• 2008). Structures and mechanisms of viral membrane fusion proteins: multiple variations on a common theme. (tcdb.org)
  • This immune response is dominated by antibodies that target a common family of proteins called hemagglutinins (HA). (asm.org)
  • The surface of flu viruses is studded with proteins called hemagglutinins, which are the part of the virus that binds to cells in a person's respiratory tract, initiating infection. (foxnews.com)
  • A number of enveloped viruses confer fusion of the viral envelope and the cell membrane using surface viral fusion proteins. (bvsalud.org)
  • The first section of this review describes types of viral fusion proteins and is followed by a comparison of the structural features of class I fusion proteins, namely influenza virus hemagglutinin and the S-protein of the human coronavirus. (bvsalud.org)
  • Proteins associated with the inner surface of the lipid bilayer of the viral envelope. (lookformedical.com)
  • These proteins have been implicated in control of viral transcription and may possibly serve as the "glue" that binds the nucleocapsid to the appropriate membrane site during viral budding from the host cell. (lookformedical.com)
  • citation needed] Some hepatitis C viral glycoproteins may attach to C-type lectins on the host cell surface (liver cells) to initiate infection. (wikipedia.org)
  • Because of the important role of NS1 during viral infection, many attempts have been made to develop antiviral therapeutics targeting NS1. (datexis.com)
  • Measles is the most contagious airborne viral infection and the leading cause of child death among vaccine-preventable diseases. (bvsalud.org)
  • His work covers various topics, including B cell responses to viral infection and vaccination, human primary immunodeficiency, and biology of lymphocyte development and function and to elucidate etiology of immunological disorders. (stanford.edu)
  • We discuss the different vectored vaccines that have been or are currently in clinical trials, with a forward-looking focus on immunogens that may be protective against seasonal and pandemic influenza infection, in the context of viral-vectored vaccines. (mdpi.com)
  • To evade host's innate immune response, influenza has evolved a few strategies for viral replication. (datexis.com)
  • We also found that viral replication was suppressed in the presence of aptamers, which suggests that the selected RNA aptamers can be developed as a useful therapeutic agent in future. (datexis.com)
  • In eukaryotes, subsequent activation and viral replication is thought to be caused by extracellular stimulation of cellular transcription factors. (lookformedical.com)
  • But NAs have a lower rate of mutation than HAs, which suggests that a flu vaccine that contains NA - prompting the immune system to produce NA antibodies -- may be effective for multiple years, said Martinez-Sobrido. (asm.org)
  • The marrow continued to produce these NA antibodies with anti-viral activity, suggesting that a vaccine strategy based on NA responses could be long-lasting. (asm.org)
  • Antibodies that recognize and neutralize the hemagglutinin stalk should, in theory , work against multiple strains of flu. (foxnews.com)
  • In vitro selection of virus variants with representative monoclonal antibodies revealed that a single amino acid replacement at residue K163 in the Sa antigenic site, which is characteristic of the clade 6B viruses, was responsible for resistance to neutralization by multiple monoclonal antibodies and the donor serum. (ox.ac.uk)
  • Host immunity affects disease severity, disease duration, and vaccine response with regard to influenza virus infections and viral pathogenesis. (cdc.gov)
  • Immune responsiveness declines in the elderly as a consequence of alterations in the distribution and function of immune cells with age and changes induced by chronic viral infections (such as cytomegalovirus) and inflammatory diseases ( 1 , 2 ). (frontiersin.org)
  • They are important during viral infections and cancer. (biomedcentral.com)
  • Whether and how exposure to diesel exhaust particles (DEP) affects NK cell function in the context of viral infections has not been investigated. (biomedcentral.com)
  • This reduction in the potential ability of NK cells to kill virus-infected host cells may increase the susceptibility to viral infections after DEP exposure. (biomedcentral.com)
  • 2017). Comparative Study of Fusogenic Activity of H1 and H5 Subtypes Influenza Virus Hemagglutinins. (tcdb.org)
  • Thus far, influenza is classified on the subtypes of 18 hemagglutinins and 11 neuraminidases (Tong et al. (datexis.com)
  • Traditionally, the vaccine was trivalent (ie, designed to provide protection against three viral subtypes, generally an A-H1, an A-H3, and a B). The first quadrivalent vaccines, which provide coverage against an additional influenza B subtype, were approved in 2012 and were made available for the 2013-2014 flu season. (medscape.com)
  • Cyclophilin A (CypA), which has peptidyl-prolyl cis-trans isomerase (PPIase) activity, regulates multiple functions of cells by binding to its extracellular receptor CD147. (bvsalud.org)
  • Unfortunately, influenza vaccine composition needs to be updated annually due to antigenic shift and drift in the viral immunogen hemagglutinin (HA). (mdpi.com)
  • Here, we characterized variations in the major viral antigenic sites among contemporary RSV sequences when compared with RSVPreF3 and showed that, in older adults, RSVPreF3-AS01 broadly boosts neutralization responses against currently dominant and antigenically distant RSV strains. (bvsalud.org)
  • Influenza virus hemagglutinin (HA) is a type I (Class I) viral membrane fusion protein (VMFP), best characterized of its class. (tcdb.org)
  • This multivalent attachment by multiple copies of trimetric HA triggers endocytosis of influenza virus that is contained in the endosome. (tcdb.org)
  • There are a number of alternate vaccination strategies in current development which may circumvent the need for annual re-vaccination, including new platform technologies such as viral-vectored vaccines. (mdpi.com)
  • Multiple viruses, including influenza and several viruses in the Paramyxoviridae family, use this mechanism to bind and gain entry to target cells. (wikipedia.org)
  • The fusion of viral and cell membranes is one of the basic processes in the life cycles of viruses. (bvsalud.org)
  • The K163 residue lies in a part of a conserved surface that is common to the hemagglutinins of the 1977 and 2009 H1N1 viruses. (ox.ac.uk)
  • We describe the first report of RNA sequencing of 5' capped (Pol II) RNAs isolated from acutely hepatitis C virus (HCV) infected Huh 7.5 cells that provides a general approach to identifying differentially expressed annotated and unannotated genes that participate in viral-host interactions. (mdpi.com)
  • Like all Class I VMFPs, it requires proteolytic processing to generate the fusion competent form and is found on the virion projecting from the viral membrane as spikes. (tcdb.org)
  • To avoid clearance from the body by the innate immune system, pathogens (e.g., virus particles and bacteria that infect human cells) often express surface lectins known as adhesins and hemagglutinins that bind to tissue-specific glycans on host cell-surface glycoproteins and glycolipids. (wikipedia.org)
  • The in vitro and clinical testing of these possibilities can be sharpened by the incorporation of an existing anti-COVID-19 therapeutic that has been found in silico to competitively bind to multiple glycans on SARS-CoV-2 spike protein. (bvsalud.org)
  • Their conformational rearrangements lead to the unification of lipid bilayers of cell membranes and viral envelopes and the formation of fusion pores through which the viral genome enters the cytoplasm of the cell. (bvsalud.org)
  • In mink infected with chicken/49 no signs of disease were observed, while the mink infected with mink/84 showed severe signs of respiratory disease, with inflammatory lesions spreading throughout the lung and viral antigen present in substantial numbers of cells in the lung, nasal mucosa, and trachea. (biomedcentral.com)
  • A deep understanding of all the stages of conformational transitions preceding the fusion of viral and cell membranes is necessary for the development of specific inhibitors of viral reproduction. (bvsalud.org)
  • To evaluate the potential of R1a-B6 for immunoprophylaxis, we have reformatted it as an Fc fusion for adeno-associated viral (AAV) vector delivery. (frontiersin.org)
  • One explanation of the NS1 function is sequestration of viral RNA, which leads to inhibition of main viral RNA sensor RIG-I in the host cell (Chien et al. (datexis.com)
  • In fact, NS1 has multiple functions in infected cells. (datexis.com)
  • NK cells were isolated from peripheral blood obtained from normal healthy volunteers and subsequently stimulated with the viral mimetic polyinosinic:polycytidylic acid (pI:C), DEP, or pI:C+DEP for 18 hours. (biomedcentral.com)
  • Because of the relatively weak protective antibody response to influenza A(H7N9), multiple vaccinations might be needed to achieve protective immunity. (cdc.gov)
  • A series of articles devoted to influenza started with this introductory review of the history of this viral illness. (medscape.com)
  • An attractive option would be a "universal" vaccine that is based on antigens shared by multiple or even all influenza viruses. (medscape.com)
  • Multiple viruses, including influenza and several viruses in the Paramyxoviridae family, use this mechanism to bind and gain entry to target cells. (wikipedia.org)
  • According to this explanation, human influenza virus undergoes rapid antigenic drift because most neutralizing antibodies target epitopes on the viral hemagglutinin (HA) protein that are highly tolerant of mutational change. (nature.com)
  • Because of the relatively weak protective antibody response to influenza A(H7N9), multiple vaccinations might be needed to achieve protective immunity. (cdc.gov)
  • Host immunity affects disease severity, disease duration, and vaccine response with regard to influenza virus infections and viral pathogenesis. (cdc.gov)
  • H1N1 influenza is a subtype of influenza A virus, a communicable viral illness which causes upper and in some cases lower respiratory tract infections in its host. (nih.gov)
  • H1N1 Swine flu is a subtype of influenza A virus (a communicable viral disease), which causes upper, and potentially, lower respiratory tract infections in the host it infects, resulting in symptoms such as nasal secretions, chills, fever, decreased appetite, and possibly lower respiratory tract disease. (nih.gov)
  • 1. Membrane-Tethered Mucin 1 Is Stimulated by Interferon and Virus Infection in Multiple Cell Types and Inhibits Influenza A Virus Infection in Human Airway Epithelium. (nih.gov)
  • 8. Influenza A Virus-Induced Expression of a GalNAc Transferase, GALNT3, via MicroRNAs Is Required for Enhanced Viral Replication. (nih.gov)
  • 15. Influenza A Virus Dysregulates Host Histone Deacetylase 1 That Inhibits Viral Infection in Lung Epithelial Cells. (nih.gov)
  • 17. Influenza A virus-induced degradation of eukaryotic translation initiation factor 4B contributes to viral replication by suppressing IFITM3 protein expression. (nih.gov)
  • Important developments in vaccine production include construction and pretesting against all surface glycoproteins, including 16 hemagglutinins and 9 neuraminidases. (medscape.com)
  • citation needed] Some hepatitis C viral glycoproteins may attach to C-type lectins on the host cell surface (liver cells) to initiate infection. (wikipedia.org)
  • To avoid clearance from the body by the innate immune system, pathogens (e.g., virus particles and bacteria that infect human cells) often express surface lectins known as adhesins and hemagglutinins that bind to tissue-specific glycans on host cell-surface glycoproteins and glycolipids. (wikipedia.org)
  • Increased viral polymerase activity mediates adaptation of AIVs to a mammalian host 26 . (nature.com)
  • We describe interactions between the S protein and cellular receptors, co-receptors, and antagonists, as well as a hypothetical mechanism of the homotrimeric spike structure destabilization that triggers the fusion of the viral envelope with the cell membrane at physiological pH and mediates the viral nucleocapsid entry into the cytoplasm. (bvsalud.org)
  • Mechanisms of death include primary viral pneumonia, secondary bacterial pneumonia, and acute respiratory distress syndrome (ARDS). (medscape.com)
  • These data support an infectious process rather than transit of ingested infected material through the digestive tract as the source of viral RNA, particularly because this bat species does not feed on other vertebrates. (bioseek.eu)
  • Due to the particularity of blood products, there is a potential risk of viral contamination. (nih.gov)
  • As the carcinogenic potential of viral agents and H. pylori has been reviewed extensively elsewhere, it will not be included here. (biomedcentral.com)
  • This virus caused similar symptoms to those seen in swine, possibly due to reassortment of the viral RNA structure, which allowed human-to-human transfer. (nih.gov)
  • S. aureus can survive within multiple human cell types. (nih.gov)
  • Viral sequence data are available for the 1918 virus and showed that it was novel to humans. (medscape.com)