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1.
J Infect Dis ; 224(5): 754-763, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34467985

RESUMO

BACKGROUND: There is insufficient data on the longevity of immunity acquired after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. METHODS: We aimed to evaluate the duration of SARS-CoV-2-specific humoral and cellular immunity according to the clinical severity of coronavirus disease 2019 (COVID-19). The study population comprised asymptomatic (n = 14), symptomatic/nonpneumonic (n = 42), and pneumonic (n = 41) patients. RESULTS: The anti-SARS-CoV-2 immunoglobulin class G and neutralizing antibody (NAb) titers lasted until 6 months after diagnosis, with positivity rates of 66.7% and 86.9%, respectively. Older age, prolonged viral shedding, and accompanying pneumonia were more frequently found in patients with sustained humoral immunity. Severe acute respiratory syndrome coronavirus 2-specific T-cell response was strongly observed in pneumonic patients and prominent in individuals with sustained humoral immunity. CONCLUSIONS: In conclusion, most (>85%) patients carry NAb until 6 months after diagnosis of SARS-CoV-2 infection, providing insights for establishing vaccination strategies against COVID-19.


Assuntos
COVID-19/imunologia , SARS-CoV-2/imunologia , Adulto , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , COVID-19/diagnóstico , COVID-19/virologia , Feminino , Humanos , Imunidade Celular , Imunidade Humoral , Imunoglobulina G/imunologia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Linfócitos T/imunologia , Eliminação de Partículas Virais
2.
J Immunol ; 207(5): 1377-1387, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34380645

RESUMO

T cells are essential mediators of immune responses against infectious diseases and provide long-lived protection from reinfection. The differentiation of naive to effector T cells and the subsequent differentiation and persistence of memory T cell populations in response to infection is a highly regulated process. E protein transcription factors and their inhibitors, Id proteins, are important regulators of both CD4+ and CD8+ T cell responses; however, their regulation at the protein level has not been explored. Recently, the deubiquitinase USP1 was shown to stabilize Id2 and modulate cellular differentiation in osteosarcomas. In this study, we investigated a role for Usp1 in posttranslational control of Id2 and Id3 in murine T cells. We show that Usp1 was upregulated in T cells following activation in vitro or following infection in vivo, and the extent of Usp1 expression correlated with the degree of T cell expansion. Usp1 directly interacted with Id2 and Id3 following T cell activation. However, Usp1 deficiency did not impact Id protein abundance in effector T cells or alter effector T cell expansion or differentiation following a primary infection. Usp1 deficiency resulted in a gradual loss of memory CD8+ T cells over time and reduced Id2 protein levels and proliferation of effector CD8+ T cell following reinfection. Together, these results identify Usp1 as a player in modulating recall responses at the protein level and highlight differences in regulation of T cell responses between primary and subsequent infection encounters. Finally, our observations reveal differential regulation of Id2/3 proteins between immune versus nonimmune cell types.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Proteases Específicas de Ubiquitina/metabolismo , Animais , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Imunidade Celular , Imunização , Memória Imunológica , Proteína 2 Inibidora de Diferenciação/metabolismo , Proteínas Inibidoras de Diferenciação/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Processamento de Proteína Pós-Traducional , Proteases Específicas de Ubiquitina/genética
3.
J Immunol ; 207(5): 1456-1467, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34380650

RESUMO

Cancer immunotherapy has shown great promise as a new standard therapeutic strategy against cancer. However, the response rate and survival benefit remain unsatisfactory because most current approaches, such as the use of immune checkpoint inhibitors, depend on spontaneous antitumor immune responses. One possibility for improving the efficacy of immunotherapy is to promote antitumor immunity using adjuvants or specific cytokines actively. IL-33 has been a candidate for such cytokine therapies, but it remains unclear how and in which situations IL-33 exerts antitumor immune effects. In this study, we demonstrate the potent antitumor effects of IL-33 using syngeneic mouse models, which included marked inhibition of tumor growth and upregulation of IFN-γ production by tumor-infiltrating CD8+ T cells. Of note, IL-33 induced dendritic cells to express semaphorin 4A (Sema4A), and the absence of Sema4A abolished the antitumor activity of IL-33, indicating that Sema4A is intrinsically required for the antitumor effects of IL-33 in mice. Collectively, these results not only present IL-33 and Sema4A as potential therapeutic targets but also shed light on the potential use of Sema4A as a biomarker for dendritic cell activation status, which has great value in various fields of cancer research, including vaccine development.


Assuntos
Carcinoma Pulmonar de Lewis/imunologia , Células Dendríticas/imunologia , Interleucina-33/metabolismo , Semaforinas/metabolismo , Animais , Biomarcadores/metabolismo , Diferenciação Celular , Modelos Animais de Doenças , Regulação Neoplásica da Expressão Gênica , Humanos , Imunidade Celular , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Transplante de Neoplasias , Semaforinas/genética
4.
Int J Mol Sci ; 22(16)2021 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-34445084

RESUMO

Atherosclerosis is the major cause of the development of cardiovascular disease, which, in turn, is one of the leading causes of mortality worldwide. From the point of view of pathogenesis, atherosclerosis is an extremely complex disease. A huge variety of processes, such as violation of mitophagy, oxidative stress, damage to the endothelium, and others, are involved in atherogenesis; however, the main components of atherogenesis are considered to be inflammation and alterations of lipid metabolism. In this review, we want to focus on inflammation, and more specifically on the cellular elements of adaptive immunity, T and B cells. It is known that various T cells are widely represented directly in atherosclerotic plaques, while B cells can be found, for example, in the adventitia layer. Of course, such widespread and well-studied cells have attracted attention as potential therapeutic targets for the treatment of atherosclerosis. Various approaches have been developed and tested for their efficacy.


Assuntos
Aterosclerose/imunologia , Linfócitos B/imunologia , Imunidade , Linfócitos T/imunologia , Imunidade Adaptativa , Animais , Aterosclerose/patologia , Linfócitos B/patologia , Humanos , Imunidade Celular , Inflamação/imunologia , Inflamação/patologia , Linfócitos T/patologia
6.
Sci Rep ; 11(1): 15927, 2021 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-34354210

RESUMO

Previous studies focusing on the age disparity in COVID-19 severity have suggested that younger individuals mount a more robust innate immune response in the nasal mucosa after infection with SARS-CoV-2. However, it is unclear if this reflects increased immune activation or increased immune residence in the nasal mucosa. We hypothesized that immune residency in the nasal mucosa of healthy individuals may differ across the age range. We applied single-cell RNA-sequencing and measured the cellular composition and transcriptional profile of the nasal mucosa in 35 SARS-CoV-2 negative children and adults, ranging in age from 4 months to 65 years. We analyzed in total of ~ 30,000 immune and epithelial cells and found that age and immune cell proportion in the nasal mucosa are inversely correlated, with little evidence for structural changes in the transcriptional state of a given cell type across the age range. Orthogonal validation by epigenome sequencing indicate that it is especially cells of the innate immune system that underlie the age-association. Additionally, we characterize the predominate immune cell type in the nasal mucosa: a resident T cell like population with potent antiviral properties. These results demonstrate fundamental changes in the immune cell makeup of the uninfected nasal mucosa over the lifespan. The resource we generate here is an asset for future studies focusing on respiratory infection and immunization strategies.


Assuntos
COVID-19/imunologia , Mucosa Nasal/imunologia , SARS-CoV-2/imunologia , Adolescente , Adulto , COVID-19/genética , Criança , Pré-Escolar , Feminino , Humanos , Imunidade Celular , Imunidade Inata , Lactente , Masculino , Pessoa de Meia-Idade , Mucosa Nasal/citologia , Mucosa Nasal/metabolismo , Índice de Gravidade de Doença , Linfócitos T/imunologia , Linfócitos T/metabolismo , Transcriptoma , Adulto Jovem
7.
Nat Commun ; 12(1): 4746, 2021 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-34362900

RESUMO

The function of MR1-restricted mucosal-associated invariant T (MAIT) cells in tumor immunity is unclear. Here we show that MAIT cell-deficient mice have enhanced NK cell-dependent control of metastatic B16F10 tumor growth relative to control mice. Analyses of this interplay in human tumor samples reveal that high expression of a MAIT cell gene signature negatively impacts the prognostic significance of NK cells. Paradoxically, pre-pulsing tumors with MAIT cell antigens, or activating MAIT cells in vivo, enhances anti-tumor immunity in B16F10 and E0771 mouse tumor models, including in the context of established metastasis. These effects are associated with enhanced NK cell responses and increased expression of both IFN-γ-dependent and inflammatory genes in NK cells. Importantly, activated human MAIT cells also promote the function of NK cells isolated from patient tumor samples. Our results thus describe an activation-dependent, MAIT cell-mediated regulation of NK cells, and suggest a potential therapeutic avenue for cancer treatment.


Assuntos
Imunidade Celular , Células Matadoras Naturais/imunologia , Células T Invariantes Associadas à Mucosa/imunologia , Neoplasias/imunologia , Animais , Antineoplásicos , Linhagem Celular Tumoral , Citocinas , Antígenos de Histocompatibilidade Classe I/genética , Humanos , Imunidade , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Antígenos de Histocompatibilidade Menor/genética , Metástase Neoplásica , Neoplasias/patologia
8.
Front Immunol ; 12: 720090, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34434199

RESUMO

Male sex and old age are risk factors for COVID-19 severity, but the underlying causes are unknown. A possible explanation for this might be the differences in immunological profiles in males and the elderly before the infection. With this in mind, we analyzed the abundance of circulating proteins and immune populations associated with severe COVID-19 in 2 healthy cohorts. Besides, given the seasonal profile of COVID-19, the seasonal response against SARS-CoV-2 could also be different in the elderly and males. Therefore, PBMCs of female, male, young, and old subjects in different seasons of the year were stimulated with heat-inactivated SARS-CoV-2 to investigate the season-dependent anti-SARS-CoV-2 immune response. We found that several T cell subsets, which are known to be depleted in severe COVID-19 patients, were intrinsically less abundant in men and older individuals. Plasma proteins increasing with disease severity, including HGF, IL-8, and MCP-1, were more abundant in the elderly and males. Upon in vitro SARS-CoV-2 stimulation, the elderly produced significantly more IL-1RA and had a dysregulated IFNγ response with lower production in the fall compared with young individuals. Our results suggest that the immune characteristics of severe COVID-19, described by a differential abundance of immune cells and circulating inflammatory proteins, are intrinsically present in healthy men and the elderly. This might explain the susceptibility of men and the elderly to SARS-CoV-2 infection.


Assuntos
COVID-19/imunologia , Adolescente , Adulto , Fatores Etários , Idoso , Envelhecimento/imunologia , Proteínas Sanguíneas/imunologia , COVID-19/fisiopatologia , Estudos de Coortes , Suscetibilidade a Doenças , Feminino , Humanos , Imunidade Celular , Fatores Imunológicos , Masculino , Pessoa de Meia-Idade , Gravidade do Paciente , Medição de Risco , Estações do Ano , Fatores Sexuais , Subpopulações de Linfócitos T/imunologia , Adulto Jovem
9.
Dtsch Med Wochenschr ; 146(16): 1085-1090, 2021 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-34416777

RESUMO

Since the end of 2019 a new coronavirus, SARS-CoV-2, first identified in Wuhan, China, is spreading around the world partially associated with a high death toll. Besides hygienic measurements to reduce the spread of the virus vaccines have been confected, partially based on the experiences with Ebola virus vaccine, based on recombinant human or chimpanzee adenovirus carrying the spike protein and its ACE2 receptor binding domain (RBD). Further vaccines are constructed by spike protein coding mRNA incorporated in lipid nano vesicles that after entry in human cells produce spike protein. Both vaccine types induce a strong immune response that lasts for months possibly for T-cell immunity a few years. Due to mutations in the coronavirus genome in several parts of the world variants selected, that were partially more pathogenic and partially easier transmissible - variants of concern (VOC). Until now vaccinees are protected against the VOC, even when protection might be reduced compared to the Wuhan wild virus.An open field is still how long the vaccine induced immunity will be sufficient to prevent infection and/or disease; and how long the time period will last until revaccination will be required for life saving protection, whether a third vaccination is needed, and whether revaccination with an adenovirus-based vaccine will be tolerated.


Assuntos
Vacinas contra COVID-19/imunologia , COVID-19/prevenção & controle , Sistema Imunitário/fisiologia , SARS-CoV-2/imunologia , Vacinação/normas , COVID-19/epidemiologia , COVID-19/fisiopatologia , Humanos , Sistema Imunitário/imunologia , Imunidade Celular , Imunidade Humoral , Fatores de Tempo
10.
Nat Commun ; 12(1): 4984, 2021 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-34404803

RESUMO

SARS-CoV-2 vaccination has been launched worldwide to build effective population-level immunity to curb the spread of this virus. The effectiveness and duration of protective immunity is a critical factor for public health. Here, we report the kinetics of the SARS-CoV-2 specific immune response in 204 individuals up to 1-year after recovery from COVID-19. RBD-IgG and full-length spike-IgG concentrations and serum neutralizing capacity decreases during the first 6-months, but is maintained stably up to 1-year after hospital discharge. Even individuals who had generated high IgG levels during early convalescent stages had IgG levels that had decreased to a similar level one year later. Notably, the RBD-IgG level positively correlates with serum neutralizing capacity, suggesting the representative role of RBD-IgG in predicting serum protection. Moreover, viral-specific cellular immune protection, including spike and nucleoprotein specific, persisted between 6 months and 12 months. Altogether, our study supports the persistence of viral-specific protective immunity over 1 year.


Assuntos
COVID-19/imunologia , SARS-CoV-2/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , COVID-19/sangue , Humanos , Imunidade Celular/imunologia , Imunidade Humoral/imunologia , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia
11.
J Immunol ; 207(5): 1322-1332, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34341171

RESUMO

MicroRNA-21 (miR-21) inhibits IL-12 expression and impairs the Th1 response necessary for control of Leishmania infection. Recent studies have shown that Leishmania infection induces miR-21 expression in dendritic cells and macrophages, and inhibition of miR-21 restores IL-12 expression. Because miR-21 is known to be expressed due to inflammatory stimuli in a wide range of hematopoietic cells, we investigated the role of miR-21 in regulating immune responses during visceral leishmaniasis (VL) caused by Leishmania donovani infection. We found that miR-21 expression was significantly elevated in dendritic cells, macrophages, inflammatory monocytes, polymorphonuclear neutrophils, and in the spleen and liver tissues after L. donovani infection, concomitant with an increased expression of disease exacerbating IL-6 and STAT3. Bone marrow dendritic cells from miR-21 knockout (miR-21KO) mice showed increased IL-12 production and decreased production of IL-10. On L. donovani infection, miR-21KO mice exhibited significantly greater numbers of IFN-γ- and TNF-α-producing CD4+ and CD8+ T cells in their organs that was associated with increased production of Th1-associated IFN-γ, TNF-α, and NO from the splenocytes. Finally, miR-21KO mice displayed significantly more developing and mature hepatic granulomas leading to reduction in organ parasitic loads compared with wild type counterparts. Similar results were noted in L. donovani-infected wild type mice after transient miR-21 depletion. These observations indicate that miR-21 plays a critical role in pathogenesis of VL by suppressing IL-12- and Th1-associated IFN-γ and also inducing disease-promoting induction of the IL-6 and STAT-3 signaling pathway. miR-21 could therefore be used as a potential target for developing host-directed treatment for VL.


Assuntos
Células Dendríticas/imunologia , Leishmania donovani/fisiologia , Leishmaniose Visceral/imunologia , MicroRNAs/genética , Monócitos/imunologia , Neutrófilos/imunologia , Células Th1/imunologia , Animais , Células Cultivadas , Modelos Animais de Doenças , Resistência à Doença , Imunidade Celular , Interleucina-6/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fator de Transcrição STAT3/metabolismo , Regulação para Cima
12.
J Immunol ; 207(5): 1419-1427, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34348974

RESUMO

Macrophage functional plasticity plays a central role in responding to proinflammatory stimuli. The molecular basis underlying the dynamic phenotypic activation of macrophages, however, remains incompletely understood. In this article, we report that SIRPα is a chief negative regulator of proinflammatory macrophage polarization. In response to TLR agonists, proinflammatory cytokines, or canonical M1 stimulation, Src family kinases (SFK) excluding Lyn phosphorylate SIRPα ITIMs, leading to the preferential recruitment and activation of SHP-1, but not SHP-2. Solely extracellular ligation of SIRPα by CD47 does not greatly induce phosphorylation of SIRPα ITIMs, but it enhances proinflammatory stimuli-induced SIRPα phosphorylation. Examination of downstream signaling elicited by IFN-γ and TLR3/4/9 agonists found that SIRPα-activated SHP-1 moderately represses STAT1, NF-κB, and MAPK signaling but markedly inhibits Akt2, resulting in dampened proinflammatory cytokine production and expression of Ag presentation machinery. Pharmacological inhibition of SHP-1 or deficiency of SIRPα conversely attenuates SIRPα-mediated inhibition and, as such, augments macrophage proinflammatory polarization that in turn exacerbates proinflammation in mouse models of type I diabetes and peritonitis. Our results reveal an SFK-SIRPα-SHP-1 mechanism that fine-tunes macrophage proinflammatory phenotypic activation via inhibition of PI3K-Akt2, which controls the transcription and translation of proinflammatory cytokines, Ag presentation machinery, and other cellular programs.


Assuntos
Inflamação/metabolismo , Macrófagos/imunologia , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo , Receptores Imunológicos/metabolismo , Animais , Apresentação do Antígeno , Diferenciação Celular , Células Cultivadas , Classe I de Fosfatidilinositol 3-Quinases/metabolismo , Citocinas/metabolismo , Imunidade Celular , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores Imunológicos/genética , Transdução de Sinais , Células Th1/imunologia
13.
Int J Mol Sci ; 22(15)2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34360889

RESUMO

Despite extensive research, there is still no vaccine against the hepatitis C virus (HCV). The aim of this study was to investigate whether MSCs can exhibit adjuvant properties during DNA vaccination against hepatitis C. We used the pcNS3-NS5B plasmid encoding five nonstructural HCV proteins and MSCs derived from mice bone marrow. Five groups of DBA mice were immunized with the plasmid and/or MSCs in a different order. Group 1 was injected with the plasmid twice at intervals of 3 weeks; Group 2 with the plasmid, and after 24 h with MSCs; Group 3 with MSCs followed by the plasmid the next day; Group 4 with only MSCs; and Group 5 with saline. When the MSCs were injected prior to DNA immunization, the cell immune response to HCV proteins assessed by the level of IFN-γ synthesis was markedly increased compared to DNA alone. In contrast, MSCs injected after DNA suppressed the immune response. Apparently, the high level of proinflammatory cytokines detected after DNA injection promotes the conversion of MSCs introduced later into the immunosuppressive MSC2. The low level of cytokines in mice before MSC administration promotes the high immunostimulatory activity of MSC1 in response to a DNA vaccine. Thus, when administered before DNA, MSCs are capable of exhibiting promising adjuvant properties.


Assuntos
Genes Virais/imunologia , Hepacivirus/genética , Hepacivirus/imunologia , Hepatite C/prevenção & controle , Imunidade Celular , Células-Tronco Mesenquimais/imunologia , Vacinação/métodos , Vacinas de DNA/administração & dosagem , Proteínas não Estruturais Virais/genética , Animais , Linhagem Celular Tumoral , Citocinas/metabolismo , Feminino , Hepatite C/imunologia , Hepatite C/virologia , Humanos , Camundongos , Camundongos Endogâmicos DBA , Plasmídeos/genética , Linfócitos T/imunologia , Transfecção , Resultado do Tratamento , Vacinas de DNA/imunologia
14.
EBioMedicine ; 70: 103524, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34391096

RESUMO

BACKGROUND: Patients with chronic renal insufficiency on maintenance haemodialysis face an increased risk of COVID-19 induced mortality and impaired vaccine responses. To date, only a few studies have addressed SARS-CoV-2 vaccine elicited immunity in this immunocompromised population. METHODS: We assessed immunogenicity of the mRNA vaccine BNT162b2 in at-risk dialysis patients and characterised systemic cellular and humoral immune responses in serum and saliva using interferon γ release assay and multiplex-based cytokine and immunoglobulin measurements. We further compared binding capacity and neutralization efficacy of vaccination-induced immunoglobulins against emerging SARS-CoV-2 variants Alpha, Beta, Epsilon and Cluster 5 by ACE2-RBD competition assay. FINDINGS: Patients on maintenance haemodialysis exhibit detectable but variable cellular and humoral immune responses against SARS-CoV-2 and variants of concern after a two-dose regimen of BNT162b2. Although vaccination-induced immunoglobulins were detectable in saliva and plasma, both anti-SARS-CoV-2 IgG and neutralization efficacy was reduced compared to a vaccinated non-dialysed control population. Similarly, T-cell mediated interferon γ release after stimulation with SARS-CoV-2 spike peptides was significantly diminished. INTERPRETATION: Quantifiable humoral and cellular immune responses after BNT162b2 vaccination in individuals on maintenance haemodialysis are encouraging, but urge for longitudinal follow-up to assess longevity of immunity. Diminished virus neutralization and interferon γ responses in the face of emerging variants of concern may favour this at-risk population for re-vaccination using modified vaccines at the earliest opportunity. FUNDING: Initiative and Networking Fund of the Helmholtz Association of German Research Centres, EU Horizon 2020 research and innovation program, State Ministry of Baden-Württemberg for Economic Affairs, Labour and Tourism.


Assuntos
Vacinas contra COVID-19/imunologia , COVID-19/imunologia , Imunidade Celular/imunologia , Imunidade Humoral/imunologia , Imunogenicidade da Vacina/imunologia , SARS-CoV-2/imunologia , Vacinas Sintéticas/imunologia , Idoso , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Feminino , Humanos , Imunoglobulina G/imunologia , Masculino , Pessoa de Meia-Idade , Diálise Renal/métodos , Glicoproteína da Espícula de Coronavírus/imunologia , Linfócitos T/imunologia , Vacinação/métodos
15.
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
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