• vectors
  • We have previously described avian leukosis virus-based packaging cell lines that express gag, pol, and env proteins from two transcomplementing genomes and produce helper-free stocks of retroviral vectors with different host ranges. (semanticscholar.org)
  • Gene transfer using replication-defective human foamy virus vectors. (uzh.ch)
  • Replication-defective vectors based on an infectious molecular clone of human foamy virus (HFV) were constructed by deletion and replacement of the accessory genes with expression cassettes for puromycin-resistance and beta-glucouronidase. (uzh.ch)
  • Replication-incompetent lymphocytic choriomeningitis virus (rLCMV) vectors do not elicit vector-neutralizing antibody responses, and homologous prime-boost regimens with rLCMV vectors induce boostable and protective T cell responses to model antigens in mice. (jpt.com)
  • Here we investigated CD8 + T cell responses in the female mouse cervicovaginal mucosa after intravaginal immunization with human papillomavirus vectors (HPV pseudoviruses) that transiently expressed a model antigen, respiratory syncytial virus (RSV) M/M2, in cervicovaginal keratinocytes. (jci.org)
  • Single-cycle viruses are also widely used as vaccine vectors, carrying genes from other viruses. (wikipedia.org)
  • Another reason these viruses are reliable vectors is the known insertion point for the genome. (wikipedia.org)
  • Gene therapy vectors using AAV can infect both dividing and quiescent cells and persist in an extrachromosomal state without integrating into the genome of the host cell, although in the native virus some integration of virally carried genes into the host genome does occur. (wikipedia.org)
  • To date, AAV vectors have been used in over 117 clinical trials worldwide, approximately 5.6% of virus-vectored gene-therapy trials. (wikipedia.org)
  • proteins
  • Researchers at Johns Hopkins and George Washington universities report new evidence that proteins created by defective forms of HIV long previously believed to be harmless actually interact with our immune systems and are actively monitored by a specific type of immune cell, called cytotoxic T cells. (eurekalert.org)
  • After verifying that defective HIV proviruses created HIV proteins, the researchers then tested whether human immune system cells could biologically recognize and interact with those proteins. (eurekalert.org)
  • The cytotoxic T lymphocytes' ability to identify and target the real threat appears to be greatly impaired, because they may attack proteins from defective proviruses instead of the real thing," says Ho. (eurekalert.org)
  • The defective ribosomal product (DRiP) hypothesis of endogenous Ag processing posits that rapidly degraded forms of nascent proteins are a major source of peptide ligands for MHC class I molecules. (jimmunol.org)
  • This rapidity of presentation, coupled with the relatively long half-life ( t 1/2 ) of most viral proteins, engendered the defective ribosomal product (DRiP) hypothesis of Ag presentation: a subset of newly synthesized proteins are defective in some manner and rapidly degraded intracellularly, yielding peptides for MHC class I Ag presentation to enable rapid immunosurveillance of viral and cellular translation products ( 2 ). (jimmunol.org)
  • Since the genome of the gutless virus does not include genes encoding the enzymes and/or structural proteins required to replicate, it is deemed safe for use in gene therapy since an infection cannot occur except in the presence of a suitable helper virus. (wikipedia.org)
  • Every cell that is successfully transfected with all three DNA fragments will produce the necessary proteins to produce infective viruses. (wikipedia.org)
  • However, this is only possible when the host cell is co-infected with a helper virus which provides functions it needs to be able to replicate which it does not code for in its own genome such as a reverse transcriptase and some major structural proteins. (wikipedia.org)
  • Biochemically, many viruses inhibit the synthesis of host DNA, RNA, proteins directly or even interfere with protein-protein, DNA-protein, RNA-protein interactions at the subcellular level. (wikipedia.org)
  • pathogen
  • Since Dmitri Ivanovsky 's 1892 article describing a non-bacterial pathogen infecting tobacco plants, and the discovery of the tobacco mosaic virus by Martinus Beijerinck in 1898, about 5,000 virus species have been described in detail, although there are millions of types. (wikipedia.org)
  • The human pathogen hepatitis D virus is a "defective" RNA virus similar to a viroid. (wikipedia.org)
  • adeno-assoc
  • Adeno-associated virus (AAV) is a small virus which infects humans and some other primate species. (wikipedia.org)
  • Because of AAV's specialized gene therapy advantages, researchers have created an altered version of AAV termed self-complementary adeno-associated virus (scAAV). (wikipedia.org)
  • gene
  • We can see from the gene sequence of the defective version that it is the same lineage and is a continued propagation of the virus," says Lloyd-Smith, who holds UCLA's De Logi Chair in Biological Sciences. (infectioncontroltoday.com)
  • We can see from the gene sequence of the defective version that it's the same lineage, and is a continued propagation of the virus," says Lloyd-Smith. (nsf.gov)
  • In evolution, viruses are an important means of horizontal gene transfer , which increases genetic diversity . (wikipedia.org)
  • One or more of the genes absolutely required for replication is deleted and the virus is grown in a cell line engineered to express these gene products. (wikipedia.org)
  • Using HSV-2, which causes genital herpes, they disabled the virus by deleting the viral gene encoding the membrane protein glycoprotein H (gH). (wikipedia.org)
  • this makes it a good virus to use as a gene therapy tool. (wikipedia.org)
  • One particularly promising method of IBV D-RNA-mediated heterologous gene expression uses the helper virus dependent system to promote IBV immunity. (wikipedia.org)
  • simian
  • Woolly monkey sarcoma virus (WMSV), with synonym Simian sarcoma virus (often abbreviated by SSV, but this may also stand for some species called 'Sulfolobus spindle-shaped virus', that belong to different genera in family Fuselloviridae) is a species of gammaretrovirus that infects primates. (wikipedia.org)
  • For its reproduction the virus needs a helper or associated virus which is called Simian sarcoma associated virus (SSAV). (wikipedia.org)
  • doi:10.1038/294273a0, alternatively at ResearchGate H. M. Fidanián, W. N. Drohán, M. A. Baluda: RNA of simian sarcoma-associated virus type 1 produced in human tumor cells, in: J Virol. (wikipedia.org)
  • Ruian Ke
  • We have shown that the defective virus not only transmits with the virus but increases the transmission of the functional virus," says Ruian Ke, a UCLA postdoctoral scholar in the department of ecology and evolutionary biology and the lead author of the study. (infectioncontroltoday.com)
  • We've shown that the defective virus not only goes with the normal virus, but increases the transmission of that virus," says scientist Ruian Ke, also of UCLA. (nsf.gov)
  • genetic
  • Aaskov and Holmes collected genetic sequences from from 15 people in Myanmar sampled over an 18-month period, all of whom were infected with the DENV-1 virus and nine of whom were also infected with the defective version. (infectioncontroltoday.com)
  • The scientists analyzed the genetic sequences of both the defective and normal dengue viruses to estimate how long the defective virus had been transmitting in the human population. (infectioncontroltoday.com)
  • Aaskov and Holmes collected genetic sequences from the defective viruses from 15 people sampled over an 18-month period in Myanmar. (nsf.gov)
  • Viruses are considered by some to be a life form, because they carry genetic material, reproduce, and evolve through natural selection, but lack key characteristics (such as cell structure) that are generally considered necessary to count as life. (wikipedia.org)
  • DIPs
  • The existence of DIPs has been known about for decades, and they can occur within nearly every class of both DNA and RNA viruses. (wikipedia.org)
  • DIPs have been shown to play a role in pathogenesis of certain viruses. (wikipedia.org)
  • UCLA
  • Defective viruses, thought for decades to be essentially garbage unrelated to the transmission of normal viruses, now appear able to play an important role in the spread of disease, new research by UCLA life scientists indicates. (infectioncontroltoday.com)
  • In findings published Feb. 28 in the journal PLoS Pathogens, UCLA scientists and their colleagues report for the first time a significant link between a defective virus and an increased rate of transmission of a major disease. (infectioncontroltoday.com)
  • The idea has always been that defective viruses are either meaningless or detrimental," says James O. Lloyd-Smith, a UCLA assistant professor of ecology and evolutionary biology and the senior author of the research. (infectioncontroltoday.com)
  • The idea has always been that defective viruses are either meaningless or detrimental," says James Lloyd-Smith, an ecologist and evolutionary biologist at the University of California, Los Angeles (UCLA). (nsf.gov)
  • genes
  • Although there is broad experimental support for the DRiP hypothesis, careful kinetic analysis of the generation of defined peptide class I complexes has been limited to studies of recombinant vaccinia viruses expressing genes derived from other organisms. (jimmunol.org)
  • herpes
  • Since moving to Cambridge, Minson's research has focused on animal viruses, particularly those of the herpesvirus family, including herpes simplex virus (HSV) and human cytomegalovirus. (wikipedia.org)
  • Following the completion of his graduate studies, he trained as post-doctoral fellow on molecular genetics of herpes simplex virus (HSV) at the University of Chicago with Dr. Bernard Roizman. (wikipedia.org)
  • cells
  • The origins of viruses in the evolutionary history of life are unclear: some may have evolved from plasmids -pieces of DNA that can move between cells-while others may have evolved from bacteria. (wikipedia.org)
  • In the study, the scientists collected nine different defective HIV proviruses from six people infected with HIV, then transfected cultures of human immune cells with them in the laboratory. (eurekalert.org)
  • The group again transfected cells in the lab with 6 different types of defective HIV provirus taken from patients. (eurekalert.org)
  • This product is not required until after the viral assembly process, which means that the disabled virus can undergo a single round of replication in normal human cells, but the progeny virus cannot infect new cells. (wikipedia.org)
  • The Abelson murine leukemia virus (Ab-MLV or A-MuLV) is a retrovirus (Class VI) used to induce transformation of murine lymphoid cells. (wikipedia.org)
  • Natural transformations can include viral cancers, such as human papillomavirus (HPV) and T-cell Leukemia virus type I. Hepatitis B and C are also the result of natural viral transformation of the host cells. (wikipedia.org)
  • infects
  • The dengue virus infects between 50 million and 100 million people each year in Southeast Asia, South America, parts of the United States and elsewhere. (infectioncontroltoday.com)
  • Dengue virus infects some 50-100 million people annually in Southeast Asia, South America and parts of the United States. (nsf.gov)
  • 2001
  • In a paper published this week in the journal PLoS Pathogens, scientists funded by the National Science Foundation (NSF) report a significant link between one such defective virus and the high rate of transmission of DENV-1 in Myanmar in 2001. (nsf.gov)
  • 1892
  • In 1892, the Russian biologist Dmitri Ivanovsky used this filter to study what is now known as the tobacco mosaic virus. (wikipedia.org)
  • Discovery of the viroid triggered the third major extension of the biosphere in history to include smaller lifelike entities--after the discovery of the "subvisible" microorganisms by Antonie van Leeuwenhoek in 1675 and the "submicroscopic" viruses by Dmitri Iosifovich Ivanovsky in 1892. (wikipedia.org)
  • Parvoviridae
  • Within the family parvoviridae, the dependovirus genus was given a distinct classification due to their dependence on another virus. (wikipedia.org)
  • Brain
  • Major has been quoted extensively in news coverage of the finding that natalizumab (Tysabri) and related monoclonal antibody-based therapies increase the risk of a rare brain disease caused by JC virus. (wikipedia.org)
  • vesicular
  • his thesis research focused on vesicular stomatitis virus (VSV) under the supervision of Dr. David Baltimore and Dr. Harvey Lodish. (wikipedia.org)
  • Antigens
  • Lastly, biologic effects include the viruses' ability to affect the activity of antigens and immunologlobulins in the host cell. (wikipedia.org)
  • progeny
  • Chronic infections have similar cellular effects as acute cytocidal infections but there is a limited number of progeny and viruses involved in transformation. (wikipedia.org)
  • generate
  • The single-cycle strategy can be used to generate live vaccines against other viruses, and such a vaccine has recently been successfully developed for bluetongue virus of sheep. (wikipedia.org)
  • As cogently expressed by Flores et al: Viruses (and viroids) share the most characteristic property of living beings: In an appropriate environment, they are able to generate copies of themselves, in other words, they are endowed with autonomous replication (and evolution). (wikipedia.org)