RESUMO
Development of improved approaches for HIV-1 prevention will likely be required for a durable end to the global AIDS pandemic. Recent advances in preclinical studies and early phase clinical trials offer renewed promise for immunologic strategies for blocking acquisition of HIV-1 infection. Clinical trials are currently underway to evaluate the efficacy of two vaccine candidates and a broadly neutralizing antibody (bNAb) to prevent HIV-1 infection in humans. However, the vast diversity of HIV-1 is a major challenge for both active and passive immunization. Here we review current immunologic strategies for HIV-1 prevention, with a focus on current and next-generation vaccines and bNAbs.
Assuntos
Vacinas contra a AIDS/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Anti-HIV/imunologia , Infecções por HIV/imunologia , Infecções por HIV/prevenção & controle , HIV-1/imunologia , Interações Hospedeiro-Patógeno/imunologia , Vacinas contra a AIDS/administração & dosagem , Animais , Ensaios Clínicos como Assunto , Gerenciamento Clínico , Variação Genética , Infecções por HIV/virologia , HIV-1/genética , Humanos , Imunização Passiva , RNA Viral , Relação Estrutura-Atividade , Linfócitos T/imunologia , Linfócitos T/metabolismo , Proteínas Virais/química , Proteínas Virais/genéticaRESUMO
The mpox outbreak of 2022-2023 involved rapid global spread in men who have sex with men. We infected 18 rhesus macaques with mpox by the intravenous, intradermal, and intrarectal routes and observed robust antibody and T cell responses following all three routes of infection. Numerous skin lesions and high plasma viral loads were observed following intravenous and intradermal infection. Skin lesions peaked on day 10 and resolved by day 28 following infection. On day 28, we re-challenged all convalescent and 3 naive animals with mpox. All convalescent animals were protected against re-challenge. Transcriptomic studies showed upregulation of innate and inflammatory responses and downregulation of collagen formation and extracellular matrix organization following challenge, as well as rapid activation of T cell and plasma cell responses following re-challenge. These data suggest key mechanistic insights into mpox pathogenesis and immunity. This macaque model should prove useful for evaluating mpox vaccines and therapeutics.
Assuntos
Macaca mulatta , Monkeypox virus , Mpox , Animais , Humanos , Masculino , Homossexualidade Masculina , Mpox/imunologia , Minorias Sexuais e de Gênero , Monkeypox virus/fisiologiaRESUMO
The rapid spread of the SARS-CoV-2 Omicron (B.1.1.529) variant, including in highly vaccinated populations, has raised important questions about the efficacy of current vaccines. In this study, we show that the mRNA-based BNT162b2 vaccine and the adenovirus-vector-based Ad26.COV2.S vaccine provide robust protection against high-dose challenge with the SARS-CoV-2 Omicron variant in cynomolgus macaques. We vaccinated 30 macaques with homologous and heterologous prime-boost regimens with BNT162b2 and Ad26.COV2.S. Following Omicron challenge, vaccinated macaques demonstrated rapid control of virus in bronchoalveolar lavage, and most vaccinated animals also controlled virus in nasal swabs. However, 4 vaccinated animals that had moderate Omicron-neutralizing antibody titers and undetectable Omicron CD8+ T cell responses failed to control virus in the upper respiratory tract. Moreover, virologic control correlated with both antibody and T cell responses. These data suggest that both humoral and cellular immune responses contribute to vaccine protection against a highly mutated SARS-CoV-2 variant.
Assuntos
Ad26COVS1/imunologia , Vacina BNT162/imunologia , COVID-19 , Macaca , SARS-CoV-2 , Ad26COVS1/administração & dosagem , Animais , Anticorpos Neutralizantes , Anticorpos Antivirais , Vacina BNT162/administração & dosagem , COVID-19/imunologia , COVID-19/prevenção & controle , Linfócitos T/imunologiaRESUMO
Vaccines are critical tools for maintaining global health. Traditional vaccine technologies have been used across a wide range of bacterial and viral pathogens, yet there are a number of examples where they have not been successful, such as for persistent infections, rapidly evolving pathogens with high sequence variability, complex viral antigens, and emerging pathogens. Novel technologies such as nucleic acid and viral vector vaccines offer the potential to revolutionize vaccine development as they are well-suited to address existing technology limitations. In this review, we discuss the current state of RNA vaccines, recombinant adenovirus vector-based vaccines, and advances from biomaterials and engineering that address these important public health challenges.
Assuntos
Vacinas contra COVID-19/imunologia , Vacinas contra COVID-19/uso terapêutico , COVID-19/prevenção & controle , SARS-CoV-2/imunologia , Vacinas Sintéticas/imunologia , Vacinas Sintéticas/uso terapêutico , Adenoviridae/genética , Animais , Antígenos Virais/genética , Materiais Biocompatíveis , COVID-19/virologia , Sistemas de Liberação de Medicamentos/métodos , Vetores Genéticos/imunologia , Humanos , Imunogenicidade da Vacina , Lipossomos , Nanopartículas , RNA Mensageiro/síntese química , RNA Mensageiro/imunologia , Vacinas de mRNARESUMO
We previously reported that a single immunization with an adenovirus serotype 26 (Ad26)-vector-based vaccine expressing an optimized SARS-CoV-2 spike (Ad26.COV2.S) protected rhesus macaques against SARS-CoV-2 challenge. To evaluate reduced doses of Ad26.COV2.S, 30 rhesus macaques were immunized once with 1 × 1011, 5 × 1010, 1.125 × 1010, or 2 × 109 viral particles (vp) Ad26.COV2.S or sham and were challenged with SARS-CoV-2. Vaccine doses as low as 2 × 109 vp provided robust protection in bronchoalveolar lavage, whereas doses of 1.125 × 1010 vp were required for protection in nasal swabs. Activated memory B cells and binding or neutralizing antibody titers following vaccination correlated with protective efficacy. At suboptimal vaccine doses, viral breakthrough was observed but did not show enhancement of disease. These data demonstrate that a single immunization with relatively low dose of Ad26.COV2.S effectively protected against SARS-CoV-2 challenge in rhesus macaques, although a higher vaccine dose may be required for protection in the upper respiratory tract.
Assuntos
Adenoviridae/imunologia , Vacinas contra COVID-19/imunologia , COVID-19/imunologia , SARS-CoV-2/imunologia , Vacinas Virais/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Linfócitos B/imunologia , Feminino , Imunogenicidade da Vacina/imunologia , Memória Imunológica/imunologia , Macaca mulatta , Masculino , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinação/métodosRESUMO
T cell-mediated immunity plays an important role in controlling SARS-CoV-2 infection, but the repertoire of naturally processed and presented viral epitopes on class I human leukocyte antigen (HLA-I) remains uncharacterized. Here, we report the first HLA-I immunopeptidome of SARS-CoV-2 in two cell lines at different times post infection using mass spectrometry. We found HLA-I peptides derived not only from canonical open reading frames (ORFs) but also from internal out-of-frame ORFs in spike and nucleocapsid not captured by current vaccines. Some peptides from out-of-frame ORFs elicited T cell responses in a humanized mouse model and individuals with COVID-19 that exceeded responses to canonical peptides, including some of the strongest epitopes reported to date. Whole-proteome analysis of infected cells revealed that early expressed viral proteins contribute more to HLA-I presentation and immunogenicity. These biological insights, as well as the discovery of out-of-frame ORF epitopes, will facilitate selection of peptides for immune monitoring and vaccine development.
Assuntos
Epitopos de Linfócito T/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Fases de Leitura Aberta/genética , Peptídeos/imunologia , Proteoma/imunologia , SARS-CoV-2/imunologia , Células A549 , Alelos , Sequência de Aminoácidos , Animais , Apresentação de Antígeno/imunologia , COVID-19/imunologia , COVID-19/virologia , Feminino , Células HEK293 , Humanos , Cinética , Masculino , Camundongos , Peptídeos/química , Linfócitos T/imunologiaRESUMO
The urgent need for an effective SARS-CoV-2 vaccine has forced development to progress in the absence of well-defined correlates of immunity. While neutralization has been linked to protection against other pathogens, whether neutralization alone will be sufficient to drive protection against SARS-CoV-2 in the broader population remains unclear. Therefore, to fully define protective humoral immunity, we dissected the early evolution of the humoral response in 193 hospitalized individuals ranging from moderate to severe. Although robust IgM and IgA responses evolved in both survivors and non-survivors with severe disease, non-survivors showed attenuated IgG responses, accompanied by compromised Fcɣ receptor binding and Fc effector activity, pointing to deficient humoral development rather than disease-enhancing humoral immunity. In contrast, individuals with moderate disease exhibited delayed responses that ultimately matured. These data highlight distinct humoral trajectories associated with resolution of SARS-CoV-2 infection and the need for early functional humoral immunity.
Assuntos
COVID-19 , Imunidade Humoral , Imunoglobulina A/imunologia , Imunoglobulina M/imunologia , Receptores de IgG/imunologia , SARS-CoV-2/imunologia , COVID-19/imunologia , COVID-19/mortalidade , Feminino , Células HL-60 , Humanos , MasculinoRESUMO
The COVID-19 pandemic has led to extensive morbidity and mortality throughout the world. Clinical features that drive SARS-CoV-2 pathogenesis in humans include inflammation and thrombosis, but the mechanistic details underlying these processes remain to be determined. In this study, we demonstrate endothelial disruption and vascular thrombosis in histopathologic sections of lungs from both humans and rhesus macaques infected with SARS-CoV-2. To define key molecular pathways associated with SARS-CoV-2 pathogenesis in macaques, we performed transcriptomic analyses of bronchoalveolar lavage and peripheral blood and proteomic analyses of serum. We observed macrophage infiltrates in lung and upregulation of macrophage, complement, platelet activation, thrombosis, and proinflammatory markers, including C-reactive protein, MX1, IL-6, IL-1, IL-8, TNFα, and NF-κB. These results suggest a model in which critical interactions between inflammatory and thrombosis pathways lead to SARS-CoV-2-induced vascular disease. Our findings suggest potential therapeutic targets for COVID-19.
Assuntos
COVID-19/complicações , COVID-19/imunologia , SARS-CoV-2/genética , Trombose/complicações , Doenças Vasculares/complicações , Idoso de 80 Anos ou mais , Animais , Lavagem Broncoalveolar , Proteína C-Reativa/análise , COVID-19/sangue , COVID-19/patologia , Ativação do Complemento , Citocinas/sangue , Feminino , Humanos , Inflamação/sangue , Inflamação/imunologia , Inflamação/virologia , Pulmão/patologia , Macaca mulatta , Macrófagos/imunologia , Masculino , Ativação Plaquetária , Trombose/sangue , Trombose/patologia , Transcriptoma , Doenças Vasculares/sangue , Doenças Vasculares/patologiaRESUMO
Several HIV-1 and SIV vaccine candidates have shown partial protection against viral challenges in rhesus macaques. However, the protective efficacy of vaccine-elicited polyclonal antibodies has not previously been demonstrated in adoptive transfer studies in nonhuman primates. In this study, we show that passive transfer of purified antibodies from vaccinated macaques can protect naive animals against SIVmac251 challenges. We vaccinated 30 rhesus macaques with Ad26-SIV Env/Gag/Pol and SIV Env gp140 protein vaccines and assessed the induction of antibody responses and a putative protective signature. This signature included multiple antibody functions and correlated with upregulation of interferon pathways in vaccinated animals. Adoptive transfer of purified immunoglobulin G (IgG) from the vaccinated animals with the most robust protective signatures provided partial protection against SIVmac251 challenges in naive recipient rhesus macaques. These data demonstrate the protective efficacy of purified vaccine-elicited antiviral antibodies in this model, even in the absence of virus neutralization.
Assuntos
Imunização Passiva/métodos , Vacinas contra a SAIDS/imunologia , Vírus da Imunodeficiência Símia/imunologia , Vacinas contra a AIDS/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Formação de Anticorpos/imunologia , Produtos do Gene env/imunologia , Produtos do Gene gag/imunologia , Produtos do Gene pol/imunologia , HIV-1/imunologia , Imunoglobulina G/imunologia , Macaca mulatta/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/imunologiaRESUMO
B cells constitute an essential line of defense from pathogenic infections through the generation of class-switched antibody-secreting cells (ASCs) in germinal centers. Although this process is known to be regulated by follicular helper T (TfH) cells, the mechanism by which B cells initially seed germinal center reactions remains elusive. We found that NKT cells, a population of innate-like T lymphocytes, are critical for the induction of B cell immunity upon viral infection. The positioning of NKT cells at the interfollicular areas of lymph nodes facilitates both their direct priming by resident macrophages and the localized delivery of innate signals to antigen-experienced B cells. Indeed, NKT cells secrete an early wave of IL-4 and constitute up to 70% of the total IL-4-producing cells during the initial stages of infection. Importantly, the requirement of this innate immunity arm appears to be evolutionarily conserved because early NKT and IL-4 gene signatures also positively correlate with the levels of neutralizing antibodies in Zika-virus-infected macaques. In conclusion, our data support a model wherein a pre-TfH wave of IL-4 secreted by interfollicular NKT cells triggers the seeding of germinal center cells and serves as an innate link between viral infection and B cell immunity.
Assuntos
Linfócitos B/imunologia , Centro Germinativo/imunologia , Imunidade Inata , Influenza Humana/imunologia , Interleucina-4/genética , Células Matadoras Naturais/imunologia , Infecção por Zika virus/imunologia , Animais , Galinhas , Cães , Centro Germinativo/citologia , Humanos , Interleucina-4/metabolismo , Macaca , Macrófagos/imunologia , Células Madin Darby de Rim Canino , Camundongos , Camundongos Endogâmicos C57BLRESUMO
The development of interventions to prevent congenital Zika syndrome (CZS) has been limited by the lack of an established nonhuman primate model. Here we show that infection of female rhesus monkeys early in pregnancy with Zika virus (ZIKV) recapitulates many features of CZS in humans. We infected 9 pregnant monkeys with ZIKV, 6 early in pregnancy (weeks 6-7 of gestation) and 3 later in pregnancy (weeks 12-14 of gestation), and compared findings with uninfected controls. 100% (6 of 6) of monkeys infected early in pregnancy exhibited prolonged maternal viremia and fetal neuropathology, including fetal loss, smaller brain size, and histopathologic brain lesions, including microcalcifications, hemorrhage, necrosis, vasculitis, gliosis, and apoptosis of neuroprogenitor cells. High-resolution MRI demonstrated concordant lesions indicative of deep gray matter injury. We also observed spinal, ocular, and neuromuscular pathology. Our data show that vascular compromise and neuroprogenitor cell dysfunction are hallmarks of CZS pathogenesis, suggesting novel strategies to prevent and to treat this disease.
Assuntos
Feto/virologia , Neurônios/patologia , Infecção por Zika virus/patologia , Zika virus/patogenicidade , Animais , Animais Recém-Nascidos , Apoptose , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Calcinose/patologia , Calcinose/veterinária , Feminino , Idade Gestacional , Macaca mulatta , Imageamento por Ressonância Magnética , Necrose , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Células-Tronco Neurais/virologia , Neurônios/virologia , Gravidez , Índice de Gravidade de Doença , Vasculite/patologia , Vasculite/veterinária , Infecção por Zika virus/veterinária , Infecção por Zika virus/virologiaRESUMO
Zika virus (ZIKV) is associated with severe neuropathology in neonates as well as Guillain-Barré syndrome and other neurologic disorders in adults. Prolonged viral shedding has been reported in semen, suggesting the presence of anatomic viral reservoirs. Here we show that ZIKV can persist in cerebrospinal fluid (CSF) and lymph nodes (LN) of infected rhesus monkeys for weeks after virus has been cleared from peripheral blood, urine, and mucosal secretions. ZIKV-specific neutralizing antibodies correlated with rapid clearance of virus in peripheral blood but remained undetectable in CSF for the duration of the study. Viral persistence in both CSF and LN correlated with upregulation of mechanistic target of rapamycin (mTOR), proinflammatory, and anti-apoptotic signaling pathways, as well as downregulation of extracellular matrix signaling pathways. These data raise the possibility that persistent or occult neurologic and lymphoid disease may occur following clearance of peripheral virus in ZIKV-infected individuals.
Assuntos
Infecção por Zika virus/imunologia , Infecção por Zika virus/virologia , Animais , Líquido Cefalorraquidiano/virologia , Inflamação/imunologia , Trato Gastrointestinal Inferior/virologia , Linfonodos/virologia , Macaca mulatta , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismoRESUMO
The earliest events following mucosal HIV-1 infection, prior to measurable viremia, remain poorly understood. Here, by detailed necropsy studies, we show that the virus can rapidly disseminate following mucosal SIV infection of rhesus monkeys and trigger components of the inflammasome, both at the site of inoculation and at early sites of distal virus spread. By 24 hr following inoculation, a proinflammatory signature that lacked antiviral restriction factors was observed in viral RNA-positive tissues. The early innate response included expression of NLRX1, which inhibits antiviral responses, and activation of the TGF-ß pathway, which negatively regulates adaptive immune responses. These data suggest a model in which the virus triggers specific host mechanisms that suppress the generation of antiviral innate and adaptive immune responses in the first few days of infection, thus facilitating its own replication. These findings have important implications for the development of vaccines and other strategies to prevent infection.
Assuntos
Inflamassomos/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Vírus da Imunodeficiência Símia/fisiologia , Animais , Medula Óssea/imunologia , Imunidade Inata , Imunidade nas Mucosas , Células Matadoras Naturais/imunologia , Macaca mulatta , Proteínas Mitocondriais/metabolismo , Monócitos/imunologia , Linfócitos T/imunologia , Transcriptoma , Fator de Crescimento Transformador beta/metabolismo , Replicação ViralRESUMO
Wu et al. couple next-generation sequencing with structural analysis to illuminate the key processes that enable the natural evolution and selection of broadly neutralizing antibodies to HIV-1, providing a potential roadmap for the development of HIV-1 vaccine strategies to accelerate the induction of protective antibodies.
Assuntos
Anticorpos Neutralizantes/genética , Linfócitos B/imunologia , Evolução Molecular , Infecções por HIV/imunologia , HIV-1/imunologia , HumanosRESUMO
While antibody titers and neutralization are considered the gold standard for the selection of successful vaccines, these parameters are often inadequate predictors of protective immunity. As antibodies mediate an array of extra-neutralizing Fc functions, when neutralization fails to predict protection, investigating Fc-mediated activity may help identify immunological correlates and mechanism(s) of humoral protection. Here, we used an integrative approach termed Systems Serology to analyze relationships among humoral responses elicited in four HIV vaccine trials. Each vaccine regimen induced a unique humoral "Fc fingerprint." Moreover, analysis of case:control data from the first moderately protective HIV vaccine trial, RV144, pointed to mechanistic insights into immune complex composition that may underlie protective immunity to HIV. Thus, multi-dimensional relational comparisons of vaccine humoral fingerprints offer a unique approach for the evaluation and design of novel vaccines against pathogens for which correlates of protection remain elusive.
Assuntos
Vacinas contra a AIDS/imunologia , Anticorpos Antivirais/imunologia , Imunoglobulina G/imunologia , Animais , Anticorpos Antivirais/sangue , Citotoxicidade Celular Dependente de Anticorpos , Complexo Antígeno-Anticorpo/imunologia , Ensaios Clínicos como Assunto , Desenho de Fármacos , Infecções por HIV/imunologia , Humanos , Imunoglobulina G/sangue , Receptores Fc/imunologiaRESUMO
A limitation of current SARS-CoV-2 vaccines is that they provide minimal protection against infection with current Omicron subvariants1,2, although they still provide protection against severe disease. Enhanced mucosal immunity may be required to block infection and onward transmission. Intranasal administration of current vaccines has proven inconsistent3-7, suggesting that alternative immunization strategies may be required. Here we show that intratracheal boosting with a bivalent Ad26-based SARS-CoV-2 vaccine results in substantial induction of mucosal humoral and cellular immunity and near-complete protection against SARS-CoV-2 BQ.1.1 challenge. A total of 40 previously immunized rhesus macaques were boosted with a bivalent Ad26 vaccine by the intramuscular, intranasal and intratracheal routes, or with a bivalent mRNA vaccine by the intranasal route. Ad26 boosting by the intratracheal route led to a substantial expansion of mucosal neutralizing antibodies, IgG and IgA binding antibodies, and CD8+ and CD4+ T cell responses, which exceeded those induced by Ad26 boosting by the intramuscular and intranasal routes. Intratracheal Ad26 boosting also led to robust upregulation of cytokine, natural killer, and T and B cell pathways in the lungs. After challenge with a high dose of SARS-CoV-2 BQ.1.1, intratracheal Ad26 boosting provided near-complete protection, whereas the other boosting strategies proved less effective. Protective efficacy correlated best with mucosal humoral and cellular immune responses. These data demonstrate that these immunization strategies induce robust mucosal immunity, suggesting the feasibility of developing vaccines that block respiratory viral infections.
Assuntos
Vacinas contra COVID-19 , COVID-19 , Imunidade nas Mucosas , Imunização Secundária , Macaca mulatta , SARS-CoV-2 , Animais , Humanos , Administração Intranasal , Anticorpos Neutralizantes/biossíntese , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/biossíntese , Anticorpos Antivirais/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , COVID-19/imunologia , COVID-19/prevenção & controle , COVID-19/virologia , Vacinas contra COVID-19/administração & dosagem , Vacinas contra COVID-19/imunologia , Citocinas/imunologia , Imunidade nas Mucosas/imunologia , Imunização Secundária/métodos , Imunoglobulina A/imunologia , Imunoglobulina G/imunologia , Injeções Intramusculares , Células Matadoras Naturais/imunologia , Pulmão/imunologia , Macaca mulatta/imunologia , Macaca mulatta/virologia , Vacinas de mRNA/administração & dosagem , Vacinas de mRNA/imunologia , SARS-CoV-2/classificação , SARS-CoV-2/imunologia , Traqueia/imunologia , Traqueia/virologiaRESUMO
Despite major advances in HIV-1 therapeutics and prevention strategies, the development of a safe and effective prophylactic HIV-1 vaccine will likely be critical for ending the global HIV-1 epidemic. Yet only four HIV-1 vaccine concepts have been tested for clinical efficacy over the past 30 years. In this Commentary, we describe key hurdles facing the HIV-1 vaccine development field and outline strategies to accelerate efficacy evaluation of novel HIV-1 vaccine candidates.
Assuntos
Vacinas contra a AIDS/uso terapêutico , Ensaios Clínicos como Assunto , HIV-1/fisiologia , Pesquisa Biomédica/economia , Ensaios Clínicos como Assunto/economia , Feminino , Infecções por HIV/prevenção & controle , Infecções por HIV/virologia , HIV-1/genética , Humanos , MasculinoRESUMO
Passive administration of HIV neutralizing antibodies (nAbs) can protect macaques from hard-to-neutralize (tier 2) chimeric simian-human immunodeficiency virus (SHIV) challenge. However, conditions for nAb-mediated protection after vaccination have not been established. Here, we selected groups of 6 rhesus macaques with either high or low serum nAb titers from a total of 78 animals immunized with recombinant native-like (SOSIP) Env trimers. Repeat intrarectal challenge with homologous tier 2 SHIVBG505 led to rapid infection in unimmunized and low-titer animals. High-titer animals, however, demonstrated protection that was gradually lost as nAb titers waned over time. An autologous serum ID50 nAb titer of â¼1:500 afforded more than 90% protection from medium-dose SHIV infection. In contrast, antibody-dependent cellular cytotoxicity and T cell activity did not correlate with protection. Therefore, Env protein-based vaccination strategies can protect against hard-to-neutralize SHIV challenge in rhesus macaques by inducing tier 2 nAbs, provided appropriate neutralizing titers can be reached and maintained.
Assuntos
Vacinas contra a AIDS/imunologia , Anticorpos Anti-HIV/imunologia , Infecções por HIV/imunologia , HIV/fisiologia , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Vírus da Imunodeficiência Símia/fisiologia , Produtos do Gene env do Vírus da Imunodeficiência Humana/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Humanos , Macaca mulatta , VacinaçãoRESUMO
The global diversity of HIV-1 represents a critical challenge facing HIV-1 vaccine development. HIV-1 mosaic antigens are bioinformatically optimized immunogens designed for improved coverage of HIV-1 diversity. However, the protective efficacy of such global HIV-1 vaccine antigens has not previously been evaluated. Here, we demonstrate the capacity of bivalent HIV-1 mosaic antigens to protect rhesus monkeys against acquisition of infection following heterologous challenges with the difficult-to-neutralize simian-human immunodeficiency virus SHIV-SF162P3. Adenovirus/poxvirus and adenovirus/adenovirus vector-based vaccines expressing HIV-1 mosaic Env, Gag, and Pol afforded a significant reduction in the per-exposure acquisition risk following repetitive, intrarectal SHIV-SF162P3 challenges. Protection against acquisition of infection correlated with vaccine-elicited binding, neutralizing, and functional nonneutralizing antibodies, suggesting that the coordinated activity of multiple antibody functions may contribute to protection against difficult-to-neutralize viruses. These data demonstrate the protective efficacy of HIV-1 mosaic antigens and suggest a potential strategy for the development of a global HIV-1 vaccine. PAPERCLIP:
Assuntos
Vacinas contra a AIDS/imunologia , HIV-1 , Animais , Formação de Anticorpos , Feminino , Antígenos HIV/imunologia , Proteínas do Vírus da Imunodeficiência Humana/imunologia , Imunidade Celular , Macaca mulatta , Masculino , Dados de Sequência Molecular , Organismos Livres de Patógenos EspecíficosRESUMO
The highly mutated SARS-CoV-2 Omicron (B.1.1.529) variant has been shown to evade a substantial fraction of neutralizing antibody responses elicited by current vaccines that encode the WA1/2020 spike protein1. Cellular immune responses, particularly CD8+ T cell responses, probably contribute to protection against severe SARS-CoV-2 infection2-6. Here we show that cellular immunity induced by current vaccines against SARS-CoV-2 is highly conserved to the SARS-CoV-2 Omicron spike protein. Individuals who received the Ad26.COV2.S or BNT162b2 vaccines demonstrated durable spike-specific CD8+ and CD4+ T cell responses, which showed extensive cross-reactivity against both the Delta and the Omicron variants, including in central and effector memory cellular subpopulations. Median Omicron spike-specific CD8+ T cell responses were 82-84% of the WA1/2020 spike-specific CD8+ T cell responses. These data provide immunological context for the observation that current vaccines still show robust protection against severe disease with the SARS-CoV-2 Omicron variant despite the substantially reduced neutralizing antibody responses7,8.