• In addition to the homotrimeric core structure, hemagglutinins have four subdomains: the membrane-distal receptor binding R subdomain, the vestigial domain E, that functions as a receptor-destroying esterase, the fusion domain F, and the membrane anchor subdomain M. The membrane anchor subdomain forms elastic protein chains linking the hemagglutinin to the ectodomain. (wikipedia.org)
  • Unfortunately, influenza vaccine composition needs to be updated annually due to antigenic shift and drift in the viral immunogen hemagglutinin (HA). (mdpi.com)
  • Influenza virus hemagglutinin (HA) is a type I (Class I) viral membrane fusion protein (VMFP), best characterized of its class. (tcdb.org)
  • It contains many strains as well as antigenic subtypes of the integral membrane proteins hemagglutinin ( VIRAL HEMAGGLUTININS ) and NEURAMINIDASE . (nih.gov)
  • 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)
  • Anti-viral antibodies were determined by inhibition of haemagglutination. (urosario.edu.co)
  • This immune response is dominated by antibodies that target a common family of proteins called hemagglutinins (HA). (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)
  • The Krammer laboratory (along with others) has demonstrated the existence of cross-reactive and cross-neutralizing antibodies against divergent hemagglutinins (HAs) and neuraminidases (NAs) in humans. (mssm.edu)
  • Hemagglutinins are responsible for binding to receptors on red blood cells to initiate viral attachment and infection. (wikipedia.org)
  • 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)
  • It has been previously demonstrated that the use of replication-defective viruses, such as lentiviral vectors pseudotyped with influenza A hemagglutinins in microneutralization assays (pMN) is a safe and sensitive alternative to study antibody responses elicited by natural influenza infection or vaccination. (ox.ac.uk)
  • The viral hemagglutinins of conventional influenza A viruses (IAVs) bind to sialylated glycans on host cell surfaces for attachment and subsequent infection. (figshare.com)
  • Structures of viral proteins help us discover effective ways to fight infection. (rcsb.org)
  • Today, with our continually growing understanding of virus structure and biology, we have many tools to fight viral infection. (rcsb.org)
  • This page explores some of the insights provided by structural biology about viruses and how these insights are used to develop new defenses against viral infection. (rcsb.org)
  • Measles is the most contagious airborne viral infection and the leading cause of child death among vaccine-preventable diseases. (bvsalud.org)
  • Because of the important role of NS1 during viral infection, many attempts have been made to develop antiviral therapeutics targeting NS1. (datexis.com)
  • 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)
  • 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)
  • LABEL: fast and accurate lineage assignment with assessment of H5N1 and H9N2 influenza A hemagglutinins. (cdc.gov)
  • 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)
  • 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)
  • It is a prodrug which inhibits cap-dependent endonuclease, an enzyme specific to influenza, resulting in inhibition of viral replication. (medscape.com)
  • Antiviral drugs block key viral proteins, preventing their replication and spread, and vaccines prime our immune system to make us ready for future exposure to common viruses. (rcsb.org)
  • 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)
  • She then integrated the Viroscience Department for her post-doctoral studies, which have focused on the pathogenesis, virulence and transmissibility of influenza A viruses, with special emphasis on genetic and phenotypic viral factors involved in the emergence of new pandemics. (erasmusmc.nl)
  • The fusion of viral and cell membranes is one of the basic processes in the life cycles of viruses. (bvsalud.org)
  • A number of enveloped viruses confer fusion of the viral envelope and the cell membrane using surface viral fusion proteins. (bvsalud.org)
  • 2008). Structures and mechanisms of viral membrane fusion proteins: multiple variations on a common theme. (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)
  • 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)
  • For this reason, seasonal vaccines need to be annually reformulated based upon the forecasting of viral strains that will circulate in the coming influenza season. (distantreader.org)
  • 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)
  • For example, circoviruses get by with only two genes: one to encode the capsid protein that will protect and deliver the genome in the infectious virus, and a replicase protein that hijacks cellular polymerases to create new copies of the viral single-stranded DNA genome. (rcsb.org)
  • Often, viral genes encode proteins with several functionalities, or genes for different proteins overlap with one another. (rcsb.org)
  • Nuclear antigens encoded by VIRAL GENES found in HUMAN HERPESVIRUS 4. (lookformedical.com)
  • Duck viral hepatitis (DVH) is an acute, highly contagious, viral disease typically affecting ducklings less than six weeks of age. (msdvetmanual.com)
  • Proteins associated with the inner surface of the lipid bilayer of the viral envelope. (lookformedical.com)
  • 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)
  • The originally described, most widespread, and most virulent subtype of duck viral hepatitis, traditionally referred to as DVH Type I, has been renamed duck hepatitis A virus type 1 (DHAV-1) and is now classified in the genus Avihepatovirus in the Picornaviridae family. (msdvetmanual.com)
  • In 1906, Paschen created a staining method for viral particles and demonstrated the elementary bodies (Paschen bodies) in smallpox lesion smears. (microbiologynote.com)
  • In the endosome, hemagglutinins are activated at a pH of 5 - 6.5 to undergo conformational changes that enable viral attachment through a fusion peptide. (wikipedia.org)
  • 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)
  • Development of Lentiviral Vectors Pseudotyped With Influenza B Hemagglutinins: Application in Vaccine Immunogenicity, mAb Potency, and Sero-Surveillance Studies. (ox.ac.uk)
  • Gp120-alum boosting of a Gag-Pol-Env DNA/MVA AIDS vaccine: poorer control of a pathogenic viral challenge. (ucdenver.edu)
  • The structure of the viral NA is also highly conserved, making it an attractive vaccine target. (mssm.edu)
  • 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)
  • In this context, viral entry was supported only by a chimera containing the HLA-DR α1, α2, and β1 domains. (figshare.com)
  • After recognition of viral RNA harboring 5′-triphosphate by RIG-I, CARD is activated by either TRIM25-mediated ubiquitination (Gack et al. (datexis.com)
  • Hemagglutinins recognize cell-surface glycoconjugates containing sialic acid on the surface of host red blood cells with a low affinity, and use them to enter the endosome of host cells. (wikipedia.org)
  • In contrast, hemagglutinins of bat-derived IAVs target major histocompatibility complex class II (MHC-II) for cell entry. (figshare.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)
  • 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)
  • Hemagglutinins are small proteins that project from the virus membrane surface as 135 Å long spikes with a diameter of 30-50 Å. (wikipedia.org)
  • Note: the free, infectious form of a virus is often termed a "virion," but here, we will use the term "virus" to encompass all stages of the viral life cycle. (rcsb.org)
  • Viral deep sequencing needs an adaptive approach: IRMA, the iterative refinement meta-assembler. (cdc.gov)