• A therapeutic interfering particle is an antiviral preparation that reduces the replication rate and pathogenesis of a particular viral infectious disease. (wikipedia.org)
  • Similar to Defective Interfering Particles (DIPs), the agent competes with the pathogen within an infected cell for critical viral replication resources, reducing the viral replication rate and resulting in reduced pathogenesis. (wikipedia.org)
  • However, TIPs are engineered to retain specific elements of the genome that allow them to efficiently compete with the wild-type virus for critical replication resources inside an infected cell. (wikipedia.org)
  • TIPs thereby deprive wild-type virus of replication material through competitive inhibition, and therapeutically reduce viral load. (wikipedia.org)
  • However, when wild-type virus is present in the same cell (i.e., there is a superinfection of the cell), it provides the missing intracellular replication resources, allowing TIPs to conditionally replicate. (wikipedia.org)
  • Interference via competitive inhibition: TIPs reduce wild-type virus replication specifically by competing for intracellular viral replication resources (e.g., packaging proteins like the capsid). (wikipedia.org)
  • The rule of six, a basic feature for efficient replication of Sendai virus defective interfering RNA. (microbiologyresearch.org)
  • HIV persistence may arise from ongoing residual virus replication and/or from latently-infected cells defined as the cellular reservoir in which long-lived resting memory CD4+ T cells harbouring an integrated but transcriptionally silent provirus represent the largest pool in the blood (Chomont et al. (europa.eu)
  • However, while the late stages of the retrovirus life cycle, consisting of virus replication and egress, have been partly unraveled, the early steps remain largely enigmatic. (biomedcentral.com)
  • Retroviruses are enveloped RNA viruses defined by their mechanism of replication via reverse transcription to produce DNA copies that integrate into the host cell's genome. (msdmanuals.com)
  • Like all viruses, the EBOV largely relies on host cell factors and physiological processes for its entry, replication, and egress. (biomedcentral.com)
  • A therapeutic interfering particle is typically a biological agent (i.e., nucleic acid) engineered from portions of the viral genome being targeted. (wikipedia.org)
  • Therapeutic Interfering Particles, often referred to as TIPs, are typically synthetic, engineered versions of naturally occurring defective interfering particles (DIPs), in which critical portions of the virus genome are deleted rendering the TIP unable to replicate on its own. (wikipedia.org)
  • Often a TIP has the vast majority of the virus genome deleted. (wikipedia.org)
  • DIPs are spontaneously arising virus mutants, first described by von Magnus as "incomplete" viruses, in which a critical portion of the viral genome has been lost. (wikipedia.org)
  • It also exhaustively introduces the concrete mechanism of invading GC cells and the viral genome composition of adenovirus and herpes simplex virus type 1 (HSV-1). (frontiersin.org)
  • Retroviral particles must bind specifically to their target cells, cross the plasma membrane, reverse-transcribe their RNA genome, while uncoating the cores, find their way to the nuclear membrane and penetrate into the nucleus to finally dock and integrate into the cellular genome. (biomedcentral.com)
  • RNA viruses may escape acquired humoral and cellular immune responses by mutations in protective antigenic epitopes (e.g., avian influenza viruses), while accessory nonstructural proteins or multifunctional structural proteins interfere with the interferon system (e.g. (imperial.ac.uk)
  • BACKGROUND: Avian influenza (AI) virus detections occurred frequently in 2022 and continue to pose a health, economic, and food security risk. (cdc.gov)
  • Besides the virus inhibiting effect, the increased synthesis of mutant virions under the action of FPV possess a threat of the emergence of novel threatening viral strains with high pathogenicity for humans and animals and acquired resistance to chemotherapeutic compound. (crie.ru)
  • Increased or renewed reports of AI viruses, especially high pathogenicity H5N8 and H5N1 in birds and H5N1, H5N8, and H5N6 in humans globally, have established the need for a comprehensive review of current global AI virus surveillance data to assess the pandemic risk of AI viruses. (cdc.gov)
  • A total of 10 high pathogenicity AI and 6 low pathogenicity AI virus subtypes were reported to the WOAH for the first time during 2013-2022. (cdc.gov)
  • The vaccinia virus A56 protein was one of the earliest-described poxvirus proteins with an identifiable activity. (microbiologyresearch.org)
  • The A56 protein is capable of binding two viral proteins, a serine protease inhibitor (K2) and the vaccinia virus complement control protein (VCP), and anchoring them to the surface of infected cells. (microbiologyresearch.org)
  • While all coronaviruses contains these proteins, a subset (HEV, HCV-OC43 and BCV) is now recognized to possess an additional glycopolypeptide (gp65), which is unrelated to S or M. N protein The number of amino acids in the N protein has been determined by cloning and sequencing for MHV strains A59 (Armstrong et al. (pdfroom.com)
  • protective cytotoxic t-cell responses induced by venezuelan equine encephalitis virus replicons expressing ebola virus proteins. (liverpool.ac.uk)
  • Synthetic DIPs that rely on stimulating innate antiviral immune responses (i.e., interferon) were proposed for influenza in 2008 and shown to protect mice to differing extents but are technically distinct from TIPs due to their alternate molecular mechanism of action which has not been predicted to have a similarly high barrier to resistance. (wikipedia.org)
  • In molecular genetics terms, the wild-type virus is said to provide complementation in trans. (wikipedia.org)
  • Molecular cloning and characterization of a Sendai virus internal deletion defective RNA. (microbiologyresearch.org)
  • Molecular responses to influenza A virus (IAV) infections vary between mammalian species. (bvsalud.org)
  • We also provide evidence that virion-associated cholesterol contributes to the interaction between HCV particles and apolipoprotein E. The molecular basis for the effects of different sterols on HCV infectivity is discussed. (microbiologyresearch.org)
  • Intervention with therapeutic interfering particles can be prophylactic (to prevent or ameliorate the effects of a future infection), or a single-administration therapeutic (to fight a disease that has already occurred, such as HIV or COVID-19). (wikipedia.org)
  • The central requirement for a therapeutic interfering particle is that it mobilizes with a basic reproductive ratio (R0) that is greater than 1 (R0>1). (wikipedia.org)
  • 3) Permanent application of high therapeutic doses of FPV under the strict medical control to enhance the lethal mutagenic effect on an infectious virus in the recipient organism to prevent the multiplication of its mutant forms. (crie.ru)
  • The surge in Human Immunodeficiency Virus (HIV) research in order to identify new therapeutic targets has led to a better understanding of the retroviral life cycle. (biomedcentral.com)
  • Several clinical observations point to an intricate crosstalk between iron (Fe) metabolism and chronic hepatitis C virus (HCV) infection. (microbiologyresearch.org)
  • In order to better understand differences in the outcome of infectious bursal disease virus (IBDV) infection, we inoculated a very virulent (vv) strain into White Leghorn chickens of inbred line W that was previously reported to experience over 24% flock mortality, and three inbred lines (15I, C.B4 and 0) that were previously reported to display no mortality. (imperial.ac.uk)
  • METHODS: We analyzed AI virus infection reports among animals and humans submitted to animal and public health authorities from January 2013 to June 2022 and compared them with reports from January 2005 to December 2012. (cdc.gov)
  • Human immunodeficiency virus (HIV) infection results from 1 of 2 similar retroviruses (HIV-1 and HIV-2) that destroy CD4+ lymphocytes and impair cell-mediated immunity, increasing risk of certain infections and cancers. (msdmanuals.com)
  • Human Immunodeficiency Virus (HIV) Infection in Infants and Children Human immunodeficiency virus (HIV) infection is caused by the retrovirus HIV-1 (and less commonly by the related retrovirus HIV-2). (msdmanuals.com)
  • infection with ebola virus causes a severe disease accompanied by high mortality rates, and there are no licensed vaccines or therapies available for human use. (liverpool.ac.uk)
  • filovirus vaccine research efforts still need to determine the roles of humoral and cell-mediated immune responses in protection from ebola virus infection. (liverpool.ac.uk)
  • Many viruses, including Kaposi Sarcoma Herpesvirus (KSHV), have evolved sophisticated countermeasures to extend the life of an infected host cell to support establishment of infection and virus proliferation. (mdpi.com)
  • 2003. Ultrastructural differences in mixed infections of six Turnip mosaic virus and one Ribgrass mosic virus isolates in Crucifers. (esciencepress.net)
  • The most recent global analysis of official reports of animal outbreaks and human infections with all reportable AI viruses was published almost a decade ago. (cdc.gov)
  • Between January 2013 and June 2022, 17/194 (8.8%) World Health Organization (WHO) Member States reported 2000 human AI virus infections of 10 virus subtypes. (cdc.gov)
  • H7N9 (1568/2000, 78.40%) and H5N1 (254/2000, 12.70%) viruses accounted for the most human infections. (cdc.gov)
  • Seasonality patterns of animal outbreaks and human infections with AI viruses were very similar, occurred year-round, and peaked during November through May. (cdc.gov)
  • the status of current laboratory diagnostics for ebola and marburg virus infections is discussed in terms of the assays available and their interpretation. (liverpool.ac.uk)
  • Metazoans often trigger premature cell death in response to infections by larger DNA viruses as part of an immediate response to counter the viral threat. (mdpi.com)
  • 1995. An RNA-dependent RNA polymerase activity associated virions of tomato spotted wilt virus, a plant and insect-infecting Bunyavirus. (esciencepress.net)
  • Using the A/Puerto Rico/8/34 backbone, we generated a comprehensive panel of recombinant A(H3N2) viruses that have different NAs but shared an HA that displays poor binding to red blood cells (RBCs). (cdc.gov)
  • human recombinant antibodies to ebola virus: preparation and characteristics]. (liverpool.ac.uk)
  • human recombinant antibodies against a purified ebola virus (ev) lysate were selected from a combinatorial library of scfv-antibodies using the phage display technique. (liverpool.ac.uk)
  • ZMapp), anti-sense phosphorodiamidate morpholino oligomers (PMO AVI-6002), lipid nanoparticle small interfering RNA (LNP-siRNA: TKM-Ebola), and an EBOV glycoprotein-based vaccine using live-attenuated recombinant vesicular stomatitis virus (rVSV-EBOGP) or a chimpanzee adenovirus (rChAd-EBOGP)-based vector. (biomedcentral.com)
  • Additional representatives of the family reviewed in this article are the human (HCV) and bovine (BCV) coronaviruses, transmissible gastroenteritis virus (TGEV), haemagglutinating encephalitis virus (HEV) and feline infectious peritonitis virus (FIPV). (pdfroom.com)
  • In some areas of West Africa, both viruses are prevalent and may coinfect patients. (msdmanuals.com)
  • Substitutions at 148 and 151 arise from virus propagation in laboratory cell cultures, whereas changes at 150 occurred during virus evolution in the human host. (cdc.gov)
  • Substitution of Val 113 in Sendai virus (SeV) M protein generates non-functional polypeptides, characterized by their exclusion from virus particles and by their ability to interfere with virus particle production. (microbiologyresearch.org)
  • Analysis of the Sendai virus M gene and protein. (microbiologyresearch.org)
  • Sendai virus M protein is found in two distinct isoforms defined by monoclonal antibodies. (microbiologyresearch.org)
  • In addition, since the gene encoding the A56 protein is non-essential, it can be used as an insertion point for foreign genes and has been deleted in some viruses that are in clinical development as oncolytic agents. (microbiologyresearch.org)
  • Hepatitis E virus (HEV) ORF1 protein (pORF1) contains methyltransferase (MetT), papain-like cysteine protease (PCP), RNA helicase (Hel) and RNA-dependent RNA polymerase (RdRp) domains. (microbiologyresearch.org)
  • Influenza virus neuraminidase (NA) can act as a receptor-binding protein, a role commonly attributed to hemagglutinin (HA). (cdc.gov)
  • 1992. Characterization of distinct isolate of tomato spotted wilt virus TSWV. (esciencepress.net)
  • NA-binding was observed when a virus preparation contained approximately 10% of NA variants with either T148I or T439R, highlighting the benefit of using deep sequencing in virus characterization. (cdc.gov)
  • Immunoevasion is a common ploy by which viruses neutralize or evade immune responses. (imperial.ac.uk)
  • DNA viruses such as herpesvirus and poxvirus have multiple genes, some of them host-derived, which interfere with effective innate or acquired immune responses. (imperial.ac.uk)
  • Lv1 and Ref1 block incoming particles before reverse-transcription whereas Fv1 and Fv2 act at a stage between reverse-transcription and integration. (biomedcentral.com)
  • This review integrates most experimental studies and clinical trials of various oncolytic viruses (OVs) in the diagnosis and treatment of GC. (frontiersin.org)
  • Competitive inhibition enables TIPs to conditionally replicate and efficiently mobilize between cells, essentially "piggybacking" on wild-type virus, to act as single-administration antivirals with a high genetic barrier to the evolution of resistance. (wikipedia.org)
  • HIV-1 originated in Central Africa in the first half of the 20th century, when a closely related chimpanzee virus first infected humans. (msdmanuals.com)
  • nearly thirty years after the first epidemics, ebola virus (ebov) remains hardly described, its transmission unclear and its reservoir elusive. (liverpool.ac.uk)
  • soon after the ebola fever outbreak and virus discovery in 1976 and in order to investigate the distribution of ebov in central africa, several countries including a range of ecological zones were investigated in the early 1980s, using extensive survey: central african republic (car), cameroon, chad, congo, gabon and equatorial guinea. (liverpool.ac.uk)
  • The EBOV is an enveloped filamentous RNA virus belonging to the family Filoviridae . (biomedcentral.com)
  • During the long journey from the cell surface to the nucleus, retroviruses will face multiple obstacles, since in addition to finding a path through the cytoplasm to the nucleus they have to cross two main barriers, the plasma and nuclear membranes, whilst at the same time avoiding or counteracting cellular defences that can interfere with many of these steps. (biomedcentral.com)
  • in the past decade the zaire strain of ebola virus (zebov) has emerged repeatedly into human populations in central africa and caused massive die-offs of gorillas and chimpanzees. (liverpool.ac.uk)
  • ebola virus circulation in africa: a balance between clinical expression and epidemiological silence. (liverpool.ac.uk)
  • Most experimental data have been obtained from studies of mouse hepatitis virus (MHV) and infectious bronchitis virus of chickens (IBV). (pdfroom.com)
  • This mechanism of action reduces wild-type virus burst size and provides TIPs with a high genetic barrier to the evolution of viral resistance. (wikipedia.org)
  • Within each experimental group, some individuals experienced more severe disease than others but line 15I birds experienced milder disease based on average clinical scores, percentage of birds with gross pathology, average bursal lesion scores and average peak bursal virus titre. (imperial.ac.uk)
  • Further, in particular embodiments, the chimeric virus has a different immunological profile than one or both of the parent viruses (i.e., is only weakly or not at all recognized by neutralizing antisera or antibodies against the parent virus), thereby allowing for administration to subjects that have antibodies directed against the parent virus or repeat administration following administration of another serotype. (justia.com)
  • 1990. Serological differentiation of twenty of tomato spotted wilt virus. (esciencepress.net)
  • Mobilization with R0>1: when a TIP is conditionally activated by the wild-type "helper" virus in a super-infected cell, it will generate virus-like particles (VLPs). (wikipedia.org)
  • These TIP VLPs mobilize from the cell, are phenotypically identical to the virus being targeted, and can transduce new target cells. (wikipedia.org)
  • HA-M 30 is shown (i) to bind mainly to membrane fractions, (ii) not to co-precipitate M wt , as HA-M wt does, (iii) to interfere with the binding of nucleocapsids to membranes and (iv) to accumulate in perinuclear regions, in contrast to HA-M wt , which is also found at the cell periphery. (microbiologyresearch.org)
  • Our earlier study has demonstrated that hepatitis C virus (HCV)-associated cholesterol plays a key role in virus infectivity. (microbiologyresearch.org)
  • 1996. Occurrence of tomato spotted wilt virus in vegetables and ornamentals in Greece. (esciencepress.net)
  • RESULTS: From 2013 to 2022, 52.2% (95/182) of World Organisation for Animal Health (WOAH) Member Countries identified 34 AI virus subtypes during 21,249 outbreaks. (cdc.gov)
  • Microscopy of internal structures of Sendai virus associated with the cytoplasmic surface of host membranes. (microbiologyresearch.org)
  • lt;p>It is well known that viruses are obligate parasites entirely dependent on their host cells. (crie.ru)
  • Such dependence poses a serious challenge to drug developers in their attempts to create medications that are able to inhibit the target virus without having an adverse effect on biochemical processes of the host macroorganism. (crie.ru)
  • Such mutants constitute potential tools for the identification of critical steps in paramyxovirus assembly and budding. (microbiologyresearch.org)
  • Computer predictions of its secondary structure have led to a model in which approximately 10~ of the N-terminal part of the molecule is exposed on the outer surface of the virus membrane (see references above and Rottier et al. (pdfroom.com)
  • Defective forms of L-RNA containing core polymerase regions were observed. (esciencepress.net)
  • TIPs are built off the phenomenon of defective interfering particles (DIPs) discovered by Preben Von Magnus in the early 1950s, during his work on influenza viruses. (wikipedia.org)
  • As such, several VLP-based therapy proposals for influenza and other viruses that do not satisfy these criteria are DIPs, but not TIPs. (wikipedia.org)