What are a virus receptors?
A virus receptor can be defined as a host cell surface component recognized by the virus as a gateway to entry into the cell.
How does a virus interact with its host cell?
The interaction between a virus and its host cell begins with attachment of the virus particle to specific receptors on the cell surface.
How important is the attachment step in the identification of virus receptors?
One of the most dynamic areas of virology concerns the identification of virus receptors on host cells. This interest stems in part from the critical importance of the attachment step as a determinant of host species tropism and target cell selection by many viruses.
What are the receptors of viral immunoglobulin?
Common viral receptors include sialylated glycans such as SAs and SA-containing gangliosides, CAMs such as igSF members including CD4, JAM-A, CAR and integrins such as αvβ3, and PtdSer receptors, cell immunoglobulin and mucin domain (TIM), and the Tyro3, Axl, and Mer (TAM) receptors. Virus binding to IgSF members is mediated through the D1 domain.
How do you identify a viral receptor?
The first approach is to identify the receptors by biochemical purification of cellular proteins on the cell surface that bind to the viral antireceptors (ie, viral structural proteins). Affinity purification of plasma membrane proteins using the viral structural proteins as a ligand is feasible.
Do all viruses need receptors?
All viruses need to bind to specific receptor molecules on the surface of target cells to initiate infection. Virus–receptor binding is highly specific, and this specificity determines both the species and the cell type that can be infected by a given virus.
Why do we have viral receptors?
As far as the virus is concerned, the role of its receptor in infection is to provide a point of attachment to a target cell and a signal that it is in an appropriate place to initiate the events leading to fusion with the cell membrane and entry of the virion components into a cell.
How do viruses bind to cells?
Viruses initially stick to cell membranes through interactions unrelated to fusion proteins. The virus surfs along the fluid surface of the cell and eventually the viral fusion proteins bind to receptor molecules on the cell membrane (4).
Do viruses have receptors?
Viral receptors function not only as attachment moieties but also as entry factors, coordinators of viral trafficking, and activators of signaling events, and in many cases, viruses utilize multiple receptors to carry out different functions within the virus life cycle [2].
What is required in order for a virus to replicate?
Viral replication involves six steps: attachment, penetration, uncoating, replication, assembly, and release. During attachment and penetration, the virus attaches itself to a host cell and injects its genetic material into it.
Can viruses recognize cells via proteins and receptors?
Viruses recognize a variety of cell surface molecules specifically, including glycolipids, carbohydrates and proteins with very distinct folding structures. There are viruses specific for a single receptor molecule, whereas others bind to several structurally distinct receptors for host cell entry [2].
Can a virus replicate without a host?
As viruses are obligate intracellular pathogens they cannot replicate without the machinery and metabolism of a host cell.
What is a virus receptor?
A virus receptor can be defined as a host cell surface component recognized by the virus as a gateway to entry into the cell. Ideally, a virus receptor would fulfill three main characteristics: (1) a physical interaction between the virus and the receptor should be demonstrated; (2) occupying the virus-binding site of the receptor (e.g., with an antibody directed against the receptor, should inhibit virus infection); and (3) the cellular sensitivity to virus infection should correlate with receptor expression. Therefore, cells lacking the receptor should not be infected, and transfection with the gene coding for the receptor would confer sensitivity to infection.
What is the main receptor for HIV-1?
The CD4 transmembrane protein expressed by a subset of human T-lymphocytes is widely considered as the main receptor for HIV-1. However, CD4 does not fulfill all the characteristics listed. CD4 interacts with the HIV-1 surface envelope glycoprotein gp120 with high affinity 200,201 and some anti-CD4 antibodies, directed against the gp120 binding site, inhibit HIV-1 infection of CD4 + lymphocytes. 70 The ability of HIV-1 to infect several types of CD4-negative cells, including fibroblasts, 202 neural, 203 and intestinal epithelial cells 204 led to the identification of an alternative receptor for HIV-1, the oligodendrocyte differentiation marker GalCer. 79,80 In this respect, HIV-1 behaved as an atypic retrovirus able to use either a protein (CD4) or a glycolipid (GalCer) to gain entry into various cell types.
What are the affinities of viral vectors?
These affinities mimic classical ligand (virus)/receptor (host cell) interactions, with the ligand composed of a protein moiety embedded in the topology of the viral capsid (e.g., adenovirus, adeno-associated virus (AAV)) or comprising a domain of a glycoprotein embedded in the viral membrane (e.g., Herpes simplex or lentivirus). Receptor binding stimulates endocytosis of the receptor/virus complex by the host cell through the formation of an endosome budding from the cell membrane.
What is the role of the nucleocapsid in the viral genome?
The viral genome needs to get to the nucleus for the virus that replicates in the nucleus. In other words, the viral nucleocapsid has to overcome two barriers (ie, plasma membrane and nuclear membrane). Compare and contrast the mechanisms by which the viruses penetrate the two membranes.
What is a membrane cofactor protein?
Membrane Cofactor Protein (MCP; CD46; measles virus receptor) is a widely expressed regulator of complement activation that serves as a cofactor for the factor I-mediated degradation of C3b and C4b. Discovered a decade ago during an analysis of C3b binding proteins of human peripheral blood mononuclear cells (PBMC) (44) and originally termed gp45–70 to reflect its electrophoretic mobility, it was subsequently shown to possess cofactor activity and renamed to reflect this finding (45). During this same time several groups developed monoclonal antibodies (mAb) to an unknown 60- to 70-kDa protein that subsequently was identified as MCP (46, 47, 48, 49, 50, 51 ).
What is the nACHR?
7.1 Nicotinic acetylcholine receptor. The nAChR was the first rabies virus receptor identified and this receptor is felt to be important for the spread of the virus from the neuromuscular junction at peripheral sites in order to gain access to the CNS along peripheral nerves (Lentz et al., 1982).
What are the key components of virus infection?
Virus receptors are key components of the early events involved in cell infection. The examples outlined above should illustrate that the definition of receptors acting solely as attachment molecules is overly simplistic. In addition to attachment, receptors also actively contribute to entry by initiating conformational changes in the virus that lead to uncoating. In addition, they provide mechanisms for internalization – which increasingly appear to involve signaling events that occur upon receptor binding – in which the virus may subvert a natural receptor cycling process. Furthermore, the identification of virus receptors contributes significantly to our understanding of host, tissue, and cell tropism, and helps explain aspects of virus pathogenesis. The selected bibliography provides further examples illustrating aspects of virus receptor identification and function.
What are the receptors of a virus?
The majority of viral receptors identified to date are cell adhesion molecules (CAMs) that function in cell-to-cell and cell-to-extracellular matrix adhesion and thus are essential mediators of cellular processes such as development, maintenance of cellular structure, cell signaling, and maintenance and repair of tissues [22], [148]. The broad family of CAM includes selectins, cadherins, integrins, and IgSF members [148]. The ubiquitous expression and multifactorial function of CAMs in ligand binding, endocytosis, and signaling provides a plethora of possibilities for viruses to engage CAMs. Viruses including HIV [149], measles virus [150], reovirus [19], rhinovirus [151], adenovirus [20], poliovirus [152], and coxsackievirus B (CVB) [147]utilize IgSF members as receptors. In addition, integrins serve as receptors for reovirus [153], rotavirus [154], [155], adenovirus [156], [157], West Nile virus (WNV) [158], human metapneuomovirus (hMPV) [159], foot-and-mouth disease virus (FMDV) [160], [161], [162], [163], [164], and herpes simplex virus (HSV) [165], as well as human cytomegalovirus HCMV and human herpesvirus-8 [166], [167], [168]. CAMs function to mediate attachment, entry, or signaling or multiple steps that enable viral invasion of the host cell. Interestingly, many of the CAMs are exploited by viruses to sneak their way into tight spaces like the tight junctions [99], [169]. For example, it was recently shown that E-cadherin, a component of the adherens junction, is a receptor for hepatitis C virus, a major cause of chronic liver disease [170]. Discussed below are several examples of viruses that utilize the IgSF members as receptors, demonstrating conservation of similar mechanisms employed by diverse and similar viruses. Overall, the redundancy in receptor usage indicates an evolutionary selection toward particular receptors, which could include common cellular targets, cell surface expression patterns, receptor functionality, or could even suggest that some viruses could have evolved at a time after receptor-binding properties were established.
What are the common viral receptors?
Common viral receptors include sialylated glycans such as SAs and SA-containing gangliosides, CAMs such as igSF members including CD4, JAM-A, CAR and integrins such as αvβ3, and PtdSer receptors, cell immunoglobulin and mucin domain (TIM), and the Tyro3, Axl, and Mer (TAM) receptors. Virus binding to IgSF members is mediated through the D1 domain.
What is IAV in RNA?
IAV is a segmented single-stranded RNA (− ssRNA) virus encased in a lipid envelope with glycoproteins hemagglutinin (HA) and neuraminidase (NA) that extend away from the surface of the virion envelope [49]. HA confers binding to SA receptors, while NA is necessary for viral release from sialyl linkages on host cells during viral budding [50]. Following SA binding, IAV enters cells by receptor-dependent endocytosis [51]or marcopinocytosis [52]and HA mediates fusion of the viral membrane with endosomal membranes [53]. It has recently become clear that binding to SA receptors alone is not sufficient to mediate entry, and rather IAV entry is facilitated by C-type lectin receptors (CLRs), dendritic cell-specific intercellular adhesion molecular 3-grabbing non-integrin (DC-SIGN or CD209), and L-SIGN (CD209L) [51]. The complexity in understanding the HA-SA interactions is complicated by the mere number of hosts that are susceptible to IAV including humans, bats, and avian and swine species [37], [54], [55]. There is further complexity in variation due to at least 18 HA and 11 NA subtypes and the potential for viral gene segment mixing due to reassortment [37]. Like many other viral attachment proteins, HA and NA are antigenic sites subject to host immune pressures that can be neutralized by antibodies [56]. IAV high mutation rates allows for amino acid changes in HA, which can result in host immune evasion, but also results in antigenic drift, while reassortment of viral gene segments in a reassortment reservoir can result in antigenic shift [57]. Reassortment and antigenic drift are responsible for the widespread epidemics and pandemics that arise due to host immune evasion [54].
Why do viruses have multiple receptors?
Many viruses engage one or multiple specific receptors in order to carry out attachment, entry, and/or signaling [1]. A single virus receptor can carry out one or more of the aforementioned functions or viruses can utilize distinct receptors to mediate each function, thereby lending even greater specificity in tissue tropism. In other cases, a coordination of viral–receptor interactions is necessary to mediate specific functions such as activation of signaling events [1], [144], [147]. Interactions with multiple receptors also provide an extra layer of security to ensure that the virus is targeting an appropriate target cell for infection such as a door having a deadbolt in addition to the doorknob lock. Studies of viral receptors have revealed unique receptors but mostly common receptors that can be categorized as CAMs including integrins, selectins, cadherins, and immunoglobulin superfamily (IgSF) receptors [22]. Recently, PtdSer receptors have been identified as receptors for a range of enveloped viruses [25]. The redundancy in viral receptor usage thus reveals potential evolutionary conservation and suggests that viruses have evolved to utilize particular receptors that convey necessary steps to drive the infectious process within host cells. Furthermore, this redundancy could serve as the platform for broad-spectrum antiviral therapies to inhibit viral infection from a range of viruses. Discussed below are examples of virus utilization of common viral receptors to drive the infectious cycle.
Where is PTDSer expressed?
PtdSer is normally expressed on the inner leaflet of the plasma membrane of living cells. However, PtdSer becomes exposed in necrotic or apoptotic cells, and the exposure of PtdSer allows for phagocytic cells to recognize and remove dead cells [25], [211]. PtdSer binding to the PtdSer receptors can occur either through a direct interaction or through a ligand that binds directly to PtdSer and the receptor, acting as a bridge [23], [24]. PtdSer receptors that enhance virus entry have been termed PtdSer-mediated virus entry enhancing receptors PVEERs [25]. Enveloped viruses with PtdSer expressed on the viral envelope appear like apoptotic bodies and can be recognized by PVEERS and “trick” the cell into to engulfing it through phagocytosis; the usage of cell clearance mechanisms to invade cells has been likened to apoptotic mimicry [25]. As enveloped viruses bud from host cells and pinch off a portion of the plasma membrane, where the PtdSer is located on the inner leaflet, it begs the question: how does the membrane get flipped inside out so that the PtdSer can be surface expressed on the virion envelope? An interesting new finding suggests that EBOV, which has been demonstrated to utilize the TIM-1 and TAM receptor AXL [205], [212], [213]requires the XK-related protein (Xkr) 8 scramblase to expose the PtdSer and disguise the virus as an apoptotic cell [214]. In fact, the Xkr8 traffics with EBOV to sites of budding and gets incorporated into EBOV virus-like particles, and thereby enhances EBOV entry in a PtdSer-dependent manner [214]. However, it should be noted that the presence of PtdSer alone is not sufficient for enveloped viral entry by apoptotic mimicry, as entry of viruses with PtdSer-expressing envelopes including IAV, vesicular stomatitis virus, and coronaviruses is not enhanced by PVEERS [25]. Thus, while a growing number of enveloped viruses utilize a common mechanism to enter cells through PtdSer receptors, the presence of the viral glycoprotein and cell type-dependent differences influence this process [25].
What is the role of a virus in a cell?
Viruses utilize elegant strategies to attach to one or multiple receptors, overcome the plasma membrane barrier, enter, and access the necessary host cell machinery.
What receptors are used to mediate viral attachment?
The utilization of a SA receptor is not unique among coronaviruses, as other beta-CoVs utilize SA-containing receptors to mediate entry [102], [103], [104], [105], while other CoVs bind to SA to mediate viral attachment and utilize a separate entry receptor [89], [106], [107]. However, the strategy utilized to define the MERS-CoV-SA interaction was an elegant example of creative molecular biology and biochemistry. Li et al. [35]utilized a Lumazine synthaseprotein of Aquifex aeolicusbacterium that was able to self assemble into an icosahedral nanoparticle, which was then used as the core for expression of Fc-tagged MERS-CoV S1 protein S1Adomain. The nanoparticles were then utilized for functional studies and for glycan array screening, through which α2,3-linked SAs were found to be the preferred sialoglycans [35]. Sialoglycan receptors serve to mediate MERS-CoV attachment specifically, and removal of SA results in significantly reduced infection in human airway epithelial cells. In addition, expression of α2,3-linked sialoglycans correlates with sites of MERS-CoV replication including the nasal epithelium of dromedary camels and alveoli of human lung [35]. Purification and expression of viral attachment proteins thus allows for specified study of direct interactions of presumed low-affinity binding events. Further fine-tuning can be employed to define the precise interactions biochemically, which can then be confirmed through additional functional studies. This important finding that MERS-CoV engages a SA receptor in addition to DPP4 [35]provides a broader understanding of the host cell factors required for host cell invasion and highlights new information regarding cell surface structures shared among coronavirus host species that could enable host jump and infection.
What is the role of virus receptors in the host cell?
Virus-receptor interactions play a key regulatory role in viral host range, tissue tropism, and viral pathogenesis. Viruses utilize elegant strategies to attach to one or multiple receptors, overcome the plasma membrane barrier, enter, and access the necessary host cell machinery. The viral attachme …
Why is redundancy important in viral receptor usage?
The redundancy in receptor usage suggests that viruses target particular receptors or "common locks" to take advantage of their cellular function and also suggests evolutionary conservation. Due to the importance of initial virus interactions with host cells in viral pathogenesis and the redundancy in viral receptor usage, ...
How do viruses interact with their host cells?
The viral attachment protein can be viewed as the "key" that unlocks host cells by interacting with the "lock"-the receptor-on the cell surface , and these lock-and-key interactions are critical for viruses to successfully invade host cells. Many common themes have emerged in virus-receptor utilization within and across virus families demonstrating that viruses often target particular classes of molecules in order to mediate these events. Common viral receptors include sialylated glycans, cell adhesion molecules such as immunoglobulin superfamily members and integrins, and phosphatidylserine receptors. The redundancy in receptor usage suggests that viruses target particular receptors or "common locks" to take advantage of their cellular function and also suggests evolutionary conservation. Due to the importance of initial virus interactions with host cells in viral pathogenesis and the redundancy in viral receptor usage, exploitation of these strategies would be an attractive target for new antiviral therapeutics.
What is the key to a virus?
The viral attachment protein can be viewed as the "key" that unlocks host cells by interacting with the "lock"-the receptor-on the cell surface, and these lock-and-key interactions are critical for viruses to successfully invade host cells.
What is the key to cellular invasion?
Virus-Receptor Interactions: The Key to Cellular Invasion
What is a viral receptor?from sciencedirect.com
Viral receptors are naturally occurring cellular molecules that serve physiological functions for the cell—functions that have nothing to do with infection. From: Viral Pathogenesis (Third Edition), 2016. Download as PDF. About this page.
What is the main receptor for HIV-1?from sciencedirect.com
The CD4 transmembrane protein expressed by a subset of human T-lymphocytes is widely considered as the main receptor for HIV-1. However, CD4 does not fulfill all the characteristics listed. CD4 interacts with the HIV-1 surface envelope glycoprotein gp120 with high affinity 200,201 and some anti-CD4 antibodies, directed against the gp120 binding site, inhibit HIV-1 infection of CD4 + lymphocytes. 70 The ability of HIV-1 to infect several types of CD4-negative cells, including fibroblasts, 202 neural, 203 and intestinal epithelial cells 204 led to the identification of an alternative receptor for HIV-1, the oligodendrocyte differentiation marker GalCer. 79,80 In this respect, HIV-1 behaved as an atypic retrovirus able to use either a protein (CD4) or a glycolipid (GalCer) to gain entry into various cell types.
What is the pre-S domain of DHBV?from sciencedirect.com
The pre-S domain of DHBV large envelope protein is believed to be the ligand for the viral receptor ( Ishikawa and Ganem, 1995; Klingmuller and Schaller, 1993; Summers et al., 1991 ).
What is the role of Pol in HBV?from sciencedirect.com
The fact that the HBV Pol protein plays multiple critical functions in viral assembly and replication has catalyzed intense efforts to develop anti-HBV drugs ( Feld et al., 2003 ). Due to challenges in getting appropriate amounts of soluble protein for identifying crystal structure, structural an analysis of Pol is difficult ( Nassal, 2008 ). As a result, genetic analysis is an alternative method to get structural information about HBV Pol. SP subdomain seems to have a novel structural role. Cysteine residues in HBV Pol coordinate linking with zinc ion. This represents a novel feature of hepadnaviral Pol in comparison to retroviral RT. The zinc-finger motif presents a novel antiviral target for therapeutic invention against HBV-induced disease.
What kinase converts acyclovir to acyclovir monophosphate?from sciencedirect.com
The viral thymidine kinase converts acyclovir to acyclovir monophosphate. Next, the cellular pyrimidine kinase converts the monophosphate into acyclovir triphosphate. Acyclovir triphosphate, which lacks the ribose ring, acts as chain terminator for the viral DNA replication.
What is the target of the release of virions from infected cells?from sciencedirect.com
Release: Budding or the release of virions from infected cells can be antiviral targets. Blockade of the virions released from the infected cells by drugs is an effective strategy to stop viral spread to surrounding cells. Oseltamivir, an antiinfluenza drug, blocks the viral release from the infected cells (see Table 26.1 ). The NA protein (ie, neuraminidase) of influenza virus, an envelope glycoprotein, facilitates the virion release from cells by cleaving the sialic acid on the plasma membrane of infected cells (see Box 15.1 and Fig. 26.12 ).
What is the role of car in the immune system?from sciencedirect.com
Concomitantly with its role as a viral receptor, CAR can also regulate intracellular pathways regulating the immune response without being engaged by viral ligands. For instance, CAR interacts with JAM-L, providing signals for neutrophil transepithelial migration (Zen et al., 2005) ( Figs. 3-i and 7). Like other T cells, epithelial γδ T cells need coreceptor engagement and costimulation for a proper antigen response. γδ T cells express JAM-L at their surface that is responsible for signal transduction. This is leading to cell activation and proliferation upon engagement with CAR, which is found on epithelial cells (Fig. 3 -i). This interaction is mediated by the CAR D1 domain with the membrane proximal Ig domain of JAM-L ( Zen et al., 2005). Soluble CAR is able to bind to JAM-L and induces proliferation and cytokine production by epithelial T cells, in a JAM-L-dependent manner (Witherden et al., 2010). This interaction triggers epithelial γδ T-cell activation, supplying a rapid response to environmental insults (Verdino et al., 2010 ). This epithelial γδ T-cell activation requires PI3K recruitment to JAM-L ICD that will activate downstream effectors for signal transduction ( Verdino et al., 2010; Witherden et al., 2010 ).
What is a viral receptor?from sciencedirect.com
Viral receptors are naturally occurring cellular molecules that serve physiological functions for the cell—functions that have nothing to do with infection. From: Viral Pathogenesis (Third Edition), 2016. Download as PDF. About this page.
What is the main receptor for HIV-1?from sciencedirect.com
The CD4 transmembrane protein expressed by a subset of human T-lymphocytes is widely considered as the main receptor for HIV-1. However, CD4 does not fulfill all the characteristics listed. CD4 interacts with the HIV-1 surface envelope glycoprotein gp120 with high affinity 200,201 and some anti-CD4 antibodies, directed against the gp120 binding site, inhibit HIV-1 infection of CD4 + lymphocytes. 70 The ability of HIV-1 to infect several types of CD4-negative cells, including fibroblasts, 202 neural, 203 and intestinal epithelial cells 204 led to the identification of an alternative receptor for HIV-1, the oligodendrocyte differentiation marker GalCer. 79,80 In this respect, HIV-1 behaved as an atypic retrovirus able to use either a protein (CD4) or a glycolipid (GalCer) to gain entry into various cell types.
What is the pre-S domain of DHBV?from sciencedirect.com
The pre-S domain of DHBV large envelope protein is believed to be the ligand for the viral receptor ( Ishikawa and Ganem, 1995; Klingmuller and Schaller, 1993; Summers et al., 1991 ).
What is the role of Pol in HBV?from sciencedirect.com
The fact that the HBV Pol protein plays multiple critical functions in viral assembly and replication has catalyzed intense efforts to develop anti-HBV drugs ( Feld et al., 2003 ). Due to challenges in getting appropriate amounts of soluble protein for identifying crystal structure, structural an analysis of Pol is difficult ( Nassal, 2008 ). As a result, genetic analysis is an alternative method to get structural information about HBV Pol. SP subdomain seems to have a novel structural role. Cysteine residues in HBV Pol coordinate linking with zinc ion. This represents a novel feature of hepadnaviral Pol in comparison to retroviral RT. The zinc-finger motif presents a novel antiviral target for therapeutic invention against HBV-induced disease.
What kinase converts acyclovir to acyclovir monophosphate?from sciencedirect.com
The viral thymidine kinase converts acyclovir to acyclovir monophosphate. Next, the cellular pyrimidine kinase converts the monophosphate into acyclovir triphosphate. Acyclovir triphosphate, which lacks the ribose ring, acts as chain terminator for the viral DNA replication.
What is the target of the release of virions from infected cells?from sciencedirect.com
Release: Budding or the release of virions from infected cells can be antiviral targets. Blockade of the virions released from the infected cells by drugs is an effective strategy to stop viral spread to surrounding cells. Oseltamivir, an antiinfluenza drug, blocks the viral release from the infected cells (see Table 26.1 ). The NA protein (ie, neuraminidase) of influenza virus, an envelope glycoprotein, facilitates the virion release from cells by cleaving the sialic acid on the plasma membrane of infected cells (see Box 15.1 and Fig. 26.12 ).
What is the role of car in the immune system?from sciencedirect.com
Concomitantly with its role as a viral receptor, CAR can also regulate intracellular pathways regulating the immune response without being engaged by viral ligands. For instance, CAR interacts with JAM-L, providing signals for neutrophil transepithelial migration (Zen et al., 2005) ( Figs. 3-i and 7). Like other T cells, epithelial γδ T cells need coreceptor engagement and costimulation for a proper antigen response. γδ T cells express JAM-L at their surface that is responsible for signal transduction. This is leading to cell activation and proliferation upon engagement with CAR, which is found on epithelial cells (Fig. 3 -i). This interaction is mediated by the CAR D1 domain with the membrane proximal Ig domain of JAM-L ( Zen et al., 2005). Soluble CAR is able to bind to JAM-L and induces proliferation and cytokine production by epithelial T cells, in a JAM-L-dependent manner (Witherden et al., 2010). This interaction triggers epithelial γδ T-cell activation, supplying a rapid response to environmental insults (Verdino et al., 2010 ). This epithelial γδ T-cell activation requires PI3K recruitment to JAM-L ICD that will activate downstream effectors for signal transduction ( Verdino et al., 2010; Witherden et al., 2010 ).
Why is receptor specificity important?from pubmed.ncbi.nlm.nih.gov
Therefore, receptor specificity plays an important role in the viral cell and tissue tropism, interspecies transmission and adaptation to a new host, and a poor fit of avian viruses to receptors in humans limits the emergence of new pandemic strains. Adaptation of an avian virus to a mammalian host also involves enhanced activity ...
What are the determinants of the H5N1 virus?from pubmed.ncbi.nlm.nih.gov
Important determinants for virus infection are epithelial cell receptors identified as gl …
