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1.
BMC Public Health ; 23(1): 1991, 2023 10 12.
Article in English | MEDLINE | ID: mdl-37828476

ABSTRACT

BACKGROUND: This study sought to evaluate the risk factors behind developing psychological problems as per specific mental health assessment instruments. This study focuses specifically on frontline healthcare professionals of the COVID-19 pandemic era, and evaluated the psychological assessment of frontline healthcare professionals. METHODS: Studies reporting on the psychological assessment of frontline healthcare professionals were retrieved from the PubMed, Embase, Web of Science, Ovid, EBSCO, and Cochrane Library databases. The recommended method was used to assess the risk of bias of the included studies. The random-effects method was applied when significant heterogeneity was observed. RESULTS: The combined results from the 20 included articles indicated that frontline healthcare professionals had a higher risk of developing anxiety in comparison with non-frontline healthcare workers, with similar levels of depression scoring were observed. Healthcare providers aged > 40 years had a lower probability of developing anxiety and seemed to experience minimal depression. Conversely, frontline workers had a higher incidence of anxiety than that of depression. Being single (not in a relationship) could influence the PHQ-9 scores instead of those concerning the GAD-7. The gender gap was not proven to be significantly wide between healthcare professionals with or without anxiety; however, being male was proven to be positively correlated with depression. CONCLUSION: In general, the risk factors for susceptibility to psychological problems among frontline healthcare professionals during the COVID-19 pandemic concerned those of a lower age, being single, being male, and being engage in frontline healthcare work.


Subject(s)
COVID-19 , Humans , Male , Female , COVID-19/epidemiology , SARS-CoV-2 , Pandemics , Depression/psychology , Health Personnel/psychology , Anxiety/psychology , Risk Factors , Delivery of Health Care
2.
Vaccine ; 41(29): 4302-4312, 2023 06 29.
Article in English | MEDLINE | ID: mdl-37301705

ABSTRACT

Most seasonal influenza vaccines are produced using hemagglutinin (HA) surface antigens from inactivated virions. However, virions are thought to be a suboptimal source for the less abundant neuraminidase (NA) surface antigen, which is also protective against severe disease. Here, we demonstrate that inactivated influenza virions are compatible with two modern approaches for improving protective antibody responses against NA. Using a DBA/2J mouse model, we show that the strong infection-induced NA inhibitory (NAI) antibody responses are only achieved by high dose immunizations of inactivated virions, likely due to the low viral NA content. Based on this observation, we first produced virions with higher NA content by using reverse genetics to exchange the viral internal gene segments. Single immunizations with these inactivated virions showed enhanced NAI antibody responses and improved NA-based protection from a lethal viral challenge while also allowing for the development of natural immunity to the heterotypic challenge virus HA. Second, we combined inactivated virions with recombinant NA protein antigens. These combination vaccines increased NA-based protection following viral challenge and elicited stronger antibody responses against NA than either component alone, especially when the NAs possessed similar antigenicity. Together, these results indicate that inactivated virions are a flexible platform that can be easily combined with protein-based vaccines to improve protective antibody responses against influenza antigens.


Subject(s)
Influenza Vaccines , Influenza, Human , Orthomyxoviridae Infections , Animals , Mice , Humans , Neuraminidase , Antibody Formation , Antibodies, Viral , Mice, Inbred DBA , Recombinant Proteins , Hemagglutinin Glycoproteins, Influenza Virus
3.
J Biol Chem ; 299(2): 102891, 2023 02.
Article in English | MEDLINE | ID: mdl-36634846

ABSTRACT

Influenza A viruses and the bacterium Streptococcus pneumoniae (pneumococci) both express neuraminidases that catalyze release of sialic acid residues from oligosaccharides and glycoproteins. Although these respiratory pathogen neuraminidases function in a similar environment, it remains unclear if these enzymes use similar mechanisms for sialic acid cleavage. Here, we compared the enzymatic properties of neuraminidases from two influenza A subtypes (N1 and N2) and the pneumococcal strain TIGR4 (NanA, NanB, and NanC). Insect cell-produced N1 and N2 tetramers exhibited calcium-dependent activities and stabilities that varied with pH. In contrast, E. coli-produced NanA, NanB, and NanC were isolated as calcium insensitive monomers with stabilities that were more resistant to pH changes. Using a synthetic substrate (MUNANA), all neuraminidases showed similar pH optimums (pH 6-7) that were primarily defined by changes in catalytic rate rather than substrate binding affinity. Upon using a multivalent substrate (fetuin sialoglycans), much higher specific activities were observed for pneumococcal neuraminidases that contain an additional lectin domain. In virions, N1 and especially N2 also showed enhanced specific activity toward fetuin that was lost upon the addition of detergent, indicating the sialic acid-binding capacity of neighboring hemagglutinin molecules likely contributes to catalysis of natural multivalent substrates. These results demonstrate that influenza and pneumococcal neuraminidases have evolved similar yet distinct strategies to optimize their catalytic activity.


Subject(s)
Influenza A virus , N-Acetylneuraminic Acid , Neuraminidase , Calcium/metabolism , Catalysis , Escherichia coli/enzymology , N-Acetylneuraminic Acid/metabolism , Neuraminidase/metabolism , Streptococcus pneumoniae/enzymology , Influenza A virus/enzymology , Animals , Cell Line
4.
Nat Commun ; 13(1): 7864, 2022 12 21.
Article in English | MEDLINE | ID: mdl-36543789

ABSTRACT

Contemporary influenza A H3N2 viruses circulating since 2016 have acquired a glycosylation site in the neuraminidase in close proximity to the enzymatic active site. Here, we investigate if this S245N glycosylation site, as a result of antigenic evolution, can impact binding and function of human monoclonal antibodies that target the conserved active site. While we find that a reduction in the inhibitory ability of neuraminidase active site binders is measurable, this class of broadly reactive monoclonal antibodies maintains protective efficacy in vivo.


Subject(s)
Antibodies, Monoclonal , Influenza A Virus, H3N2 Subtype , Neuraminidase , Humans , Antibodies, Monoclonal/chemistry , Antibodies, Monoclonal/immunology , Antibodies, Viral/chemistry , Antibodies, Viral/metabolism , Catalytic Domain/immunology , Catalytic Domain/physiology , Glycosylation , Hemagglutinin Glycoproteins, Influenza Virus , Influenza A virus , Influenza A Virus, H3N2 Subtype/immunology , Influenza A Virus, H3N2 Subtype/metabolism , Influenza, Human/immunology , Influenza, Human/metabolism , Neuraminidase/chemistry , Neuraminidase/immunology
5.
NPJ Vaccines ; 7(1): 79, 2022 Jul 14.
Article in English | MEDLINE | ID: mdl-35835790

ABSTRACT

Although viral-based influenza vaccines contain neuraminidase (NA or N) antigens from the recommended seasonal strains, NA is not extensively evaluated like hemagglutinin (H) during the strain selection process. Here, we compared the antigenicity of NAs from recently recommended H1N1 (2010-2021 seasons) and H3N2 (2015-2021 seasons) vaccine strains and viruses that circulated between September 2019 and December 2020. The antigenicity was evaluated by measuring NA ferret antisera titers that provide 50% inhibition of NA activity in an enzyme-linked lectin assay. Our results show that NAs from circulating H1N1 viruses and vaccine strains for the 2017-2021 seasons are all antigenically similar and distinct from the NA in the H1N1 strain recommended for the 2010-2017 seasons. Changes in N1 antigenicity were attributed to the accumulation of substitutions over time, especially the loss of an N-linked glycosylation site (Asn386) in current N1s. The NAs from circulating H3N2 viruses and the 2020-2021 vaccine strains showed similar antigenicity that varied across the N2s in the 2016-2020 vaccine strains and was distinct from the N2 in the 2015-2016 vaccine strain. These data suggest that the recent N1 antigenicity has remained similar since the loss of the head domain N-linked glycosylation site, whereas N2 antigenicity has changed more incrementally each season.

6.
J Virol ; 95(24): e0116021, 2021 11 23.
Article in English | MEDLINE | ID: mdl-34613807

ABSTRACT

Supplementing influenza vaccines with recombinant neuraminidase (rNA) antigens remains a promising approach for improving suboptimal vaccine efficacy. However, correlations among rNA designs, properties, and protection have not been systematically investigated. Here, we performed a comparative analysis of several rNAs produced by the baculovirus/insect cell system. The rNAs were designed with different tetramerization motifs and NA domains from a recent H1N1 vaccine strain (A/Brisbane/02/2018) and compared for enzymatic properties, antigenicity, stability, and protection in mice. We found that the enzymatic properties differ between rNAs containing the NA head domain versus the full ectodomain, the formation of higher-order rNA oligomers is tetramerization domain dependent, whereas the protective efficacy is more contingent on the combination of the tetramerization and NA domains. Following single-dose immunizations, an rNA possessing the full ectodomain and the tetramerization motif from the human vasodilator-stimulated phosphoprotein provided much better protection than an rNA with ∼10-fold more enzymatically active molecules that is comprised of the head domain and the same tetramerization motif. In contrast, these two rNA designs provided comparable protection when the tetramerization motif from the tetrabrachion protein was used instead. These findings demonstrate that individual rNAs should be thoroughly evaluated for vaccine development, as the heterologous domain combination can result in rNAs with similar key attributes that vastly differ in protection. IMPORTANCE For several decades, it has been proposed that influenza vaccines could be supplemented with recombinant neuraminidase (rNA) to improve efficacy. However, some key questions for manufacturing stable and immunogenic rNAs remain to be answered. We show here that the tetramerization motifs and NA domains included in the rNA construct design can have a profound impact on the biochemical, immunogenic, and protective properties. We also show that the single-dose immunization regimen is more informative for assessing the rNA immune response and protective efficacy, which is surprisingly more dependent on the specific combination of NA and tetramerization domains than common attributes for evaluating NA. Our findings may help to optimize the design of rNAs that can be used to improve or develop influenza vaccines.


Subject(s)
Antibodies, Viral/blood , Influenza A Virus, H1N1 Subtype/enzymology , Influenza A Virus, H1N1 Subtype/genetics , Influenza Vaccines/immunology , Neuraminidase/genetics , Orthomyxoviridae Infections/prevention & control , Animals , Antibodies, Viral/immunology , Baculoviridae/genetics , Baculoviridae/metabolism , Cross Protection , Female , Humans , Influenza A Virus, H5N1 Subtype/genetics , Influenza A Virus, H5N1 Subtype/immunology , Influenza, Human/immunology , Mice , Mice, Inbred DBA , Neuraminidase/immunology , Vaccination , Vaccine Development , Vaccine Efficacy
7.
PLoS Pathog ; 17(4): e1009171, 2021 04.
Article in English | MEDLINE | ID: mdl-33872324

ABSTRACT

Virions are a common antigen source for many viral vaccines. One limitation to using virions is that the antigen abundance is determined by the content of each protein in the virus. This caveat especially applies to viral-based influenza vaccines where the low abundance of the neuraminidase (NA) surface antigen remains a bottleneck for improving the NA antibody response. Our systematic analysis using recent H1N1 vaccine antigens demonstrates that the NA to hemagglutinin (HA) ratio in virions can be improved by exchanging the viral backbone internal genes, especially the segment encoding the polymerase PB1 subunit. The purified inactivated virions with higher NA content show a more spherical morphology, a shift in the balance between the HA receptor binding and NA receptor release functions, and induce a better NA inhibitory antibody response in mice. These results indicate that influenza viruses support a range of ratios for a given NA and HA pair which can be used to produce viral-based influenza vaccines with higher NA content that can elicit more balanced neutralizing antibody responses to NA and HA.


Subject(s)
Antibodies, Viral/immunology , Hemagglutinins/immunology , Influenza Vaccines/immunology , Influenza, Human/virology , Neuraminidase/genetics , Animals , Antibodies, Neutralizing/blood , Cowpox virus/immunology , Hemagglutinin Glycoproteins, Influenza Virus/immunology , Humans , Influenza A Virus, H1N1 Subtype/immunology , Mice
8.
Viruses ; 12(6)2020 05 30.
Article in English | MEDLINE | ID: mdl-32486222

ABSTRACT

Influenza virus infection elicits antibodies against the receptor-binding protein hemagglutinin (HA) and the receptor-cleaving protein neuraminidase (NA). Because HA is essential for viral entry, antibodies targeting HA often potently neutralize the virus in single-cycle infection assays. However, antibodies against NA are not potently neutralizing in such assays, since NA is dispensable for single-cycle infection. Here we show that a modified influenza virus that depends on NA for receptor binding is much more sensitive than a virus with receptor-binding HA to neutralization by some anti-NA antibodies. Specifically, a virus with a receptor-binding G147R N1 NA and a binding-deficient HA is completely neutralized in single-cycle infections by an antibody that binds near the NA active site. Infection is also substantially inhibited by antibodies that bind NA epitopes distant from the active site. Finally, we demonstrate that this modified virus can be used to efficiently select mutations in NA that escape antibody binding, a task that can be laborious with typical influenza viruses that are not well neutralized by anti-NA antibodies. Thus, viruses dependent on NA for receptor binding allow for sensitive in vitro detection of antibodies binding near the catalytic site of NA and enable the selection of viral escape mutants.


Subject(s)
Antibodies, Neutralizing/metabolism , Antibodies, Viral/metabolism , Neuraminidase/metabolism , Orthomyxoviridae/metabolism , Receptors, Virus/metabolism , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , Epitopes/immunology , Humans , Influenza A Virus, H1N1 Subtype/genetics , Influenza A Virus, H1N1 Subtype/immunology , Influenza A Virus, H1N1 Subtype/metabolism , Influenza, Human/immunology , Influenza, Human/virology , Neutralization Tests , Orthomyxoviridae/genetics , Orthomyxoviridae/immunology , RNA, Viral/genetics , Sequence Analysis, RNA
9.
Asian J Psychiatr ; 51: 101983, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32146142

ABSTRACT

Some evidence pointed out that Electro-Convulsive Treatment (ECT) could increase the level of brain-derived neurotrophic factor (BDNF) in depressive patients. However, there are some disagreements. The purpose of the study is through a systematic review and meta-analysis to evaluate BDNF levels after ECT in patients with Major depressive disorder. Two independent researchers searched of published articles in the databases of Cochrane Library, PubMed, MEDLINE, EMBASE and WanFang Data, from January 1990 to March 2019. The following key words were used: "depression" or "depressive disorder", "major depressive disorder", "unipolar depression", "brain-derived neurotrophic factor" or "BDNF", and "electroconvulsive" or "ECT". A total of 22 studies met the inclusion criteria of the meta-analysis and included into our analysis. BDNF levels were increased among patients with MDD after ECT (P = 0.000) in plasma samples. The standardized mean difference (SMD) was 0.695 (95 % CI: 0.402-0.988). We also found BDNF levels increased on one week and one month after finishing ECT (SMD = 0.491, 95 %CI: 0.150,0.833, P = 0.005; and SMD = 0.812, 95 %CI: 0.326,1.298, P = 0.001, respectively). Our findings suggest that BDNF levels may increase after ECT and may possibly be used as an indicator of treatment response after one or more weeks of ECT in patients with depression. However, additional investigation of BDNF levels with different ECT durations are needed in responders and non-responders.


Subject(s)
Brain-Derived Neurotrophic Factor , Depressive Disorder, Major , Electroconvulsive Therapy , Databases, Factual , Depressive Disorder, Major/therapy , Dissent and Disputes , Humans
10.
PLoS One ; 14(9): e0222436, 2019.
Article in English | MEDLINE | ID: mdl-31513662

ABSTRACT

Vaccines that elicit broadly cross-neutralizing antibodies, including antibodies that target the conserved stem of hemagglutinin (HA), are being developed as a strategy for next-generation influenza vaccines that protect against influenza across multiple years. However, efficient induction of cross-neutralizing antibodies remains a challenge, and potential escape mutations have not been well characterized. Here we elicited cross-neutralizing antibodies by immunizing animals with the hemagglutinins from H5 and H9 subtype influenza A viruses that are sensitive to neutralization by stem antibodies. We further isolated and characterized an HA stem monoclonal antibody 4C2 that broadly neutralizes group 1 influenza viruses and identified HA mutations that reduced sensitivity to stem antibodies. Our results offer insights for next-generation influenza vaccine strategies for inducing cross-neutralizing antibodies.


Subject(s)
Antibodies, Monoclonal/immunology , Hemagglutinin Glycoproteins, Influenza Virus/immunology , Influenza Vaccines/immunology , Animals , Antibodies, Monoclonal/isolation & purification , Antibodies, Monoclonal/metabolism , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , HEK293 Cells , Hemagglutinin Glycoproteins, Influenza Virus/metabolism , Hemagglutinins , Humans , Influenza A Virus, H5N1 Subtype/immunology , Influenza A virus/immunology , Influenza, Human/prevention & control , Mice , Neutralization Tests , Orthomyxoviridae Infections/immunology
11.
Int J Mol Med ; 44(4): 1205-1218, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31432094

ABSTRACT

Neuropathic pain (NP) is a complex, chronic pain condition caused by injury or dysfunction affecting the somatosensory nervous system. This study aimed to identify crucial genes and miRNAs involved in NP. Microarray data (access number GSE91396) were downloaded from the Gene Expression Omnibus (GEO). Murine RNA­seq samples from three brain regions [nucleus accumbens, (NAc); medial prefrontal cortex, (mPFC) and periaqueductal gray, (PAG)]were compared between the spared nerve injury (SNI) model and a sham surgery. After data normalization, differentially expressed RNAs were screened using the limma package and functional enrichment analysis was performed with Database for Annotation, Visualization and Integrated Discovery. The microRNA (miRNA/miR)­mRNA regulatory network and miRNA­target gene­pathway regulatory network were constructed using Cytoscape software. A total of 2,776 differentially expressed RNAs (219 miRNAs and 2,557 mRNAs) were identified in the SNI model compared with the sham surgery group. A total of two important modules (red and turquoise module) were found to be related to NP using weighed gene co­expression network analysis (WGCNA) for the 2,325 common differentially expressed RNAs in three brain regions. The differentially expressed genes (DEGs) in the miRNA­mRNA regulatory network were significantly enriched in 21 Gene Ontology terms and five pathways. A total of four important DEGs (CXCR2, IL12B, TNFSF8 and GRK1) and five miRNAs (miR­208a­5p, miR­7688­3p, miR­344f­3p, miR­135b­3p and miR­135a­2­3p) were revealed according to the miRNA­target gene­pathway regulatory network to be related to NP. Four important DEGs (CXCR2, IL12B, TNFSF8 and GRK1) and five miRNAs (miR­208a­5p, miR­7688­3p, miR­344f­3p, miR­135b­3p and miR­135a­2­3p) were differentially expressed in SNI, indicating their plausible roles in NP pathogenesis.


Subject(s)
Gene Expression , MicroRNAs/genetics , Neuralgia/etiology , Animals , Computational Biology/methods , Databases, Genetic , Disease Models, Animal , Disease Progression , Gene Expression Profiling , Gene Expression Regulation , Gene Ontology , Gene Regulatory Networks , Male , Mice , Neuralgia/drug therapy , Neuralgia/metabolism , Neuralgia/physiopathology , RNA, Messenger/genetics , Signal Transduction
12.
Nat Microbiol ; 4(12): 2216-2225, 2019 12.
Article in English | MEDLINE | ID: mdl-31406333

ABSTRACT

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. As a result, the binding of the NA of A(H3N2) virus by some human monoclonal antibodies, including those that have broad reactivity to the NA of the 1957 A(H2N2) and 1968 A(H3N2) reference pandemic viruses as well as contemporary A(H3N2) strains, was reduced or abolished. This antigenic drift also reduced NA-antibody-based protection against in vivo virus challenge. X-ray crystallography showed that the glycosylation site at residue 245 is within a conserved epitope that overlaps the NA active site, explaining why it impacts antibody binding. Our findings suggest that NA antigenic drift impacts protection against influenza virus infection, thus highlighting the importance of including NA antigenicity for consideration in the optimization of influenza vaccines.


Subject(s)
Influenza A Virus, H3N2 Subtype/enzymology , Influenza A Virus, H3N2 Subtype/immunology , Influenza Vaccines/immunology , Neuraminidase/chemistry , Neuraminidase/immunology , Animals , Antibodies, Monoclonal , Antigens, Viral/genetics , Antigens, Viral/immunology , Catalytic Domain , Crystallography, X-Ray , Disease Models, Animal , Genes, Viral/genetics , Glycosylation , Hong Kong , Humans , Immunogenicity, Vaccine , Influenza A Virus, H3N2 Subtype/genetics , Influenza, Human/prevention & control , Mice , Models, Molecular , Mutation , Neuraminidase/genetics , Orthomyxoviridae Infections/immunology , Protein Conformation , Sequence Analysis, Protein , Viral Proteins/chemistry , Viral Proteins/genetics , Viral Proteins/immunology
13.
J Mol Neurosci ; 69(4): 505-515, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31352588

ABSTRACT

Our study aimed to explore the molecular mechanisms and novel target genes of neuropathic pain via bioinformatics analysis. Gene expression profiling of GSE30691 which was consisted of sciatic nerve lesion and sham control samples at 3 days, 7 days, 21 days, and 40 days (D3, D7, D21, and D40) after injury were downloaded from Gene Expression Omnibus. Differentially expressed genes (DEGs) were identified for all the four time points. Overlapped DEGs for all the four time points were used for functional and weighted co-expression modular analysis. Afterwards, protein-protein interaction (PPI) network was analyzed by MCODE (Molecular Complex Detection) and BiNGO. Pathway network was constructed according to the enriched pathways of PPI network and relevant pathways selected from the Comparative Toxicogenomics Database. There were 355 overlapped DEGs for all the four time points. Two co-expression modules had significant positive correlations with disease. The top ten hub DEGs in the PPI network were Fos, Tp53, Csk, Map2k2, Stat3, Ccl2, Pxn, Tgfb1, Notch1, and Prkacb. Fos, Dusp1, Tp53, Tgfb1, and Map2k2 participated in MAPK signaling pathway, while Csk participated in chemokine signaling pathway. The expressions of Fos, Tp53, Csk, and Map2k2 were significantly increased at D3. Tp53, Csk, and Map2k2 continued overexpressing until at D7, and an elevated tendency in Csk expression could be observed until at D21. The expression of Fos reached up to the highest at D40. Fos, Tp53, Csk, and Map2k2 might be the potential biomarkers related to neuropathic pain.


Subject(s)
Neuralgia/genetics , Peripheral Nerve Injuries/genetics , Protein Interaction Maps , Animals , Biomarkers/metabolism , Gene Regulatory Networks , Neuralgia/etiology , Neuralgia/metabolism , Peripheral Nerve Injuries/complications , Peripheral Nerve Injuries/metabolism , Rats , Sciatic Nerve/injuries
14.
mBio ; 10(2)2019 04 09.
Article in English | MEDLINE | ID: mdl-30967460

ABSTRACT

The effectiveness of influenza vaccines against circulating A(H1N1)pdm09 viruses was modest for several seasons despite the absence of antigenic drift of hemagglutinin (HA), the primary vaccine component. Since antibodies against HA and neuraminidase (NA) contribute independently to protection against disease, antigenic changes in NA may allow A(H1N1)pdm09 viruses to escape from vaccine-induced immunity. In this study, analysis of the specificities of human NA-specific monoclonal antibodies identified antigenic sites that have changed over time. The impact of these differences on in vitro inhibition of enzyme activity was not evident for polyclonal antisera until viruses emerged in 2013 without a predicted glycosylation site at amino acid 386 in NA. Phylogenetic and antigenic cartography demonstrated significant antigenic changes that in most cases aligned with genetic differences. Typical of NA drift, the antigenic difference is observed in one direction, with antibodies against conserved antigenic domains in A/California/7/2009 (CA/09) continuing to inhibit NA of recent A(H1N1)pdm09 viruses reasonably well. However, ferret CA/09-specific antiserum that inhibited the NA of A/Michigan/45/2015 (MI/15) very well in vitro, protected mice against lethal MI/15 infection poorly. These data show that antiserum against the homologous antigen is most effective and suggest the antigenic properties of NA should not be overlooked when selecting viruses for vaccine production.IMPORTANCE The effectiveness of seasonal influenza vaccines against circulating A(H1N1)pdm09 viruses has been modest in recent years, despite the absence of antigenic drift of HA, the primary vaccine component. Human monoclonal antibodies identified antigenic sites in NA that changed early after the new pandemic virus emerged. The reactivity of ferret antisera demonstrated antigenic drift of A(H1N1)pdm09 NA from 2013 onward. Passive transfer of serum raised against A/California/7/2009 was less effective than ferret serum against the homologous virus in protecting mice against a virus with the NA of more recent virus, A/Michigan/45/2015. Given the long-standing observation that NA-inhibiting antibodies are associated with resistance against disease in humans, these data demonstrate the importance of evaluating NA drift and suggest that vaccine effectiveness might be improved by selecting viruses for vaccine production that have NAs antigenically similar to those of circulating influenza viruses.


Subject(s)
Antibodies, Viral/immunology , Antigens, Viral/immunology , Genetic Drift , Influenza A Virus, H1N1 Subtype/immunology , Neuraminidase/immunology , Viral Proteins/immunology , Animals , Antibodies, Monoclonal/immunology , Disease Models, Animal , Ferrets , Immune Evasion , Immunization, Passive , Influenza A Virus, H1N1 Subtype/genetics , Mice , Neuraminidase/genetics , Orthomyxoviridae Infections/prevention & control , Survival Analysis , Treatment Outcome , Viral Proteins/genetics
15.
mBio ; 9(2)2018 04 03.
Article in English | MEDLINE | ID: mdl-29615508

ABSTRACT

Neuraminidase is one of the two surface glycoproteins of influenza A and B viruses. It has enzymatic activity that cleaves terminal sialic acid from glycans, and that activity is essential at several points in the virus life cycle. While neuraminidase is a major target for influenza antivirals, it is largely ignored in vaccine development. Current inactivated influenza virus vaccines might contain neuraminidase, but the antigen quantity and quality are varied and not standardized. While there are data that show a protective role of anti-neuraminidase immunity, many questions remain unanswered. These questions, among others, concern the targeted epitopes or antigenic sites, the potential for antigenic drift, and, connected to that, the breadth of protection, differences in induction of immune responses by vaccination versus infection, mechanisms of protection, the role of mucosal antineuraminidase antibodies, stability, and the immunogenicity of neuraminidase in vaccine formulations. Reagents for analysis of neuraminidase-based immunity are scarce, and assays are not widely used for clinical studies evaluating vaccines. However, efforts to better understand neuraminidase-based immunity have been made recently. A neuraminidase focus group, NAction!, was formed at a Centers of Excellence for Influenza Research and Surveillance meeting at the National Institutes of Health in Bethesda, MD, to promote research that helps to understand neuraminidase-based immunity and how it can contribute to the design of better and broadly protective influenza virus vaccines. Here, we review open questions and knowledge gaps that have been identified by this group and discuss how the gaps can be addressed, with the ultimate goal of designing better influenza virus vaccines.


Subject(s)
Influenza Vaccines/immunology , Neuraminidase/immunology , Orthomyxoviridae/immunology , Drug Discovery/trends , National Institutes of Health (U.S.) , United States
16.
Cell ; 173(2): 417-429.e10, 2018 04 05.
Article in English | MEDLINE | ID: mdl-29625056

ABSTRACT

Antibodies to the hemagglutinin (HA) and neuraminidase (NA) glycoproteins are the major mediators of protection against influenza virus infection. Here, we report that current influenza vaccines poorly display key NA epitopes and rarely induce NA-reactive B cells. Conversely, influenza virus infection induces NA-reactive B cells at a frequency that approaches (H1N1) or exceeds (H3N2) that of HA-reactive B cells. NA-reactive antibodies display broad binding activity spanning the entire history of influenza A virus circulation in humans, including the original pandemic strains of both H1N1 and H3N2 subtypes. The antibodies robustly inhibit the enzymatic activity of NA, including oseltamivir-resistant variants, and provide robust prophylactic protection, including against avian H5N1 viruses, in vivo. When used therapeutically, NA-reactive antibodies protected mice from lethal influenza virus challenge even 48 hr post infection. These findings strongly suggest that influenza vaccines should be optimized to improve targeting of NA for durable and broad protection against divergent influenza strains.


Subject(s)
Antibodies, Monoclonal/immunology , Influenza, Human/pathology , Neuraminidase/immunology , Viral Proteins/immunology , Animals , Birds , Cross Reactions , Epitopes/immunology , Female , HEK293 Cells , Humans , Immunoglobulin G/blood , Immunoglobulin G/immunology , Influenza A Virus, H1N1 Subtype/enzymology , Influenza A Virus, H3N2 Subtype/enzymology , Influenza A Virus, H5N1 Subtype/immunology , Influenza A Virus, H5N1 Subtype/pathogenicity , Influenza, Human/immunology , Mice , Mice, Inbred BALB C , Orthomyxoviridae Infections/pathology , Orthomyxoviridae Infections/prevention & control
17.
Medicine (Baltimore) ; 97(2): e9438, 2018 Jan.
Article in English | MEDLINE | ID: mdl-29480832

ABSTRACT

Studies on the association of maternal diabetes with autism spectrum disorders (ASDs) in offspring provide inconsistent findings; therefore an updated and comprehensive literature review and meta-analysis is necessary to perform in order to evaluate the available evidences.After searching databases systematically, we established the inclusion criteria and selected the eligible studies. In both overall and stratified analyses, the estimated effects were synthesized dependent on the presence or absence of heterogeneity.Twelve articles involving 16 studies were included and synthesized, demonstrating a significant association of maternal diabetes with ASDs among children (relative risk [RR] = 1.48). However, high heterogeneity was observed (I = 56.3%) and publication bias was identified. In terms of the analyses on reliable evidences from case-control studies, heterogeneity and publication bias disappeared, and the risk of ASDs was increased by 62% among diabetic mothers compared with non-diabetic mothers.Maternal diabetes, especially gestational diabetes mellitus, is associated with ASDs in offspring based on a limited number of convincing case-control studies. More large-scale population-based prospective studies are still needed to draw firm conclusions.


Subject(s)
Autism Spectrum Disorder/epidemiology , Diabetes Mellitus/epidemiology , Diabetes Mellitus/etiology , Humans , Mothers
18.
Neuropsychiatr Dis Treat ; 14: 467-477, 2018.
Article in English | MEDLINE | ID: mdl-29445284

ABSTRACT

BACKGROUND: Treatment-resistant depression (TRD) is common and potentially life-threatening in adults, and the benefits and risks of adjunctive aripiprazole in these patients remain controversial. Therefore, we conducted a meta-analysis of randomized controlled trials (RCTs) to assess the efficacy, acceptability, safety, and quality of life of adjunctive aripiprazole in patients with TRD. METHODS: RCTs published in PubMed, Web of Science, and Embase were systematically reviewed to evaluate the efficacy and safety profiles of TRD patients who were treated with adjunctive aripiprazole. The main outcome measures included response rate, remission rate, changes from baseline in Montgomery-Asberg Depression Rating Scale (MADRS), Clinical Global Impression-severity (CGI-S), Clinical Global Impression-improvement (CGI-I), 17-Item Hamilton Rating Scale for Depression (HAM-D17), Sheehan Disability scale (SDS), and Inventory of Depressive Symptomatology Self-Report Scale (IDS-SR), discontinuation due to adverse events, and adverse events. Risk ratio (RR) or weight mean difference with 95% confidence intervals (CIs) were pooled using a fixed-effects or random-effects model according to the heterogeneity among studies. RESULTS: A total of 8 RCTs involving 2,260 patients were included in this meta-analysis. Adjunctive aripiprazole was associated with a significantly higher remission rate (RR =1.64, 95% CI: 1.42 to 1.89; P<0.001) and response rate (RR =1.45, 95% CI: 1.13 to 1.87; P=0.004) than other treatments. Moreover, adjunctive aripiprazole had greater changes in MADRS score, CGI-S score, CGI-I score, HAM-D17 score, SDS score, and IDS-SR score. There were more patients treated with adjunctive aripiprazole who discontinued their treatments due to adverse events. The incidence of adverse events was significantly higher in the adjunctive aripiprazole group than in other treatment groups. CONCLUSION: The adjunctive aripiprazole showed benefits in improving the response rate, remission rate, and the quality of life in patients with TRD. However, clinicians should interpret these findings with caution due to the evidence of potential treatment-related side effects.

19.
J Virol ; 92(4)2018 02 15.
Article in English | MEDLINE | ID: mdl-29167344

ABSTRACT

The fifth wave of A(H7N9) virus infection in China from 2016 to 2017 caused great concern due to the large number of individuals infected, the isolation of drug-resistant viruses, and the emergence of highly pathogenic strains. Antibodies against neuraminidase (NA) provide added benefit to hemagglutinin-specific immunity and may be important contributors to the effectiveness of A(H7N9) vaccines. We generated a panel of mouse monoclonal antibodies (MAbs) to identify antigenic domains on NA of the novel A(H7N9) virus and compared their functional properties. The loop formed in the region of residue 250 (250 loop) and the domain formed by the loops containing residues 370, 400, and 430 were identified as major antigenic regions. MAbs 1E8, 2F6, 10F4, and 11B2, which recognize these two antigenic domains, were characterized in depth. These four MAbs differ in their abilities to inhibit cleavage of small and large substrates (methyl-umbelliferyl-acetyl neuraminic acid [MU-NANA] and fetuin, respectively) in NA inhibition assays. 1E8 and 11B2 did not inhibit NA cleavage of either MU-NANA or fetuin, and 2F6 inhibited cleavage of fetuin alone, whereas 10F4 inhibited cleavage of both substrates. All four MAbs reduced the in vitro spread of viruses carrying either the wild-type N9 or N9 with antiviral-resistant mutations but to different degrees. These MAbs have different in vivo levels of effectiveness: 10F4 was the most effective in protecting mice against challenge with A(H7N9) virus, 2F6 was less effective, and 11B2 failed to protect BALB/c mice at the doses tested. Our study confirms that NA-specific antibodies can protect against A(H7N9) infection and suggests that in vitro properties can be used to rank antibodies with therapeutic potential.IMPORTANCE The novel A(H7N9) viruses that emerged in China in 2013 continue to infect humans, with a high fatality rate. The most recent outbreak resulted in a larger number of human cases than previous epidemic waves. Due to the absence of a licensed vaccine and the emergence of drug-resistant viruses, there is a need to develop alternative approaches to prevent or treat A(H7N9) infection. We have made a panel of mouse monoclonal antibodies (MAbs) specific for neuraminidase (NA) of A(H7N9) viruses; some of these MAbs are effective in inhibiting viruses that are resistant to antivirals used to treat A(H7N9) patients. Binding avidity, inhibition of NA activity, and plaque formation correlated with the effectiveness of these MAbs to protect mice against lethal A(H7N9) virus challenge. This study identifies in vitro measures that can be used to predict the in vivo efficacy of NA-specific antibodies, providing a way to select MAbs for further therapeutic development.


Subject(s)
Antibodies, Monoclonal/therapeutic use , Antibodies, Viral/therapeutic use , Neuraminidase/immunology , Orthomyxoviridae Infections/prevention & control , Viral Proteins/immunology , Animals , Antibodies, Monoclonal/immunology , Antibodies, Viral/immunology , China , Disease Models, Animal , Dogs , Female , HEK293 Cells , Humans , Influenza A Virus, H7N9 Subtype , Lung/pathology , Madin Darby Canine Kidney Cells , Mice , Mice, Inbred BALB C , Orthomyxoviridae Infections/immunology , Reassortant Viruses
20.
J Virol Methods ; 244: 23-28, 2017 06.
Article in English | MEDLINE | ID: mdl-28257802

ABSTRACT

Antibodies that inhibit neuraminidase (NA) activity of influenza virus provide resistance against disease and have been associated with milder epidemics. Although studies have demonstrated a correlation between NA inhibition antibody titers and vaccine efficacy, neither the quantity nor form of NA is measured in seasonal and pandemic influenza vaccines. In this report, we describe development of enzyme-linked immunosorbent assays (ELISAs) that are suitable for quantitation of the native form of NA of subtype N1. The assays use mouse monoclonal antibodies (mAbs) 1H5 and CD6 to capture NAs of viruses, and a different mAb 4E9 to detect bound antigen. The 1H5-capture ELISA detects NAs of seasonal and pandemic H1N1 viruses as well as H5N1 viruses and has a limit of quantitation (LOQ) of 5.5ng/mL for seasonal H1N1A/Brisbane/59/2007 NA. The CD6-capture ELISA is specific for NA of the 2009 pandemic viruses with a LOQ of 67ng/mL for A/California/07/2009 NA. The ELISA signals in both assays are proportional to NA enzymatic activity and correlate with NA immunogenicity. The ELISAs we describe may expedite the development of NA-based influenza vaccines by providing a practical assay to measure NA potency.


Subject(s)
Enzyme-Linked Immunosorbent Assay/methods , Influenza A virus/enzymology , Neuraminidase/analysis , Viral Proteins/analysis , Animals , Antibodies, Monoclonal/immunology , Antibodies, Viral/immunology , Influenza A virus/immunology , Mice , Neuraminidase/immunology , Viral Proteins/immunology
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