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1.
Proc Natl Acad Sci U S A ; 118(38)2021 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-34470866

RESUMO

Emergence of novel variants of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) underscores the need for next-generation vaccines able to elicit broad and durable immunity. Here we report the evaluation of a ferritin nanoparticle vaccine displaying the receptor-binding domain of the SARS-CoV-2 spike protein (RFN) adjuvanted with Army Liposomal Formulation QS-21 (ALFQ). RFN vaccination of macaques using a two-dose regimen resulted in robust, predominantly Th1 CD4+ T cell responses and reciprocal peak mean serum neutralizing antibody titers of 14,000 to 21,000. Rapid control of viral replication was achieved in the upper and lower airways of animals after high-dose SARS-CoV-2 respiratory challenge, with undetectable replication within 4 d in seven of eight animals receiving 50 µg of RFN. Cross-neutralization activity against SARS-CoV-2 variant B.1.351 decreased only approximately twofold relative to WA1/2020. In addition, neutralizing, effector antibody and cellular responses targeted the heterotypic SARS-CoV-1, highlighting the broad immunogenicity of RFN-ALFQ for SARS-CoV-like Sarbecovirus vaccine development.


Assuntos
Vacinas contra COVID-19/administração & dosagem , COVID-19/virologia , Macaca mulatta/imunologia , Nanopartículas/química , Receptores Virais/metabolismo , SARS-CoV-2/imunologia , Adjuvantes Imunológicos/administração & dosagem , Animais , Anticorpos Neutralizantes/biossíntese , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/biossíntese , Anticorpos Antivirais/imunologia , COVID-19/prevenção & controle , Vacinas contra COVID-19/imunologia , Ferritinas/química , SARS-CoV-2/metabolismo , Linfócitos T/imunologia
2.
Science ; 373(6561): eabj0299, 2021 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-34529476
3.
Neuron ; 109(18): 2995-3011.e5, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34534456

RESUMO

The theory of predictive processing posits that the brain computes expectations to process information predictively. Empirical evidence in support of this theory, however, is scarce and largely limited to sensory areas. Here, we report a precise and adaptive mechanism in the frontal cortex of non-human primates consistent with predictive processing of temporal events. We found that the speed of neural dynamics is precisely adjusted according to the average time of an expected stimulus. This speed adjustment, in turn, enables neurons to encode stimuli in terms of deviations from expectation. This lawful relationship was evident across multiple experiments and held true during learning: when temporal statistics underwent covert changes, neural responses underwent predictable changes that reflected the new mean. Together, these results highlight a precise mathematical relationship between temporal statistics in the environment and neural activity in the frontal cortex that may serve as a mechanism for predictive temporal processing.


Assuntos
Adaptação Fisiológica/fisiologia , Lobo Frontal/fisiologia , Neurônios/fisiologia , Estimulação Luminosa/métodos , Percepção do Tempo/fisiologia , Animais , Previsões , Macaca mulatta , Masculino
4.
Signal Transduct Target Ther ; 6(1): 328, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34471088

RESUMO

Understanding the pathological features of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in an animal model is crucial for the treatment of coronavirus disease 2019 (COVID-19). Here, we compared immunopathological changes in young and old rhesus macaques (RMs) before and after SARS-CoV-2 infection at the tissue level. Quantitative analysis of multiplex immunofluorescence staining images of formalin-fixed paraffin-embedded (FFPE) sections showed that SARS-CoV-2 infection specifically induced elevated levels of apoptosis, autophagy, and nuclear factor kappa-B (NF-κB) activation of angiotensin-converting enzyme 2 (ACE2)+ cells, and increased interferon α (IFN-α)- and interleukin 6 (IL-6)-secreting cells and C-X-C motif chemokine receptor 3 (CXCR3)+ cells in lung tissue of old RMs. This pathological pattern, which may be related to the age-related pro-inflammatory microenvironment in both lungs and spleens, was significantly correlated with the systemic accumulation of CXCR3+ cells in lungs, spleens, and peripheral blood. Furthermore, the ratio of CXCR3+ to T-box protein expression in T cell (T-bet)+ (CXCR3+/T-bet+ ratio) in CD8+ cells may be used as a predictor of severe COVID-19. These findings uncovered the impact of aging on the immunopathology of early SARS-CoV-2 infection and demonstrated the potential application of CXCR3+ cells in predicting severe COVID-19.


Assuntos
Linfócitos T CD8-Positivos/imunologia , COVID-19/imunologia , Microambiente Celular/imunologia , Pulmão/imunologia , Receptores CXCR3/imunologia , SARS-CoV-2/imunologia , Enzima de Conversão de Angiotensina 2/imunologia , Animais , Linfócitos T CD8-Positivos/patologia , COVID-19/patologia , Modelos Animais de Doenças , Inflamação/imunologia , Inflamação/patologia , Interferon-alfa/imunologia , Interleucina-6/imunologia , Pulmão/patologia , Pulmão/virologia , Macaca mulatta , Masculino
6.
PLoS Pathog ; 17(9): e1009701, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34551020

RESUMO

The speed of development, versatility and efficacy of mRNA-based vaccines have been amply demonstrated in the case of SARS-CoV-2. DNA vaccines represent an important alternative since they induce both humoral and cellular immune responses in animal models and in human trials. We tested the immunogenicity and protective efficacy of DNA-based vaccine regimens expressing different prefusion-stabilized Wuhan-Hu-1 SARS-CoV-2 Spike antigens upon intramuscular injection followed by electroporation in rhesus macaques. Different Spike DNA vaccine regimens induced antibodies that potently neutralized SARS-CoV-2 in vitro and elicited robust T cell responses. The antibodies recognized and potently neutralized a panel of different Spike variants including Alpha, Delta, Epsilon, Eta and A.23.1, but to a lesser extent Beta and Gamma. The DNA-only vaccine regimens were compared to a regimen that included co-immunization of Spike DNA and protein in the same anatomical site, the latter of which showed significant higher antibody responses. All vaccine regimens led to control of SARS-CoV-2 intranasal/intratracheal challenge and absence of virus dissemination to the lower respiratory tract. Vaccine-induced binding and neutralizing antibody titers and antibody-dependent cellular phagocytosis inversely correlated with transient virus levels in the nasal mucosa. Importantly, the Spike DNA+Protein co-immunization regimen induced the highest binding and neutralizing antibodies and showed the strongest control against SARS-CoV-2 challenge in rhesus macaques.


Assuntos
Macaca mulatta , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinas de DNA , Animais , COVID-19/imunologia , COVID-19/terapia , Estudos de Coortes , DNA Viral/imunologia , Modelos Animais de Doenças , Feminino , Imunização Passiva , Leucócitos Mononucleares/imunologia , Camundongos , RNA Mensageiro/análise , SARS-CoV-2/genética , Linfócitos T/imunologia , Vacinas de DNA/administração & dosagem , Vacinas de DNA/imunologia
7.
Viruses ; 13(8)2021 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-34452537

RESUMO

The post-acute phase of SARS-CoV-2 infection was investigated in rhesus (Macaca mulatta) and cynomolgus macaques (Macaca fascicularis). During the acute phase of infection, SARS-CoV-2 was shed via the nose and throat, and viral RNA was occasionally detected in feces. This phase coincided with a transient change in systemic immune activation. Even after the alleged resolution of the infection, computed tomography (CT) and positron emission tomography (PET)-CT revealed pulmonary lesions and activated tracheobronchial lymph nodes in all animals. Post-mortem histological examination of the lung tissue revealed mostly marginal or resolving minimal lesions that were indicative of SARS-CoV-2 infection. Evidence for SARS-CoV-2-induced histopathology was also found in extrapulmonary tissue samples, such as conjunctiva, cervical, and mesenteric lymph nodes. However, 5-6 weeks after SARS-CoV-2 exposure, upon necropsy, viral RNA was still detectable in a wide range of tissue samples in 50% of the macaques and included amongst others the heart, the respiratory tract and surrounding lymph nodes, salivary gland, and conjunctiva. Subgenomic messenger RNA was detected in the lungs and tracheobronchial lymph nodes, indicative of ongoing virus replication during the post-acute phase. These results could be relevant for understanding the long-term consequences of COVID-19 in humans.


Assuntos
COVID-19/patologia , COVID-19/virologia , Pulmão/patologia , SARS-CoV-2/fisiologia , Animais , Anticorpos Antivirais/sangue , COVID-19/imunologia , Citocinas/sangue , Modelos Animais de Doenças , Humanos , Pulmão/virologia , Linfonodos/patologia , Linfonodos/fisiopatologia , Macaca fascicularis , Macaca mulatta , RNA Mensageiro/análise , RNA Viral/análise , Sistema Respiratório/patologia , Sistema Respiratório/virologia , SARS-CoV-2/imunologia , Replicação Viral
8.
FASEB J ; 35(9): e21798, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34339064

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic threatens human species with mortality rate of roughly 2%. We can hardly predict the time of herd immunity against and end of COVID-19 with or without success of vaccine. One way to overcome the situation is to define what delineates disease severity and serves as a molecular target. The most successful analogy is found in BCR-ABL in chronic myeloid leukemia, which is the golden biomarker, and simultaneously, the most effective molecular target. We hypothesize that S100 calcium-binding protein A8 (S100A8) is one such molecule. The underlying evidence includes accumulating clinical information that S100A8 is upregulated in severe forms of COVID-19, pathological similarities of the affected lungs between COVID-19 and S100A8-induced acute respiratory distress syndrome (ARDS) model, homeostatic inflammation theory in which S100A8 is an endogenous ligand for endotoxin sensor Toll-like receptor 4/Myeloid differentiation protein-2 (TLR4/MD-2) and mediates hyper-inflammation even after elimination of endotoxin-producing extrinsic pathogens, analogous findings between COVID-19-associated ARDS and pre-metastatic lungs such as S100A8 upregulation, pulmonary recruitment of myeloid cells, increased vascular permeability, and activation coagulation cascade. A successful treatment in an animal COVID-19 model is given with a reagent capable of abrogating interaction between S100A8/S100A9 and TLR4. In this paper, we try to verify our hypothesis that S100A8 governs COVID-19-associated ARDS.


Assuntos
COVID-19/complicações , Calgranulina A/fisiologia , Síndrome da Liberação de Citocina/etiologia , Inflamação/etiologia , Pandemias , Síndrome do Desconforto Respiratório/etiologia , SARS-CoV-2/genética , Enzima de Conversão de Angiotensina 2/genética , Enzima de Conversão de Angiotensina 2/fisiologia , Animais , Antivirais/farmacologia , COVID-19/genética , COVID-19/patologia , Calgranulina A/sangue , Calgranulina A/genética , Quimiocina CXCL11/sangue , Síndrome da Liberação de Citocina/genética , Síndrome da Liberação de Citocina/patologia , Dissacarídeos/farmacologia , Dissacarídeos/uso terapêutico , Modelos Animais de Doenças , Descoberta de Drogas , Células Epiteliais/metabolismo , Células Epiteliais/virologia , Humanos , Inflamação/genética , Inflamação/patologia , Pulmão/metabolismo , Pulmão/patologia , Pulmão/virologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/secundário , Antígeno 96 de Linfócito/fisiologia , Macaca mulatta , Camundongos , Camundongos Transgênicos , Modelos Biológicos , Mutação , Síndrome do Desconforto Respiratório/genética , Síndrome do Desconforto Respiratório/metabolismo , Especificidade da Espécie , Fosfatos Açúcares/farmacologia , Fosfatos Açúcares/uso terapêutico , Receptor 4 Toll-Like/fisiologia , Regulação para Cima , Internalização do Vírus
9.
Sci Transl Med ; 13(607)2021 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-34408080

RESUMO

Anti-HIV broadly neutralizing antibodies (bNAbs) may favor development of antiviral immunity by engaging the immune system during immunotherapy. Targeting integrin α4ß7 with an anti-α4ß7 monoclonal antibody (Rh-α4ß7) affects immune responses in SIV/SHIV-infected macaques. To explore the therapeutic potential of combining bNAbs with α4ß7 integrin blockade, SHIVSF162P3-infected, viremic rhesus macaques were treated with bNAbs only (VRC07-523LS and PGT128 anti-HIV antibodies) or a combination of bNAbs and Rh-α4ß7 or were left untreated as a control. Treatment with bNAbs alone decreased viremia below 200 copies/ml in all macaques, but seven of eight macaques (87.5%) in the bNAbs-only group rebounded within a median of 3 weeks (95% CI: 2 to 9). In contrast, three of six macaques treated with a combination of Rh-α4ß7 and bNAbs (50%) maintained a viremia below 200 copies/ml until the end of the follow-up period; viremia in the other three macaques rebounded within a median of 6 weeks (95% CI: 5 to 11). Thus, there was a modest delay in viral rebound in the macaques treated with the combination antibody therapy compared to bNAbs alone. Our study suggests that α4ß7 integrin blockade may prolong virologic control by bNAbs in SHIVSF162P3-infected macaques.


Assuntos
Infecções por HIV , HIV-1 , Síndrome de Imunodeficiência Adquirida dos Símios , Vírus da Imunodeficiência Símia , Animais , Anticorpos Neutralizantes , Anticorpos Antivirais , Anticorpos Amplamente Neutralizantes , Anticorpos Anti-HIV , Infecções por HIV/tratamento farmacológico , Integrinas , Macaca mulatta , Síndrome de Imunodeficiência Adquirida dos Símios/tratamento farmacológico
10.
Cell Host Microbe ; 29(9): 1437-1453.e8, 2021 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-34428428

RESUMO

The SARS-CoV-2 pandemic has affected more than 185 million people worldwide resulting in over 4 million deaths. To contain the pandemic, there is a continued need for safe vaccines that provide durable protection at low and scalable doses and can be deployed easily. Here, AAVCOVID-1, an adeno-associated viral (AAV), spike-gene-based vaccine candidate demonstrates potent immunogenicity in mouse and non-human primates following a single injection and confers complete protection from SARS-CoV-2 challenge in macaques. Peak neutralizing antibody titers are sustained at 1 year and complemented by functional memory T cell responses. The AAVCOVID vector has no relevant pre-existing immunity in humans and does not elicit cross-reactivity to common AAVs used in gene therapy. Vector genome persistence and expression wanes following injection. The single low-dose requirement, high-yield manufacturability, and 1-month stability for storage at room temperature may make this technology well suited to support effective immunization campaigns for emerging pathogens on a global scale.


Assuntos
Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Vacinas contra COVID-19/imunologia , COVID-19/prevenção & controle , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Vacinas contra COVID-19/administração & dosagem , Vacinas contra COVID-19/genética , Dependovirus/genética , Dependovirus/metabolismo , Feminino , Humanos , Imunogenicidade da Vacina/imunologia , Memória Imunológica/imunologia , Macaca fascicularis , Macaca mulatta , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Linfócitos T/imunologia , Transgenes/genética , Vacinação/métodos , Carga Viral/imunologia
11.
Biomolecules ; 11(8)2021 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-34439830

RESUMO

BACKGROUND: Animal and clinical studies have shown that remote ischemic conditioning (RIC) has protective effects for cerebral vascular diseases, with induced humoral factor changes in the peripheral blood. However, many findings are heterogeneous, perhaps due to differences in the RIC intervention schemes, enrolled populations, and sample times. This study aimed to examine the RIC-induced changes in the plasma proteome using rhesus monkey models of strokes. METHODS: Two adult rhesus monkeys with autologous blood clot-induced middle cerebral artery (MCA) occlusion underwent RIC interventions twice a week for five consecutive weeks. Each RIC treatment included five cycles of five minutes of ischemia alternating with five minutes of reperfusion of the forearm. The blood samples were taken from the median cubital vein of the monkeys at baseline and immediately after each week's RIC stimulus. The plasma samples were isolated for a proteomic analysis using mass spectrometry (MS). RESULTS: Several proteins related to lipid metabolism (Apolipoprotein A-II and Apolipoprotein C-II), coagulation (Fibrinogen alpha chain and serpin), immunoinflammatory responses (complement C3 and C1), and endovascular hemostasis (basement membrane-specific heparan sulfate proteoglycan) were significantly modulated after the RIC intervention. Many of these induced changes, such as in the lipid metabolism regulation and anticoagulation responses, starting as early as two weeks following the RIC intervention. The complementary activation and protection of the endovascular cells occurred more than three weeks postintervention. CONCLUSIONS: Multiple protective effects were induced by RIC and involved lipid metabolism regulation (anti-atherogenesis), anticoagulation (antithrombosis), complement activation, and endovascular homeostasis (anti-inflammation). In conclusion, this study indicates that RIC results in significant modulations of the plasma proteome. It also provides ideas for future research and screening targets.


Assuntos
Proteínas Sanguíneas/metabolismo , Isquemia Encefálica/sangue , Isquemia Encefálica/veterinária , Pós-Condicionamento Isquêmico/métodos , AVC Isquêmico/sangue , AVC Isquêmico/veterinária , Animais , Proteínas Sanguíneas/classificação , Isquemia Encefálica/fisiopatologia , Isquemia Encefálica/terapia , Cromatografia Líquida , Modelos Animais de Doenças , Ontologia Genética , Humanos , Infarto da Artéria Cerebral Média/cirurgia , AVC Isquêmico/fisiopatologia , AVC Isquêmico/terapia , Macaca mulatta , Masculino , Anotação de Sequência Molecular , Proteômica/métodos , Espectrometria de Massas em Tandem
12.
Nat Methods ; 18(9): 1112-1116, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34462591

RESUMO

Optogenetic methods have been widely used in rodent brains, but remain relatively under-developed for nonhuman primates such as rhesus macaques, an animal model with a large brain expressing sophisticated sensory, motor and cognitive behaviors. To address challenges in behavioral optogenetics in large brains, we developed Opto-Array, a chronically implantable array of light-emitting diodes for high-throughput optogenetic perturbation. We demonstrated that optogenetic silencing in the macaque primary visual cortex with the help of the Opto-Array results in reliable retinotopic visual deficits in a luminance discrimination task. We separately confirmed that Opto-Array illumination results in local neural silencing, and that behavioral effects are not due to tissue heating. These results demonstrate the effectiveness of the Opto-Array for behavioral optogenetic applications in large brains.


Assuntos
Encéfalo/fisiologia , Optogenética/métodos , Próteses e Implantes , Animais , Comportamento Animal , Eletrônica/métodos , Tecnologia de Fibra Óptica , Macaca mulatta , Masculino , Córtex Visual
13.
Nat Rev Neurosci ; 22(9): 573-583, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34345018

RESUMO

How does the brain encode information about the environment? Decades of research have led to the pervasive notion that the object-processing pathway in primate cortex consists of multiple areas that are each specialized to process different object categories (such as faces, bodies, hands, non-face objects and scenes). The anatomical consistency and modularity of these regions have been interpreted as evidence that these regions are innately specialized. Here, we propose that ventral-stream modules do not represent clusters of circuits that each evolved to process some specific object category particularly important for survival, but instead reflect the effects of experience on a domain-general architecture that evolved to be able to adapt, within a lifetime, to its particular environment. Furthermore, we propose that the mechanisms underlying the development of domains are both evolutionarily old and universal across cortex. Topographic maps are fundamental, governing the development of specializations across systems, providing a framework for brain organization.


Assuntos
Lobo Temporal/fisiologia , Vias Visuais/fisiologia , Animais , Mapeamento Encefálico , Humanos , Macaca mulatta , Neurônios/fisiologia , Estimulação Luminosa , Percepção Visual/fisiologia
15.
Life Sci Alliance ; 4(10)2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34344719

RESUMO

The duration of viral shedding is determined by a balance between de novo infection and removal of infected cells. That is, if infection is completely blocked with antiviral drugs (100% inhibition), the duration of viral shedding is minimal and is determined by the length of virus production. However, some mathematical models predict that if infected individuals are treated with antiviral drugs with efficacy below 100%, viral shedding may last longer than without treatment because further de novo infections are driven by entry of the virus into partially protected, uninfected cells at a slower rate. Using a simple mathematical model, we quantified SARS-CoV-2 infection dynamics in non-human primates and characterized the kinetics of viral shedding. We counterintuitively found that treatments initiated early, such as 0.5 d after virus inoculation, with intermediate to relatively high efficacy (30-70% inhibition of virus replication) yield a prolonged duration of viral shedding (by about 6.0 d) compared with no treatment.


Assuntos
Antivirais/farmacologia , COVID-19/tratamento farmacológico , COVID-19/virologia , Eliminação de Partículas Virais/efeitos dos fármacos , Monofosfato de Adenosina/análogos & derivados , Monofosfato de Adenosina/farmacologia , Alanina/análogos & derivados , Alanina/farmacologia , Animais , Pulmão/virologia , Macaca mulatta , Modelos Teóricos , Nariz/virologia , Faringe/virologia , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/fisiologia , Fatores de Tempo , Carga Viral/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos
16.
Int J Mol Sci ; 22(15)2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34360852

RESUMO

Fluoxetine is an antidepressant commonly prescribed not only to adults but also to children for the treatment of depression, obsessive-compulsive disorder, and neurodevelopmental disorders. The adverse effects of the long-term treatment reported in some patients, especially in younger individuals, call for a detailed investigation of molecular alterations induced by fluoxetine treatment. Two-year fluoxetine administration to juvenile macaques revealed effects on impulsivity, sleep, social interaction, and peripheral metabolites. Here, we built upon this work by assessing residual effects of fluoxetine administration on the expression of genes and abundance of lipids and polar metabolites in the prelimbic cortex of 10 treated and 11 control macaques representing two monoamine oxidase A (MAOA) genotypes. Analysis of 8871 mRNA transcripts, 3608 lipids, and 1829 polar metabolites revealed substantial alterations of the brain lipid content, including significant abundance changes of 106 lipid features, accompanied by subtle changes in gene expression. Lipid alterations in the drug-treated animals were most evident for polyunsaturated fatty acids (PUFAs). A decrease in PUFAs levels was observed in all quantified lipid classes excluding sphingolipids, which do not usually contain PUFAs, suggesting systemic changes in fatty acid metabolism. Furthermore, the residual effect of the drug on lipid abundances was more pronounced in macaques carrying the MAOA-L genotype, mirroring reported behavioral effects of the treatment. We speculate that a decrease in PUFAs may be associated with adverse effects in depressive patients and could potentially account for the variation in individual response to fluoxetine in young people.


Assuntos
Antidepressivos/efeitos adversos , Comportamento Animal/efeitos dos fármacos , Fluoxetina/efeitos adversos , Metabolismo dos Lipídeos/efeitos dos fármacos , Transtornos Mentais/tratamento farmacológico , Animais , Ácidos Graxos Insaturados/metabolismo , Macaca mulatta , Masculino
17.
Viruses ; 13(8)2021 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-34452509

RESUMO

Many different vaccine candidates against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the etiological agent of COVID-19, are currently approved and under development. Vaccine platforms vary from mRNA vaccines to viral-vectored vaccines, and several candidates have been shown to produce humoral and cellular responses in small animal models, non-human primates, and human volunteers. In this study, six non-human primates received a prime-boost intramuscular vaccination with 4 µg of mRNA vaccine candidate CV07050101, which encodes a pre-fusion stabilized spike (S) protein of SARS-CoV-2. Boost vaccination was performed 28 days post prime vaccination. As a control, six animals were similarly injected with PBS. Humoral and cellular immune responses were investigated at time of vaccination, and two weeks afterwards. No antibodies could be detected at two and four weeks after prime vaccination. Two weeks after boost vaccination, binding but no neutralizing antibodies were detected in four out of six non-human primates. SARS-CoV-2 S protein-specific T cell responses were detected in these four animals. In conclusion, prime-boost vaccination with 4 µg of vaccine candidate CV07050101 resulted in limited immune responses in four out of six non-human primates.


Assuntos
Anticorpos Antivirais/sangue , Vacinas contra COVID-19/imunologia , Imunização Secundária , Imunogenicidade da Vacina , SARS-CoV-2/imunologia , Vacinas Sintéticas/imunologia , Animais , Anticorpos Neutralizantes/sangue , Vacinas contra COVID-19/administração & dosagem , Imunidade Celular , Esquemas de Imunização , Macaca mulatta , Masculino , Glicoproteína da Espícula de Coronavírus/imunologia , Linfócitos T/imunologia , Vacinas Sintéticas/administração & dosagem
18.
Nat Immunol ; 22(10): 1306-1315, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34417590

RESUMO

B.1.351 is the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variant most resistant to antibody neutralization. We demonstrate how the dose and number of immunizations influence protection. Nonhuman primates received two doses of 30 or 100 µg of Moderna's mRNA-1273 vaccine, a single immunization of 30 µg, or no vaccine. Two doses of 100 µg of mRNA-1273 induced 50% inhibitory reciprocal serum dilution neutralizing antibody titers against live SARS-CoV-2 p.Asp614Gly and B.1.351 of 3,300 and 240, respectively. Higher neutralizing responses against B.1.617.2 were also observed after two doses compared to a single dose. After challenge with B.1.351, there was ~4- to 5-log10 reduction of viral subgenomic RNA and low to undetectable replication in bronchoalveolar lavages in the two-dose vaccine groups, with a 1-log10 reduction in nasal swabs in the 100-µg group. These data establish that a two-dose regimen of mRNA-1273 will be critical for providing upper and lower airway protection against major variants of concern.


Assuntos
Vacinas contra COVID-19/imunologia , COVID-19/imunologia , Primatas/imunologia , SARS-CoV-2/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , COVID-19/virologia , Linhagem Celular , Chlorocebus aethiops , Feminino , Humanos , Macaca mulatta , Masculino , Mesocricetus , Primatas/virologia , RNA Viral/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinação/métodos , Células Vero , Carga Viral/métodos
19.
Nat Commun ; 12(1): 4817, 2021 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-34376662

RESUMO

Engineered ectodomain trimer immunogens based on BG505 envelope glycoprotein are widely utilized as components of HIV vaccine development platforms. In this study, we used rhesus macaques to evaluate the immunogenicity of several stabilized BG505 SOSIP constructs both as free trimers and presented on a nanoparticle. We applied a cryoEM-based method for high-resolution mapping of polyclonal antibody responses elicited in immunized animals (cryoEMPEM). Mutational analysis coupled with neutralization assays were used to probe the neutralization potential at each epitope. We demonstrate that cryoEMPEM data can be used for rapid, high-resolution analysis of polyclonal antibody responses without the need for monoclonal antibody isolation. This approach allowed to resolve structurally distinct classes of antibodies that bind overlapping sites. In addition to comprehensive mapping of commonly targeted neutralizing and non-neutralizing epitopes in BG505 SOSIP immunogens, our analysis revealed that epitopes comprising engineered stabilizing mutations and of partially occupied glycosylation sites can be immunogenic.


Assuntos
Vacinas contra a AIDS/imunologia , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Formação de Anticorpos/imunologia , Anticorpos Anti-HIV/imunologia , Produtos do Gene env do Vírus da Imunodeficiência Humana/imunologia , Animais , Anticorpos Monoclonais/química , Anticorpos Monoclonais/ultraestrutura , Anticorpos Neutralizantes/química , Anticorpos Neutralizantes/ultraestrutura , Microscopia Crioeletrônica/métodos , Epitopos/química , Epitopos/imunologia , Epitopos/metabolismo , Glicosilação , Anticorpos Anti-HIV/química , Anticorpos Anti-HIV/ultraestrutura , Infecções por HIV/imunologia , Infecções por HIV/prevenção & controle , Infecções por HIV/virologia , HIV-1/genética , HIV-1/imunologia , HIV-1/metabolismo , Humanos , Macaca mulatta , Modelos Moleculares , Conformação Proteica , Produtos do Gene env do Vírus da Imunodeficiência Humana/ultraestrutura
20.
Nat Commun ; 12(1): 4830, 2021 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-34376663

RESUMO

Choice-relevant brain regions in prefrontal cortex may progressively transform information about options into choices. Here, we examine responses of neurons in four regions of the medial prefrontal cortex as macaques performed two-option risky choices. All four regions encode economic variables in similar proportions and show similar putative signatures of key choice-related computations. We provide evidence to support a gradient of function that proceeds from areas 14 to 25 to 32 to 24. Specifically, we show that decodability of twelve distinct task variables increases along that path, consistent with the idea that regions that are higher in the anatomical hierarchy make choice-relevant variables more separable. We also show progressively longer intrinsic timescales in the same series. Together these results highlight the importance of the medial wall in choice, endorse a specific gradient-based organization, and argue against a modular functional neuroanatomy of choice.


Assuntos
Comportamento de Escolha/fisiologia , Macaca mulatta/fisiologia , Neurônios/fisiologia , Córtex Pré-Frontal/fisiologia , Potenciais de Ação/fisiologia , Algoritmos , Animais , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Mapeamento Encefálico , Imageamento por Ressonância Magnética/métodos , Modelos Neurológicos , Córtex Pré-Frontal/citologia
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