Publications by authors named "Paul J Carney"

The globular head domain of influenza virus surface protein hemagglutinin (HA1) is the major target of neutralizing antibodies elicited by vaccines. As little as one amino acid substitution in the HA1 can result in an antigenic drift of influenza viruses, indicating the dominance of some epitopes in the binding of HA to polyclonal serum antibodies. Therefore, identifying dominant binding epitopes of HA is critical for selecting seasonal influenza vaccine viruses.

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Low-pathogenicity avian influenza A(H9N2) viruses, enzootic in poultry populations in Asia, are associated with fewer confirmed human infections but higher rates of seropositivity compared to A(H5) or A(H7) subtype viruses. Cocirculation of A(H5) and A(H7) viruses leads to the generation of reassortant viruses bearing A(H9N2) internal genes with markers of mammalian adaptation, warranting continued surveillance in both avian and human populations. Here, we describe active surveillance efforts in live poultry markets in Vietnam in 2018 and compare representative viruses to G1 and Y280 lineage viruses that have infected humans.

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Of the eighteen hemagglutinin (HA) subtypes (H1-H18) that have been identified in bats and aquatic birds, many HA subtypes have been structurally characterized. However, several subtypes (H8, H11 and H12) still require characterization. To better understand all of these HA subtypes at the molecular level, HA structures from an A(H4N6) (A/swine/Missouri/A01727926/2015), an A(H8N4) (A/turkey/Ontario/6118/1968), an A(H11N9) (A/duck/Memphis/546/1974), an A(H14N5) A/mallard/Gurjev/263/1982, and an A(H15N9) (A/wedge-tailed shearwater/Western Australia/2576/1979 were determined by X-ray crystallography at 2.

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A(H3N2) virus predominated recent influenza seasons, which has resulted in the rigorous investigation of haemagglutinin, but whether neuraminidase (NA) has undergone antigenic change and contributed to the predominance of A(H3N2) virus is unknown. Here, we show that the NA of the circulating A(H3N2) viruses has experienced significant antigenic drift since 2016 compared with the A/Hong Kong/4801/2014 vaccine strain. This antigenic drift was mainly caused by amino acid mutations at NA residues 245, 247 (S245N/S247T; introducing an N-linked glycosylation site at residue 245) and 468.

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Background: Human immunodeficiency virus (HIV)-infected persons are at a higher risk of severe influenza. Although we have shown that a standard-dose intradermal influenza vaccine versus a standard-dose intramuscular influenza vaccine does not result in differences in hemagglutination-inhibition titers in this population, a comprehensive examination of cell-mediated immune responses remains lacking.

Methods: Serological, antigen-specific B-cell, and interleukin 2-, interferon γ-, and tumor necrosis factor α-secreting T-cell responses were assessed in 79 HIV-infected men and 79 HIV-uninfected men.

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The avian influenza A(H7N9) virus continues to cause human infections in China and is a major ongoing public health concern. Five epidemic waves of A(H7N9) infection have occurred since 2013, and the recent fifth epidemic wave saw the emergence of two distinct lineages with elevated numbers of human infection cases and broader geographic distribution of viral diseases compared to the first four epidemic waves. Moreover, highly pathogenic avian influenza (HPAI) A(H7N9) viruses were also isolated during the fifth epidemic wave.

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Unlabelled: During 2013, three new avian influenza A virus subtypes, A(H7N9), A(H6N1), and A(H10N8), resulted in human infections. While the A(H7N9) virus resulted in a significant epidemic in China across 19 provinces and municipalities, both A(H6N1) and A(H10N8) viruses resulted in only a few human infections. This study focuses on the major surface glycoprotein hemagglutinins from both of these novel human viruses.

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A(H1N1)pdm09 influenza A viruses predominated in the 2013-2014 USA influenza season, and although most of these viruses remain sensitive to Food and Drug Administration-approved neuraminidase (NA) inhibitors, alternative therapies are needed. Here we show that monoclonal antibody CD6, selected for binding to the NA of the prototypic A(H1N1)pdm09 virus, A/California/07/2009, protects mice against lethal virus challenge. The crystal structure of NA in complex with CD6 Fab reveals a unique epitope, where the heavy-chain complementarity determining regions (HCDRs) 1 and 2 bind one NA monomer, the light-chain CDR2 binds the neighbouring monomer, whereas HCDR3 interacts with both monomers.

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After their disappearance from the human population in 1968, influenza H2 viruses have continued to circulate in the natural avian reservoir. The isolation of this virus subtype from multiple bird species as well as swine highlights the need to better understand the potential of these viruses to spread and cause disease in humans. Here we analyzed the virulence, transmissibility and receptor-binding preference of two avian influenza H2 viruses (H2N2 and H2N3) and compared them to a swine H2N3 (A/swine/Missouri/2124514/2006 [swMO]), and a human H2N2 (A/England/10/1967 [Eng/67]) virus using the ferret model as a mammalian host.

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A(H3N2) influenza viruses have circulated in humans since 1968, and antigenic drift of the hemagglutinin (HA) protein continues to be a driving force that allows the virus to escape the human immune response. Since the major antigenic sites of the HA overlap into the receptor binding site (RBS) of the molecule, the virus constantly struggles to effectively adapt to host immune responses, without compromising its functionality. Here, we have structurally assessed the evolution of the A(H3N2) virus HA RBS, using an established recombinant expression system.

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Unlabelled: In late 2011, an A(H3N8) influenza virus infection resulted in the deaths of 162 New England harbor seals. Virus sequence analysis and virus receptor binding studies highlighted potential markers responsible for mammalian adaptation and a mixed receptor binding preference (S. J.

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The relative performance of ELISA using globular head domain (GH) and ectodomain hemagglutinins (HAs) as antigens to detect influenza A virus IgG antibody responses was assessed. Assay sensitivity and subtype cross-reactivity were evaluated using sera collected from recipients of monovalent H5N1 vaccine and A(H1N1)pdm09 virus-infected persons. Assay specificity was determined using collections of sera from either individuals unexposed to either H5N1 or A(H1N1)pdm09 viruses or exposed to H5N1 or A(H1N1)pdm09 viruses through vaccination or infection, respectively.

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The novel influenza A(H1N1)pdm09 virus caused an influenza pandemic in 2009. IgM, IgG, and IgA antibody responses to A(H1N1)pdm09 hemagglutinin (HA) following A(H1N1)pdm09 virus infection were analyzed to understand antibody isotype responses. Age-matched control sera collected from U.

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Unlabelled: The noncovalent interactions that mediate trimerization of the influenza hemagglutinin (HA) are important determinants of its biological activities. Recent studies have demonstrated that mutations in the HA trimer interface affect the thermal and pH sensitivities of HA, suggesting a possible impact on vaccine stability (). We used size exclusion chromatography analysis of recombinant HA ectodomain to compare the differences among recombinant trimeric HA proteins from early 2009 pandemic H1N1 viruses, which dissociate to monomers, with those of more recent virus HAs that can be expressed as trimers.

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Propagation of influenza A(H3N2) viruses in MDCK cells has been associated with the emergence of neuraminidase (NA) variants carrying a change at residue 151. In this study, the pyrosequencing assay revealed that ∼90% of A(H3N2) virus isolates analyzed (n=150) contained more than one amino acid variant (D/G/N) at position 151. Susceptibilities of the virus isolates to zanamivir and oseltamivir were assessed using the chemiluminescent and fluorescent NA inhibition (NI) assays.

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Aquatic birds harbor diverse influenza A viruses and are a major viral reservoir in nature. The recent discovery of influenza viruses of a new H17N10 subtype in Central American fruit bats suggests that other New World species may similarly carry divergent influenza viruses. Using consensus degenerate RT-PCR, we identified a novel influenza A virus, designated as H18N11, in a flat-faced fruit bat (Artibeus planirostris) from Peru.

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Antigenic variation among circulating H5N1 highly pathogenic avian influenza A viruses mandates the continuous production of strain-specific pre-pandemic vaccine candidates and represents a significant challenge for pandemic preparedness. Here we assessed the structural, antigenic and receptor-binding properties of three H5N1 HPAI virus hemagglutinins, which were recently selected by the WHO as vaccine candidates [A/Egypt/N03072/2010 (Egypt10, clade 2.2.

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In March 2013, the Chinese Center for Disease Control and Prevention reported human infections with an H7N9 influenza virus, and by 20 July 2013, the numbers of laboratory-confirmed cases had climbed to 134, including 43 fatalities and 127 hospitalizations. The newly emerging H7N9 viruses constitute an obvious public health concern because of the apparent severity of this outbreak. Here we focus on the hemagglutinins (HAs) of these viruses and assess their receptor binding phenotype in relation to previous HAs studied.

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On 29 March 2013, the Chinese Center for Disease Control and Prevention confirmed the first reported case of human infection with an avian influenza A(H7N9) virus. The recent human infections with H7N9 virus, totalling over 130 cases with 39 fatalities to date, have been characterized by severe pulmonary disease and acute respiratory distress syndrome (ARDS). This is concerning because H7 viruses have typically been associated with ocular disease in humans, rather than severe respiratory disease.

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Recently, we reported a unique influenza A virus subtype H17N10 from little yellow-shouldered bats. Its neuraminidase (NA) gene encodes a protein that appears to be highly divergent from all known influenza NAs and was assigned as a new subtype N10. To provide structural and functional insights on the bat H17N10 virus, X-ray structures were determined for N10 NA proteins from influenza A viruses A/little yellow-shouldered bat/Guatemala/164/2009 (GU09-164) in two crystal forms at 1.

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Recurrence of highly pathogenic avian influenza (HPAI) virus subtype H7 in poultry continues to be a public health concern. In 2003, an HPAI H7N7 outbreak in The Netherlands infected 89 people in close contact with affected poultry and resulted in one fatal case. In previous studies, the virus isolated from this fatal case, A/Netherlands/219/2003 (NL219) caused a lethal infection in mouse models and had increased replication efficiency and a broader tissue distribution than nonlethal isolates from the same outbreak.

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Human infections with subtype H7 avian influenza viruses have been reported as early as 1979. In 1996, a genetically stable 24-nucleotide deletion emerged in North American H7 influenza virus hemagglutinins, resulting in an eight amino acid deletion in the receptor-binding site. The continuous circulation of these viruses in live bird markets, as well as its documented ability to infect humans, raises the question of how these viruses achieve structural stability and functionality.

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During the initial pandemic influenza H1N1 virus outbreak, assays such as hemagglutination inhibition and microneutralization provided important information on the relative protection afforded by the population's cross-reactivity from prior infections and immunizations with seasonal vaccines. However, these assays continue to be limited in that they are difficult to automate for high throughput, such as in pandemic situations, as well as to standardize between labs. Thus, new technologies are being sought to improve standardization, reliability, and throughput by using chemically defined reagents rather than whole cells and virions.

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