccine in individuals on haemodialysis with and without HCV infection. (who.int)
Chronic hepatitis B virus (HBV) infection is one of the most important public health problems in Asia and developing countries [1]. (who.int)
Mechanism of recovery from acute virus infection. (elsevier.com)
Beginning on day 6 or 7 after infection, the foot undergoes a delayed-type hypersensitivity (DTH) reaction which consists of two distinct phases that are mediated by CD8 + cells and CD4 + cells, respectively, and at about the same time the virus is eliminated. (elsevier.com)
Dive into the research topics of 'Mechanism of recovery from acute virus infection. (elsevier.com)
Although influenza infection causes T helper-1 cells to produce interferon-gamma and promote up-regulation of T-bet by the B-cells and their differentiation into antibody secreting cells, not all pathogens induce T helper-1 cell development. (drugtargetreview.com)
These presentations have been described in children with influenza virus infection. (medscape.com)
Severe neurologic infection is more common when the virus is introduced in an area of nonendemic disease. (medscape.com)
In 1999, during the New York City outbreak of West Nile virus infection, 62 patients developed encephalitis, and 7 died (a case fatality rate of 12%, with all deaths occurring in older patients). (medscape.com)
Delayed weakness or recurrent clinical weakness after West Nile virus infection has been described. (medscape.com)

Since the recombinant viruses with AAV termini contained no sequence homology to the helper DNA, no wild-type AAV was generated by homologous recombination within infected cells. (princeton.edu)
4) they have no extensive sequence homology to the helper virus. (bvsalud.org)

When I was a boy and I would see scary things in the news, my mother would say to me, 'Look for the helpers. (styleweekly.com)
When he was a child whenever he was frightened by something he witnessed, his mother would address his fear with these words: Look for the helpers. (compassionfatigue.org)

After all, to a natural antibody, a virus is a virus, even when it's meant to perform a beneficial function. (howstuffworks.com)
Their results, published in Nature Medicine , show that the novel vaccine was safe and prompted desired antibody and cellular immune responses against an HIV-like virus. (nih.gov)
The traditional (killed or attenuated virus vaccine and antibody-based vaccine) and innovated vaccine production technologies (RNA- and DNA-based vaccines and viral vectors) are summarized in this review. (nih.gov)
Depletion, in infected mice, of all T lymphocytes by treatment with anti-Thy-1 monoclonal antibody prevented virus elimination from the foot, and the same was true when the CD8 + CTLs were removed. (elsevier.com)
Antibody-secreting cells are the cells that produce antibodies to fight invading pathogens like viruses. (drugtargetreview.com)
In accompanying experiments using influenza virus-infected mice, the Lund team found that B-cell intrinsic T-bet expression was required for the development of influenza-specific long-lived antibody-secreting cells, which provide protection from subsequent encounters with the virus. (drugtargetreview.com)
However, for T helper-2-induced B-cell response, the researchers found that T-bet was not required for B-cell differentiation into antibody-secreting cells. (drugtargetreview.com)
A blocking antibody is a specific type that works by preventing a bacterium or virus from attaching to a host cell. (thehealthboard.com)
By binding itself to the part of the bacterium or virus that is used to attach to host cells, the blocking antibody makes it difficult or impossible for the invader to harm its host. (thehealthboard.com)
An antibody is a protein produced by the immune system in response to a foreign invader, such as bacteria and viruses. (thehealthboard.com)
The T cells that help to produce antibodies, called T-helper cells, stimulate B cells to produce the blocking antibody specific to the antigen. (thehealthboard.com)
The T-helper cell then produces a chemical that stimulates the B cell to produce the antibody specific to that antigen. (thehealthboard.com)

Some are 'killer' T-cells that neutralize pathogens like bacteria, viruses, or fungi. (verywellfit.com)
The immune system is our body's defense system against infectious pathogenic viruses, bacteria, and fungi as well as parasitic animals and protists. (innerbody.com)
Neutrophil Netosis NETs have the effect of killing many pathogens, including bacteria (146), fungi (219), protozoans (220), and more recently viruses (221). (addresources.org)

The investigators used multiple virus variants to preferentially activate antibodies against the more conserved "shared" regions of the Env-the target of broadly neutralizing antibodies-rather than the more variable regions that differ in each virus strain. (nih.gov)
In addition to neutralizing antibodies, the VLP mRNA vaccine also induced a robust helper T-cell response. (nih.gov)
These involve tagging the viruses with antibodies, and killing those cells infected by the virus. (scienceabc.com)
The B lymphocyte produces antibodies, which bind to viruses and bacteria and target those pathogens for elimination. (drugtargetreview.com)
B cells produce antibodies by working in conjunction with the T-helper cells. (thehealthboard.com)

Cytotoxic T lymphocytes, natural killer (NK) cells and antiviral macrophages can recognize and kill virus-infected cells. (addresources.org)
These lymphocytes mature in the thymus and are responsible for killing cells infected with viruses. (primaryimmune.org)
The conclusion that here too the principal antiviral element is the CD8 + CTL was confirmed by experiments in which footpad-infected mice were adoptively immunized with virus-immune splenocytes from syngeneic mice selected for subclasses of T lymphocytes, or from mice differing in defined regions of the major histocompatibility complex (MHC), and also by experiments in which monocytes were virtually absent. (elsevier.com)

If you find yourself constantly getting pop-ups telling you about viruses, malware, etc., it could mean that your browser is infected. (microsoft-watch.com)
How does your computer get viruses or malware? (maxthon.com)
So to prevent viruses and malware, a secure internet browser is of significant importance. (maxthon.com)
First of all, Maxthon Cloud Browser has been tested by lots of 3rd party labs that it's clean of viruses and malware. (maxthon.com)
Many download sites will conduct tests on virus and malware before including certain software. (maxthon.com)
21st, 2017 with different anti-virus and anti-malware programs and services, Maxthon Cloud Browser was tested clean 100%, and does not contain any malware, spyware, Trojans or viruses. (maxthon.com)
Apart from anti-virus software, this download has also been tested with several popular anti-malware and anti-spam services. (maxthon.com)
Browsing with Maxthon Cloud Browser, annoying banners, pop-ups, malware and viruses are all blocked. (maxthon.com)
Visiting the wrong website, clicking the wrong link, or downloading the wrong file could all lead to a disastrous consequence Maxthon Cloud Browser is not only tested clean and without virus itself, it also helps prevent viruses and malware, bringing a secure internet environment for you. (maxthon.com)
Trojans, viruses, worms: How does malware get on PCs and Macs? (avast.com)
1. The traditional labels for malware categories-viruses, worms, Trojans, and so on-aren't nearly as meaningful as they were 10 years ago. (avast.com)
Malware like viruses is a sad fact of life in the modern world. (manilashaker.com)
Modern viruses can hide in Wi-Fi adapters and webcams, and malware can use onboard storage in modern peripherals to store itself. (manilashaker.com)
Common reasons include incorrect or failed installation or uninstallation of software that may have left invalid entries in your Windows registry, consequences of a virus or malware attack, improper system shutdown due to a power failure or another factor, someone with little technical knowledge accidentally deleting a necessary system file or registry entry, as well as a number of other causes. (fileerrors.com)
ItвЂ™s easy to start protecting your PC or laptop against viruses and malware with the latest version of Avast antivirus for Windows 7. (cnn.com)

Activation by antigen after immunization, antigen-specific suppressor and helper activities are mediated by distinct T-cell subclasses. (microbiologyresearch.org)
Instead, it first degrades the antigen and presents it to a T-helper cell. (thehealthboard.com)

SALT LAKE CITY, Utah (ABC 4 News)- Research happening at the University of Utah links the coronavirus to viruses common in bats and pangolins. (abc4.com)

T cells may act as helpers of other immune cells or attack pathogens directly. (innerbody.com)

That rise is reflected in many immigrant communities, where many people have lost jobs as domestic helpers, caregivers, and service workers in the restaurant and hospitality industries, and migrant farmworkers have faced an ongoing risk of contracting the virus and challenges accessing vaccines . (civileats.com)
The author of Man of Contradictions: Joko Widodo and the Struggle to Remake Indonesia , described the effect on the country as 'extremely concerning', adding that the 'majority of the workforce is employed informally' - motorcycle taxi drivers, domestic helpers, for example - professions that cannot work from home. (fcchk.org)

Although the helper DNA did not appear to replicate, it expressed AAV functions at a substantially higher level than did DNA molecules that contained neither AAV nor adenovirus termini. (princeton.edu)
If the virus can't replicate itself, then there's no need to worry about further problems. (scienceabc.com)

In 2019, the ICTV published a proposal to adopt a more formalized system of binomial nomenclature for virus species names, to be voted on in 2020. (wikipedia.org)
One such trojan-helper-emerged in 2019, and it targeted Android smartphones and successfully survived the factory reset. (manilashaker.com)

T-cells have receptors on them called T-cell receptors, which recognize viruses by their protein structure and alert other nearby immune cells that, "A virus has entered! (scienceabc.com)

Viruses are classified by phenotypic characteristics, such as morphology , nucleic acid type, mode of replication, host organisms , and the type of disease they cause. (wikipedia.org)
If nothing else, like macro viruses did a few years ago, it has increased the methods of virus replication and exposure. (mcpmag.com)

The virus activates a subset of T-helper cellscalled Th1cells. (prospecbio.com)
T follicular helper cell is considered to be involved in B cell and a subset of effector T cell maturing. (researchsquare.com)
Nodal peripheral T-cell lymphoma with T-follicular helper phenotype (NPTCL-TFH) is a subset of peripheral T-cell lymphoma defined by expression of at least 2 or 3 TFH markers. (researchsquare.com)
Depletion of the CD4 + helper/suppressor subset only marginally impaired the ability of the mice to rid themselves of the virus. (elsevier.com)

The effects of reciprocal changes in temperature on the transformed state of cells infected with a rous sarcoma virus mutant. (wikidata.org)
A type of immune cell that can attack foreign cells, cancer cells, and cells infected with a virus. (fpnotebook.com)

A method is described for the production of recombinant adeno-associated virus (AAV) stocks that contain no detectable wild-type helper AAV. (princeton.edu)

trans-Acting AAV functions were provided by a helper DNA in which the terminal 191 nucleotides of the AAV chromosome were substituted with adenovirus terminal sequences. (princeton.edu)

Cellular immune responses are thought to play a major role in control of the virus. (ox.ac.uk)
We aimed to assess such responses using a novel set of Class II tetrameric complexes (tetramers) to study helper T-cells ex vivo in acute disease. (ox.ac.uk)
Failure to control HCV in acute disease may relate to the capacity to sustain efficient immune responses as virus attempts to 'bounce back' after partial control. (ox.ac.uk)
Kapoor A. K. 1976 Lymphoid cell responses to herpes simplex virus Ph. (microbiologyresearch.org)

Cell-mediated immunity in herpes simplex virus- infected mice: induction, characterization and antiviral effects of delayed type hypersensitivity. (microbiologyresearch.org)
Acyclovir has demonstrated inhibitory activity against both herpes simplex virus type 1 (HSV-1) and herpes simplex virus type 2 (HSV-2) and is taken up selectively by infected cells. (medscape.com)
Herpes simplex virus type 1 (HSV-1) and herpes simplex virus type 2 (HSV-2) encephalitis have subacute forms, presenting with a psychiatric syndrome and an anterior opercular syndrome, known as benign recurrent meningitis. (medscape.com)

Human T-lymphotropic virus (HTLV) is a human, single-stranded RNA retrovirus that causes T-cell leukemia and T-cell lymphoma. (prospecbio.com)
As for a new umbrella category of PTCL, nodal peripheral T-cell lymphoma with T-follicular helper phenotype (NPTCL-TFH) was firstly classified in the 2017 revision of the World Health Organization (WHO) classification of hematolymphoid neoplasms. (researchsquare.com)
Current EPR priorities to improve these estimates include establishing the population attributable burden of HIV to cancer (e.g. cervical cancer, Kaposi sarcoma, non-Hodgkin lymphoma, anal cancer) and of Epstein-Barr virus to non-Hodgkin lymphoma and gastric carcinoma. (who.int)

Working hand-in-hand with MCI WorldCom, the only publicized victim of this virus so far, Network Associates is the lone vendor with a detector and removal process. (mcpmag.com)

Helper T cells can recognize virus-infected cells and produce a number of important cytokines. (addresources.org)
T-cells are also able to recognize virus-infected cells. (scienceabc.com)

Following are general guidelines for cleaning a truck cab after a truck arrives with a driver or helper suspected to have pandemic influenza 1 . (cdc.gov)

Note: Some commercial lysing/fixing reagents will reduce the infectious activity of cell-associated HIV by 3-5 logs (19), however, these reagents have not been evaluated for their effectiveness against other agents such as hepatitis virus. (cdc.gov)
Hepatitis viruses constitute a major public health problem because of the morbidity and mortality associated with the acute and chronic consequences of these infections. (cdc.gov)
In addition, NHANES provides the means to better define the epidemiology of other hepatitis viruses. (cdc.gov)
Hepatitis is inflammation of the liver most often caused by a virus. (cdc.gov)
Viral hepatitis is a major public health problem of global importance because of the ongoing transmission of viruses that cause the disease and increased morbidity and mortality associated with the acute and chronic consequences of these infections. (cdc.gov)
These five hepatitis viruses, also called hepatitides, are well-characterized for detection with laboratory assays and are monitored in U.S. public health surveillance systems. (cdc.gov)
An estimated 300 million people worldwide are persistent carriers of hepatitis B virus (HBV). (cdc.gov)
Ribavirin is used clinically in combination with interferon for hepatitis C, in aerosol form for respiratory syncytial virus (RSV), and as potential prophylaxis and/or treatment of Congo-Crimean hemorrhagic fever, hantavirus infections, and arenavirus hemorrhagic fevers. (medscape.com)

Focus formation and the generation of "nonproducer" transformed cell lines with murine and feline sarcoma viruses. (wikidata.org)
Failure to control virus is associated with emergence of 'dysfunctional' CD4+ T-cell populations. (ox.ac.uk)
They provide what's called cell-mediated immunity, which can become deficient in persons with HIV, the virus that causes AIDS. (medlineplus.gov)
We find that the initial B-cell clonal composition, T-follicular helper cell signaling, increased rounds of productive somatic hypermutation, and B-cell selection strength are among the mechanisms differentiating between strain-specific and broadly reactive plasma cell production during infections. (osti.gov)
With SARS-CoV-2, too, calcium-binding is considered to promote virus-host cell interactions. (news-medical.net)
In T-cell development, T-bet activates inflammatory gene programmes that allow the T-cells to become T helper-1, or Th1, cells that can kill viruses and bacteria. (drugtargetreview.com)
A macrophage engulfs an invading bacterium or virus and uses biochemical processes to break the cell into smaller units. (thehealthboard.com)

In an infected individual, the virus causes a depletion of subpopulation of T-cells, called T-helper cells, which leaves these patients susceptible to opportunistic infections, as well as certain malignancies. (cdc.gov)

Studies on reverse transcriptase of RNA tumor viruses III. (wikidata.org)
RNA-dependent DNA polymerase activity of RNA tumor viruses. (wikidata.org)

The Yale researchers, led by Dr. Anthony van den Pol, used an existing virus related to rabies, the vesicular stomatitis virus -- as a weapon against cancerous cells. (howstuffworks.com)
A range of sophisticated tools is needed to acquire this knowledge, and recombinant rabies virus (RABV) is becoming an increasingly important part of this essential toolbox. (frontiersin.org)
Rabies virus usually incubates for 20-60 days but is capable of incubating for years. (medscape.com)

Synthesizing a large body of recent research, Michael Cordingley goes beyond our familiarity with viral infections to show how viruses spur evolutionary change in their hosts, shape global ecosystems, and influence every domain of life. (nhbs.com)
even other viruses aren't spared from viral infections! (scienceabc.com)

Compared with other patients, Cluster 3 exhibited a unique gene expression pattern which was associated with changes in the glucocorticoid signaling and activation of the T helper 1/T helper 17 (T H 1/T H 17) immune pathways. (sinica.edu.tw)

As it worked its way through the brains of the mice, the virus killed only cancerous cells and left non-cancerous cells of the mice's own tissue as well as that grafted from human specimens intact. (howstuffworks.com)
Van den Pol and his group believe that the virus was able to reach the tumors located deep within the brains of the mice through leaky blood vessels in the tumors. (howstuffworks.com)
The Env proteins produced in the mice from the mRNA instructions closely resembled those in the whole virus, an improvement over previous experimental HIV vaccines. (nih.gov)

Reducing the number of influenza virus particles on a surface through these steps can reduce the chances of hand transfer of virus. (cdc.gov)

This document contains revised guidelines developed by CDC for laboratories performing lymphocyte immunophenotyping assays in human immunodeficiency virus-infected persons. (cdc.gov)
Human immunodeficiency virus (HIV) is a retrovirus that infects cells that possess the CD4 receptor (1-3). (cdc.gov)
Characterization of murine sarcoma virus (Kirsten) transformation of mouse and human cells. (wikidata.org)
When human cells were infected at a high multiplicity with a recombinant virus carrying a drug resistance marker gene, approximately 70% of the infected cells gave rise to colonies stably expressing the marker. (princeton.edu)
Because non-human primates are not susceptible to HIV-1, scientists use a chimeric SHIV in experimental settings because that virus replicates in macaques. (nih.gov)
Extracts of the geranium plant Pelargonium sidoides inactivate HIV-1 and prevent the virus invading human cells. (herbalmedicineuk.com)
They found that root extracts from the plants contain a compound that attacks HIV-1 and prevents the virus replicating inside the human body. (herbalmedicineuk.com)
In the last few decades, research has revealed that viruses are fundamental to the photosynthetic capacity of the world's oceans and the composition of the human microbiome. (nhbs.com)
Piecing together the story of viruses' major role within and beyond human disease, Viruses: Agents of Evolutionary Invention creates a valuable roadmap through the rapidly expanding terrain of virology. (nhbs.com)
This highly magnified transmission electron micrographic (TEM) image revealed the presence of mature forms of the human immunodeficiency virus (HIV) in a tissue sample under investigation. (cdc.gov)

Virus classification is the process of naming viruses and placing them into a taxonomic system similar to the classification systems used for cellular organisms . (wikipedia.org)

In this post, we will give a brief introduction about the causes for computer viruses, and how Maxthon Cloud Browser will help enhance your cyber and browser security and hence immune to such viruses. (maxthon.com)
For this program may be a helper for some cyber criminals who want to steal some confidential information and then user for marketing purpose. (blogspot.com)

They also act as signaling molecules that stimulate other immune cells, like Natural Killer cells , to attack the virus, and they alert surrounding cells that a virus has come to attack them. (scienceabc.com)

He said that the virus had increased Indonesia's reliance on China, with the country now waiting for a vaccine from Beijing. (fcchk.org)

Separation of murine cellular and murine leukaemia virus DNA polymerases. (wikidata.org)
Separation of helper T cells from suppressor T cells expressing different Ly components. (microbiologyresearch.org)

Small, linear single-stranded RNA molecules functionally acting as molecular parasites of certain RNA plant viruses. (bvsalud.org)

Leroy EM , Kumulungui B , Pourrut X , Rouquet P , Hassanin A , Yaba P , Fruit bats as reservoirs of Ebola virus. (cdc.gov)
Earlier, calcium channel blockers were successfully tested against flu viruses, the Japanese encephalitis virus, and the Ebola virus, among others. (news-medical.net)

A catalogue of all the world's known viruses has been proposed and, in 2013, some preliminary efforts were underway. (wikipedia.org)

It exerts its antiviral activity by selective inhibition at pyrophosphate-binding sites on virus-specific DNA polymerases at concentrations that do not affect cellular DNA polymerases, inhibiting DNA synthesis. (medscape.com)

The recombinant viruses contained only the terminal 191 nucleotides of the AAV chromosome bracketing a nonviral marker gene. (princeton.edu)

In silico analysis inferred the genetic variability among the tested viruses. (nih.gov)
Perhaps most fascinating, viruses are now recognized as remarkable engines of the genetic innovation that fuels natural selection and catalyzes evolution in all domains of life. (nhbs.com)

The cancerous cells were tagged with fluorescent proteins, as was the virus they injected into the mice's tails. (howstuffworks.com)
Muscle cells in an inoculated animal assemble these two proteins to produce virus-like particles (VLPs) studded with numerous copies of Env on their surface. (nih.gov)
There are many kinds of TLRs that are capable of spotting different parts of a virus, such as viral RNA or proteins. (scienceabc.com)

[9] Species names often take the form of [Disease] virus , particularly for higher plants and animals. (wikipedia.org)
And as more and more viruses jump to humans from other animals, new epidemics of viral disease will threaten global society. (nhbs.com)
Billions of us take medications on a regular basis, and while they help manage common conditions like viruses, depression, pain, menopause, thyroid disease, and the like, they are not so good for the environment. (weizmann-usa.org)

Influenza viruses are susceptible to inactivation by a number of chemical disinfectants readily available from consumer and commercial sources. (cdc.gov)

Temperature-sensitive mutants of murine leukemia virus. (wikidata.org)
Immunological characterization of a low molecular weight polypeptide of murine leukemia virus. (wikidata.org)

Acyclovir is also the drug of choice for varicella-zoster virus (VZV) encephalitis, although ganciclovir is also considered an alternative option. (medscape.com)

Moving it to the bin and deleting any associated programs should effectively remove Receiver Helper virus from your Mac. (mac-antivirus.com)

Dr. Goldstein says those viruses in bats and pangolins have an impact on humans. (abc4.com)

The formal taxonomic classification of viruses is the responsibility of the International Committee on Taxonomy of Viruses (ICTV) system, although the Baltimore classification system can be used to place viruses into one of seven groups based on their manner of mRNA synthesis. (wikipedia.org)
The International Committee on Taxonomy of Viruses began to devise and implement rules for the naming and classification of viruses early in the 1970s, an effort that continues to the present. (wikipedia.org)
MISSEL: a method to identify a large number of small species-specific genomic subsequences and its application to viruses classification. (cdc.gov)

Emotionally, this virus has been almost as virulent. (baptistnews.com)

Anatomy16

Organisms97

Diseases16

Chemicals and Drugs29

Analytical, Diagnostic and Therapeutic Techniques and Equipment22

Phenomena and Processes44

Technology, Industry, Agriculture1

Information Science4

New defective RNAs from citrus tristeza virus: evidence for a replicase-driven template switching mechanism in their generation. (1/552)

Virus promoters determine interference by defective RNAs: selective amplification of mini-RNA vectors and rescue from cDNA by a 3' copy-back ambisense rabies virus. (2/552)

Multiple mitochondrial viruses in an isolate of the Dutch Elm disease fungus Ophiostoma novo-ulmi. (3/552)

Frequency and stability of chromosomal integration of adenovirus vectors. (4/552)

Tamplicon-7, a novel T-lymphotropic vector derived from human herpesvirus 7. (5/552)

Interactions between tombusviruses and satellite RNAs of tomato bushy stunt virus: a defect in sat RNA B1 replication maps to ORF1 of a helper virus. (6/552)

Use of helper-dependent adenoviral vectors of alternative serotypes permits repeat vector administration. (7/552)

Delivery of herpes simplex virus amplicon-based vectors to the dentate gyrus does not alter hippocampal synaptic transmission in vivo. (8/552)

Helper Viruses

Defective Viruses

Virus Replication

RNA, Satellite

RNA Viruses

RNA, Viral

Satellite Viruses

Vaccinia virus

Plant Viruses

Genes, Viral

Virus Assembly

Reticuloendotheliosis virus

Viral Proteins

Genetic Vectors

DNA, Viral

Sarcoma Viruses, Murine

Simian virus 40

Friend murine leukemia virus

Dependovirus

Receptors, Virus

Moloney murine leukemia virus

Retroviridae

Virus Cultivation

T-Lymphocytes, Helper-Inducer

Cell Line

Virus Shedding

Virus Diseases

Viral Interference

Avian leukosis virus

DNA Viruses

Cell Transformation, Viral

Leukemia Virus, Murine

Sindbis Virus

Measles virus

Mosaic Viruses

Molecular Sequence Data

Gammaretrovirus

Influenza A Virus, H1N1 Subtype

Rabies virus

Vero Cells

Antigens, Viral

Influenza A Virus, H5N1 Subtype

Cercopithecus aethiops

Recombination, Genetic

Leukemia, Experimental

Virion

Tobacco Mosaic Virus

Hepatitis B virus

Influenza A Virus, H3N2 Subtype

West Nile virus

Respiratory Syncytial Viruses

Leukemia Virus, Feline

Murine Acquired Immunodeficiency Syndrome

Gene Expression Regulation, Viral

Base Sequence

Alpharetrovirus

Transfection

Plasmids

Herpesvirus 1, Human

Tumor Virus Infections

Virus Activation

Simplexvirus

Cells, Cultured

Cucumber Mosaic Virus Satellite

Adenoviridae

Vesicular stomatitis Indiana virus

Capsid

Cucumovirus

Tobacco

Virus Integration

Cytopathogenic Effect, Viral

Hemagglutinin Glycoproteins, Influenza Virus

Virus Latency

Abelson murine leukemia virus

Oncogenic Viruses

Genome, Viral

Simian immunodeficiency virus

Transcription, Genetic

Serial Passage

Sarcoma Virus, Woolly Monkey