RESUMO
Monoclonal antibodies (mAbs) are an attractive therapeutic platform for the prevention and treatment of influenza virus infection. There are two major glycoproteins on the influenza virion surface: hemagglutinin (HA), which is responsible for viral attachment and entry, and neuraminidase (NA), which mediates viral egress by enzymatically cleaving sialic acid to release budding particles from the host cell surface. Broadly neutralizing antibodies (bNAbs) that target the conserved HA central stalk region, such as CR9114, can inhibit both viral entry and egress. More recently, broadly binding mAbs that engage and inhibit the NA active site, such as 1G01, have been described to prevent viral egress. Here, we engineered bispecific antibodies (bsAbs) that combine the variable domains of CR9114 and 1G01 into a single molecule and evaluated if simultaneous targeting of two different glycoproteins improved antiviral properties in vitro and in vivo. Several CR9114/1G01 bsAbs were generated with various configurations of the two sets of the variable domains ("bsAb formats"). We found that combinations employing the addition of a single-chain variable fragment in the hinge region of an IgG scaffold had the best properties in terms of expression, stability, and binding. Further characterization of selected bsAbs showed potent neutralizing and egress-inhibiting activity. One such bsAb ("hSC_CR9114_1G01") provided higher levels of prophylactic protection from mortality and morbidity upon challenge with H1N1 than either of the parental mAbs at low dosing (1 mg/kg). These results highlight the potential use of bsAbs that simultaneously target HA and NA as new influenza immunotherapeutics. IMPORTANCE: Infection by the influenza virus remains a global health burden. The approaches utilized here to augment the activity of broadly protective influenza virus antibodies may lead to a new class of immunotherapies with enhanced activity.
Assuntos
Anticorpos Biespecíficos , Anticorpos Antivirais , Glicoproteínas de Hemaglutininação de Vírus da Influenza , Neuraminidase , Neuraminidase/imunologia , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Anticorpos Biespecíficos/imunologia , Anticorpos Biespecíficos/farmacologia , Anticorpos Antivirais/imunologia , Animais , Humanos , Camundongos , Infecções por Orthomyxoviridae/prevenção & controle , Infecções por Orthomyxoviridae/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Monoclonais/imunologia , Influenza Humana/imunologia , Influenza Humana/prevenção & controle , Influenza Humana/virologia , Camundongos Endogâmicos BALB C , Vírus da Influenza A Subtipo H1N1/imunologia , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacosRESUMO
Germinal centers (GC) are microanatomical lymphoid structures where affinity-matured memory B cells and long-lived bone marrow plasma cells are primarily generated. It is unclear how the maturation of B cells within the GC impacts the breadth and durability of B cell responses to influenza vaccination in humans. We used fine needle aspiration of draining lymph nodes to longitudinally track antigen-specific GC B cell responses to seasonal influenza vaccination. Antigen-specific GC B cells persisted for at least 13 wk after vaccination in two out of seven individuals. Monoclonal antibodies (mAbs) derived from persisting GC B cell clones exhibit enhanced binding affinity and breadth to influenza hemagglutinin (HA) antigens compared with related GC clonotypes isolated earlier in the response. Structural studies of early and late GC-derived mAbs from one clonal lineage in complex with H1 and H5 HAs revealed an altered binding footprint. Our study shows that inducing sustained GC reactions after influenza vaccination in humans supports the maturation of responding B cells.
Assuntos
Linfócitos B , Centro Germinativo , Vacinas contra Influenza , Vacinação , Centro Germinativo/imunologia , Humanos , Vacinas contra Influenza/imunologia , Linfócitos B/imunologia , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Influenza Humana/imunologia , Influenza Humana/prevenção & controle , Anticorpos Antivirais/imunologia , Anticorpos Monoclonais/imunologia , Adulto , Feminino , Masculino , Pessoa de Meia-IdadeRESUMO
IMPORTANCE: Currently, many groups are focusing on isolating both neutralizing and non-neutralizing antibodies to the mutation-prone hemagglutinin as a tool to treat or prevent influenza virus infection. Less is known about the level of protection induced by non-neutralizing antibodies that target conserved internal influenza virus proteins. Such non-neutralizing antibodies could provide an alternative pathway to induce broad cross-reactive protection against multiple influenza virus serotypes and subtypes by partially overcoming influenza virus escape mediated by antigenic drift and shift. Accordingly, more information about the level of protection and potential mechanism(s) of action of non-neutralizing antibodies targeting internal influenza virus proteins could be useful for the design of broadly protective and universal influenza virus vaccines.
Assuntos
Anticorpos Monoclonais , Vírus da Influenza A , Proteínas do Nucleocapsídeo , Proteínas da Matriz Viral , Humanos , Anticorpos Monoclonais/imunologia , Anticorpos Antivirais , Glicoproteínas de Hemaglutininação de Vírus da Influenza , Influenza Humana , Proteínas da Matriz Viral/imunologia , Proteínas do Nucleocapsídeo/imunologiaRESUMO
IMPORTANCE: Vaccines that can slow respiratory virus transmission in the population are urgently needed for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and influenza virus. Here, we describe how a recombinant neuraminidase-based influenza virus vaccine reduces transmission in vaccinated guinea pigs in an exposure intensity-based manner.
Assuntos
Vacinas contra Influenza , Neuraminidase , Infecções por Orthomyxoviridae , Animais , Cobaias , Anticorpos Antivirais , Vírus da Influenza B , Vacinas contra Influenza/imunologia , Neuraminidase/imunologia , Infecções por Orthomyxoviridae/prevenção & controle , Proteínas Recombinantes , VacinaçãoRESUMO
Neuraminidase (NA) is one of the two influenza virus surface glycoproteins, and antibodies that target it are an independent correlate of protection. However, our current understanding of NA antigenicity is incomplete. Here, we describe human monoclonal antibodies (mAbs) from a patient with a pandemic H1N1 virus infection in 2009. Two mAbs exhibited broad reactivity and inhibited NA enzyme activity of seasonal H1N1 viruses circulating before and after 2009, as well as viruses with avian or swine N1s. The mAbs provided robust protection from lethal challenge with human H1N1 and avian H5N1 viruses in mice, and both target an epitope on the lateral face of NA. In summary, we identified two broadly protective NA antibodies that share a novel epitope, inhibited NA activity, and provide protection against virus challenge in mice. Our work reaffirms that NA should be included as a target in future broadly protective or universal influenza virus vaccines.
Assuntos
Anticorpos Monoclonais , Anticorpos Antivirais , Vírus da Influenza A Subtipo H1N1 , Influenza Humana , Neuraminidase , Anticorpos Monoclonais/isolamento & purificação , Anticorpos Monoclonais/metabolismo , Anticorpos Antivirais/isolamento & purificação , Anticorpos Antivirais/metabolismo , Neuraminidase/química , Neuraminidase/metabolismo , Humanos , Fragmentos Fab das Imunoglobulinas/química , Microscopia Crioeletrônica , Epitopos , Camundongos Endogâmicos BALB C , Animais , Camundongos , Influenza Humana/tratamento farmacológico , Modelos Animais de DoençasRESUMO
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.
Assuntos
Anticorpos Monoclonais , Vírus da Influenza A Subtipo H3N2 , Neuraminidase , Humanos , Anticorpos Monoclonais/química , Anticorpos Monoclonais/imunologia , Anticorpos Antivirais/química , Anticorpos Antivirais/metabolismo , Domínio Catalítico/imunologia , Domínio Catalítico/fisiologia , Glicosilação , Glicoproteínas de Hemaglutininação de Vírus da Influenza , Vírus da Influenza A , Vírus da Influenza A Subtipo H3N2/imunologia , Vírus da Influenza A Subtipo H3N2/metabolismo , Influenza Humana/imunologia , Influenza Humana/metabolismo , Neuraminidase/química , Neuraminidase/imunologiaRESUMO
Combined vaccine formulations targeting not only hemagglutinin but also other influenza virus antigens could form the basis for a universal influenza virus vaccine that has the potential to elicit long-lasting, broadly cross-reactive immune responses. Lipid nanoparticle (LNP)-encapsulated messenger RNA (mRNA) vaccines can be utilized to efficiently target multiple antigens with a single vaccine. Here, we assessed the immunogenicity and protective efficacy of nucleoside-modified mRNA-LNP vaccines that contain four influenza A group 2 virus antigens (hemagglutinin stalk, neuraminidase, matrix protein 2, and nucleoprotein) in mice. We found that all vaccine components induced antigen-specific cellular and humoral immune responses after administration of a single dose. While the monovalent formulations were not exclusively protective, the combined quadrivalent formulation protected mice from all challenge viruses, including a relevant H1N1 influenza virus group 1 strain, with minimal weight loss. Importantly, the combined vaccine protected from morbidity at a dose of 125 ng per antigen after a single vaccination in mice. With these findings, we confidently conclude that the nucleoside-modified mRNA-LNP platform can be used to elicit protection against a large panel of influenza viruses.
Assuntos
Vírus da Influenza A Subtipo H1N1 , Vacinas contra Influenza , Influenza Humana , Infecções por Orthomyxoviridae , Camundongos , Animais , Humanos , Vírus da Influenza A Subtipo H1N1/genética , Nucleosídeos , Hemaglutininas , Vacinas Combinadas , RNA Mensageiro/genética , Anticorpos Antivirais , Vacinação , Glicoproteínas de Hemaglutininação de Vírus da Influenza , Vacinas de mRNARESUMO
Mucosal vaccines and vaccines that block pathogen transmission are under-appreciated in vaccine development. However, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has shown that blocking viral transmission is an important attribute of efficient vaccines. Here, we investigated if recombinant influenza virus neuraminidase (NA) vaccines delivered at a mucosal site could protect from onward transmission of influenza B viruses in the guinea pig model. We tested four different scenarios in which sequential transmission was investigated in chains of four guinea pigs. The variables tested included a low and a high viral inoculum (104 vs 105 plaque forming units) in the initial donor guinea pig and variation of exposure/cohousing time (1 day vs 6 days). In three out of four scenarios - low inoculum-long exposure, low inoculum-short exposure and high inoculum-short exposure - transmission chains were efficiently blocked. Based on this data we believe an intranasal recombinant NA vaccine could be used to efficiently curtail influenza virus spread in the human population during influenza epidemics.
RESUMO
Current influenza virus vaccines and antivirals have limitations, some of which disproportionately affect their utilization against influenza B viruses. To inform ongoing efforts to address the considerable global burden of influenza B viruses, we previously described five murine monoclonal antibodies that broadly bind conserved epitopes on the neuraminidase of influenza B viruses and protect against lethal challenge in a mouse model when delivered via intraperitoneal injection. Here, we validate the continued relevance of these antibodies by demonstrating that their protective effects extend to lethal challenge with mouse-adapted influenza B viruses recently isolated from humans. We also found that humanization of murine antibodies 1F2 and 4F11 resulted in molecules that retain the ability to protect mice from lethal challenge when administered prophylactically. Intranasal administration as an alternative route of 1F2 delivery revealed no differences in the mouse challenge model compared to intraperitoneal injection, supporting further assessment of this more targeted and convenient administration method. Lastly, we evaluated the potential for intranasal 1F2 administration initiated 1 day after infection to prevent transmission of an influenza B virus between cocaged guinea pigs. Here, we observed a 40% rate of transmission with the 1F2 antibody administered to the infected donor compared to 100% transmission with administration of an irrelevant control antibody. These data suggest that intranasal administration could be a viable route of administration for antibody therapeutics. Collectively, these findings demonstrate the potential of broad antineuraminidase antibodies as therapeutics to prevent and treat infections caused by influenza B viruses. IMPORTANCE The global health burden of influenza B viruses, especially in children, has long been underappreciated. Although two antigenically distinct influenza B virus lineages cocirculated before the coronavirus disease 2019 (COVID-19) pandemic, the commonly used trivalent seasonal vaccines contain antigens from only one influenza B virus, providing limited cross-protection against viruses of the other lineage. Additionally, studies have called into question the clinical effectiveness of the neuraminidase inhibitors that comprise the majority of available antivirals in treating influenza B virus infections. We previously described antibodies that bind broadly to neuraminidases of influenza B viruses across decades of antigenic evolution and potently protect mice against lethal challenge. Here we appraise additional factors to develop these antineuraminidase antibodies as antivirals to prevent and treat infections caused by an extensive range of influenza B viruses. In addition this work assesses recent clinical isolates belonging to the two influenza B virus lineages, finding evidence supporting the development of these antibodies for prophylactic and therapeutic use.
Assuntos
Vacinas contra Influenza , Infecções por Orthomyxoviridae , Animais , Cobaias , Humanos , Camundongos , Anticorpos Monoclonais/uso terapêutico , Anticorpos Antivirais , Antivirais , Modelos Animais de Doenças , Epitopos , Vírus da Influenza B , NeuraminidaseRESUMO
Messenger RNA (mRNA) vaccines represent a new, effective vaccine platform with high capacity for rapid development. Generation of a universal influenza virus vaccine with the potential to elicit long-lasting, broadly cross-reactive immune responses is a necessity for reducing influenza-associated morbidity and mortality. Here we focus on the development of a universal influenza B virus vaccine based on the lipid nanoparticle-encapsulated nucleoside-modified mRNA (mRNA-LNP) platform. We evaluate vaccine candidates based on different target antigens that afford protection against challenge with ancestral and recent influenza B viruses from both antigenic lineages. A pentavalent vaccine combining all tested antigens protects mice from morbidity at a very low dose of 50 ng per antigen after a single vaccination. These findings support the further advancement of nucleoside-modified mRNA-LNPs expressing multiple conserved antigens as universal influenza virus vaccine candidates.
Assuntos
Vacinas contra Influenza , Infecções por Orthomyxoviridae , Animais , Anticorpos Antivirais , Glicoproteínas de Hemaglutininação de Vírus da Influenza , Vírus da Influenza B/genética , Lipossomos , Camundongos , Nanopartículas , Nucleosídeos , RNA Mensageiro/genética , Vacinas Combinadas , Vacinas Sintéticas , Vacinas de mRNARESUMO
Influenza virus neuraminidase (NA)-targeting antibodies are an independent correlate of protection against influenza. Antibodies against the NA act by blocking enzymatic activity, preventing virus release and transmission. As we advance the development of improved influenza virus vaccines that incorporate standard amounts of NA antigen, it is important to identify the antigenic targets of human monoclonal antibodies (mAbs). Here, we describe escape mutants generated by serial passage of A/Netherlands/602/2009 (H1N1)pdm09 in the presence of human anti-N1 mAbs. We observed escape mutations on the head domain of the N1 protein around the enzymatic site (S364N, N369T, and R430Q) and also detected escape mutations located on the sides and bottom of the NA (N88D, N270D, and Q313K/R). This work increases our understanding of how human antibody responses target the N1 protein. IMPORTANCE As improved influenza virus vaccines are being developed, the influenza virus neuraminidase (NA) is becoming an important new target for immune responses. By identifying novel epitopes of anti-NA antibodies, we can improve vaccine design. Additionally, characterizing escape mutations in these epitopes aids in identifying NA antigenic drift in circulating viruses.
Assuntos
Vírus da Influenza A Subtipo H1N1 , Vacinas contra Influenza , Influenza Humana , Anticorpos Monoclonais , Anticorpos Antivirais/metabolismo , Epitopos/imunologia , Humanos , Vírus da Influenza A Subtipo H1N1/enzimologia , Vírus da Influenza A Subtipo H1N1/genética , Vacinas contra Influenza/genética , Vacinas contra Influenza/imunologia , Influenza Humana/virologia , Mutação , Neuraminidase/química , Neuraminidase/genética , Neuraminidase/imunologiaRESUMO
Coronavirus disease 2019 (COVID-19) in humans has a wide range of presentations, ranging from asymptomatic or mild symptoms to severe illness. Suitable animal models mimicking varying degrees of clinical disease manifestations could expedite development of therapeutics and vaccines for COVID-19. Here we demonstrate that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection resulted in subclinical disease in rhesus macaques with mild pneumonia and clinical disease in Syrian hamsters with severe pneumonia. SARS-CoV-2 infection was confirmed by formalin-fixed, paraffin-embedded (FFPE) polymerase chain reaction (PCR), immunohistochemistry, or in situ hybridization. Replicating virus in the lungs was identified using in situ hybridization or virus plaque forming assays. Viral encephalitis, reported in some COVID-19 patients, was identified in one macaque and was confirmed with immunohistochemistry. There was no evidence of encephalitis in hamsters. Severity and distribution of lung inflammation were substantially more in hamsters compared with macaques and exhibited vascular changes and virus-induced cytopathic changes as seen in COVID-19 patients. Neither the hamster nor macaque models demonstrated evidence for multisystemic inflammatory syndrome (MIS). Data presented here demonstrate that macaques may be appropriate for mechanistic studies of mild asymptomatic COVID-19 pneumonia and COVID-19-associated encephalitis, whereas Syrian hamsters may be more suited to study severe COVID-19 pneumonia.
Assuntos
COVID-19 , Encefalite , Animais , Vacinas contra COVID-19 , Cricetinae , Modelos Animais de Doenças , Encefalite/patologia , Humanos , Pulmão/patologia , Macaca mulatta , Mesocricetus , SARS-CoV-2RESUMO
Conventional influenza vaccines fail to confer broad protection against diverse influenza A viruses with pandemic potential. Efforts to develop a universal influenza virus vaccine include refocusing immunity towards the highly conserved stalk domain of the influenza virus surface glycoprotein, hemagglutinin (HA). We constructed a non-replicating adenoviral (Ad) vector, encoding a secreted form of H1 HA, to evaluate HA stalk-focused immunity. The Ad5_H1 vaccine was tested in mice for its ability to elicit broad, cross-reactive protection against homologous, heterologous, and heterosubtypic lethal challenge in a single-shot immunization regimen. Ad5_H1 elicited hemagglutination inhibition (HI+) active antibodies (Abs), which conferred 100% sterilizing protection from homologous H1N1 challenge. Furthermore, Ad5_H1 rapidly induced H1-stalk-specific Abs with Fc-mediated effector function activity, in addition to stimulating both CD4+ and CD8+ stalk-specific T cell responses. This phenotype of immunity provided 100% protection from lethal challenge with a head-mismatched, reassortant influenza virus bearing a chimeric HA, cH6/1, in a stalk-mediated manner. Most importantly, 100% protection from mortality following lethal challenge with a heterosubtypic avian influenza virus, H5N1, was observed following a single immunization with Ad5_H1. In conclusion, Ad-based influenza vaccines can elicit significant breadth of protection in naive animals and could be considered for pandemic preparedness and stockpiling.
Assuntos
Vírus da Influenza A Subtipo H1N1 , Virus da Influenza A Subtipo H5N1 , Vírus da Influenza A , Vacinas contra Influenza , Influenza Humana , Infecções por Orthomyxoviridae , Adenoviridae/genética , Animais , Anticorpos Antivirais , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Hemaglutininas , Humanos , Virus da Influenza A Subtipo H5N1/genética , Influenza Humana/prevenção & controle , Camundongos , Camundongos Endogâmicos BALB CRESUMO
Broadly neutralizing antibodies that target epitopes of haemagglutinin on the influenza virus have the potential to provide near universal protection against influenza virus infection1. However, viral mutants that escape broadly neutralizing antibodies have been reported2,3. The identification of broadly neutralizing antibody classes that can neutralize viral escape mutants is critical for universal influenza virus vaccine design. Here we report a distinct class of broadly neutralizing antibodies that target a discrete membrane-proximal anchor epitope of the haemagglutinin stalk domain. Anchor epitope-targeting antibodies are broadly neutralizing across H1 viruses and can cross-react with H2 and H5 viruses that are a pandemic threat. Antibodies that target this anchor epitope utilize a highly restricted repertoire, which encodes two public binding motifs that make extensive contacts with conserved residues in the fusion peptide. Moreover, anchor epitope-targeting B cells are common in the human memory B cell repertoire and were recalled in humans by an oil-in-water adjuvanted chimeric haemagglutinin vaccine4,5, which is a potential universal influenza virus vaccine. To maximize protection against seasonal and pandemic influenza viruses, vaccines should aim to boost this previously untapped source of broadly neutralizing antibodies that are widespread in the human memory B cell pool.
Assuntos
Anticorpos Neutralizantes , Anticorpos Antivirais , Anticorpos Amplamente Neutralizantes , Epitopos , Glicoproteínas de Hemaglutininação de Vírus da Influenza , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Anticorpos Amplamente Neutralizantes/imunologia , Epitopos/química , Epitopos/imunologia , Glicoproteínas de Hemaglutininação de Vírus da Influenza/química , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Humanos , Vacinas contra Influenza/imunologia , Influenza Humana/imunologia , Influenza Humana/prevenção & controle , Influenza Humana/virologia , Células B de Memória/imunologiaRESUMO
To determine if biological sex and age intersect to affect universal influenza vaccine-induced immunity, adult and aged male and female C57BL/6 mice were sequentially immunized with a chimeric-hemagglutinin (cHA) stalk-based H1 vaccine. Adult mice developed greater quantity and quality of H1-stalk antibodies, that were more cross-reactive with other group 1, but not group 2, influenza viruses, than aged mice. The vaccine did not induce neutralizing or hemagglutination inhibition antibodies, but rather antibody-dependent cellular cytotoxicity, which was greater in adult than aged mice. Vaccinated adult mice were better protected than aged mice after challenge with 2009 H1N1 virus, experiencing less morbidity and having lower pulmonary virus titers. The age-associated decline in immunity and protection was consistently greater among females than males, with the reduction in immunity and protection for aged as compared with adult females often being the sole comparison driving the overall age-associated significant differences. The age-associated reduction in stalk-based immunity in females was not, however, associated with changes in estradiol. To determine if the better antibodies in adults could be utilized to protect aged mice, serum was passively transferred from vaccinated adult mice into naïve sex-matched aged mice. Even with transferred serum from young adult mice, aged females still suffered greater morbidity than aged males. These data suggest there are sex-dependent effects of aging on cHA-based universal influenza virus vaccine-induced immunity that cannot be reversed through transfer of serum from young animals. The lack of consideration of sex-specific effects of aging on immunity could hinder efforts toward universal vaccines.
Assuntos
Vírus da Influenza A Subtipo H1N1 , Vacinas contra Influenza , Influenza Humana , Infecções por Orthomyxoviridae , Fatores Etários , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Modelos Animais de Doenças , Feminino , Glicoproteínas de Hemaglutininação de Vírus da Influenza , Hemaglutininas , Humanos , Vírus da Influenza A Subtipo H1N1/imunologia , Vacinas contra Influenza/imunologia , Influenza Humana/imunologia , Influenza Humana/prevenção & controle , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/prevenção & controle , Fatores SexuaisRESUMO
The public health burden caused by influenza virus infections is not adequately addressed with existing vaccines and antivirals. Identifying approaches that interfere with human-to-human transmission of influenza viruses remains a pressing need. The importance of neuraminidase (NA) activity for the replication and spread of influenza viruses led us to investigate whether broadly reactive human anti-NA monoclonal antibodies (MAbs) could affect airborne transmission of the virus using the guinea pig model. In that model, infection with recent influenza virus clinical isolates resulted in 100% transmission from inoculated donors to recipients in an airborne transmission setting. Anti-NA MAbs were administered either to the inoculated animals on days 1, 2, and 4 after infection or to the naive contacts on days 2 and 4 after donor infection. Administration of NA-1G01, a broadly cross-reactive anti-NA MAb, to either the donor or recipient reduced transmission of the A/New York City/PV02669/2019 (H1N1) and A/New York City/PV01148/2018 (H3N2) viruses. Administration of 1000-3C05, an anti-N1 MAb, to either the donor or recipient reduced transmission of A/New York City/PV02669/2019 (H1N1) virus but did not reduce transmission of A/New York City/PV01148 (H3N2) virus. Conversely, 229-2C06, an anti-N2 MAb, reduced transmission of A/New York City/PV01148 (H3N2) but did not impact transmission of A/New York City/PV02669/2019 (H1N1) virus. Our work demonstrates that anti-NA MAbs could be further developed into prophylactic or therapeutic agents to prevent influenza virus transmission to control viral spread. IMPORTANCE The burden of influenza remains substantial despite unremitting efforts to reduce the magnitude of seasonal influenza epidemics and prepare for pandemics. Although vaccination remains the mainstay of these efforts, current vaccines are designed to stimulate an immune response against the viral hemagglutinin. Interest in the role immunity against neuraminidase plays in influenza virus infection and transmission has recently surged. Human antibodies that bind broadly to neuraminidases of diverse influenza viruses and protect mice against lethal viral challenge have previously been characterized. Here, we show that three such antibodies inhibit the neuraminidase activity of recent isolates and reduce their airborne transmission in a guinea pig model. In addition to contributing to the accumulating support for incorporating neuraminidase as a vaccine antigen, these findings also demonstrate the potential of direct administration of anti-neuraminidase antibodies to individuals infected with influenza virus and to individuals for postexposure prophylaxis to prevent the spread of influenza virus.
Assuntos
Anticorpos Antivirais/uso terapêutico , Neuraminidase/imunologia , Infecções por Orthomyxoviridae/prevenção & controle , Proteínas Virais/imunologia , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/uso terapêutico , Anticorpos Antivirais/imunologia , Reações Cruzadas , Cobaias , Humanos , Imunização Passiva , Vírus da Influenza A Subtipo H1N1/imunologia , Vírus da Influenza A Subtipo H3N2/imunologia , Influenza Humana/imunologia , Infecções por Orthomyxoviridae/transmissãoRESUMO
Current seasonal influenza virus vaccines do not induce robust immune responses to neuraminidase. Several factors, including immunodominance of hemagglutinin over neuraminidase, instability of neuraminidase in vaccine formulations, and variable, nonstandardized amounts of neuraminidase in the vaccines, may contribute to this effect. However, vaccines that induce strong antineuraminidase immune responses would be beneficial, as they are highly protective. Furthermore, antigenic drift is slower for neuraminidase than for hemagglutinin, potentially providing broader coverage. Here, we designed stabilized recombinant versions of neuraminidase by replacing the N-terminal cytoplasmic domain, transmembrane, and extracellular stalk with tetramerization domains from the measles or Sendai virus phosphoprotein or from an Arabidopsis thaliana transcription factor. The measles virus tetramerization domain-based construct, termed N1-MPP, was chosen for further evaluation, as it retained antigenicity, neuraminidase activity, and structural integrity and provided robust protection in vivo against lethal virus challenge in the mouse model. We tested N1-MPP as a standalone vaccine, admixed with seasonal influenza virus vaccines, or given with seasonal influenza virus vaccines but in the other leg of the mouse. Admixture with different formulations of seasonal vaccines led to a weak neuraminidase response, suggesting a dominant effect of hemagglutinin over neuraminidase when administered in the same formulation. However, administration of neuraminidase alone or with seasonal vaccine administered in the alternate leg of the mouse induced robust antibody responses. Thus, this recombinant neuraminidase construct is a promising vaccine antigen that may enhance and broaden protection against seasonal influenza viruses. IMPORTANCE Influenza virus infections remain a high risk to human health, causing up to 650,000 deaths worldwide every year, with an enormous burden on the health care system. Since currently available seasonal vaccines are only partially effective and often mismatched to the circulating strains, a broader protective influenza virus vaccine is needed. Here, we generated a recombinant influenza virus vaccine candidate based on the more conserved neuraminidase surface glycoprotein in order to induce a robust and broader protective immune response against a variety of circulating influenza virus strains.
Assuntos
Vacinas contra Influenza/imunologia , Influenza Humana/prevenção & controle , Vírus do Sarampo/imunologia , Neuraminidase/imunologia , Fosfoproteínas/imunologia , Proteínas Virais/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Antivirais/imunologia , Deriva e Deslocamento Antigênicos , Reações Cruzadas , Humanos , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H1N1/imunologia , Vírus da Influenza A Subtipo H1N1/fisiologia , Vacinas contra Influenza/administração & dosagem , Vacinas contra Influenza/química , Vacinas contra Influenza/genética , Influenza Humana/imunologia , Influenza Humana/virologia , Vírus do Sarampo/química , Vírus do Sarampo/genética , Camundongos , Camundongos Endogâmicos BALB C , Neuraminidase/administração & dosagem , Neuraminidase/química , Neuraminidase/genética , Fosfoproteínas/química , Fosfoproteínas/genética , Domínios Proteicos , Alinhamento de Sequência , Vacinação , Proteínas Virais/administração & dosagem , Proteínas Virais/química , Proteínas Virais/genéticaRESUMO
Nucleoside-modified, lipid nanoparticle-encapsulated mRNAs have recently emerged as suitable vaccines for influenza viruses and other pathogens in part because the platform allows delivery of multiple antigens in a single immunization. mRNA vaccines allow for easy antigen modification, enabling rapid iterative design. We studied protein modifications such as mutating functional sites, changing secretion potential, and altering protein conformation, which could improve the safety and/or potency of mRNA-based influenza virus vaccines. Mice were vaccinated intradermally with wild-type or mutant constructs of influenza virus hemagglutinin (HA), neuraminidase (NA), matrix protein 2 (M2), nucleoprotein (NP), or matrix protein 1 (M1). Membrane-bound HA constructs elicited more potent and protective antibody responses than secreted forms. Altering the catalytic site of NA to reduce enzymatic activity decreased reactogenicity while protective immunity was maintained. Disruption of M2 ion channel activity improved immunogenicity and protective efficacy. A comparison of internal proteins NP and M1 revealed the superiority of NP in conferring protection from influenza virus challenge. These findings support the use of the nucleoside-modified mRNA platform for guided antigen design for influenza virus with extension to other pathogens.
RESUMO
Remodelling of the extracellular matrix (ECM) by ECM metalloproteinases is increasingly being associated with regulation of immune cell function. ECM metalloproteinases, including Matrix Metalloproteinases (MMPs), A Disintegrin and Metalloproteinases (ADAMs) and ADAMs with Thombospondin-1 motifs (ADAMTS) play a vital role in pathogen defence and have been shown to influence migration of immune cells. This review provides a current summary of the role of ECM enzymes in immune cell migration and function and discusses opportunities and limitations for development of diagnostic and therapeutic strategies targeting metalloproteinase expression and activity in the context of infectious disease.
RESUMO
The influenza virus neuraminidase (NA) is primarily involved in the release of progeny viruses from infected cells-a critical role for virus replication. Compared to the immuno-dominant hemagglutinin, there are fewer NA subtypes, and NA experiences a slower rate of antigenic drift and reduced immune selection pressure. Furthermore, NA inhibiting antibodies prevent viral egress, thus preventing viral spread. Anti-NA immunity can lessen disease severity, reduce viral shedding, and decrease viral lung titers in humans and various animal models. As a result, there has been a concerted effort to investigate the possibilities of incorporating immunogenic forms of NA as a vaccine antigen in future vaccine formulations. In this review, we discuss NA-based immunity and describe several human NA-specific monoclonal antibodies (mAbs) that have a broad range of protection. We also review vaccine platforms that are investigating NA antigens in pre-clinical models and their potential use for next-generation influenza virus vaccines. The evidence presented here supports the inclusion of immunogenic NA in future influenza virus vaccines.