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1.
Front Immunol ; 11: 2059, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33013871

RESUMO

The novel, highly contagious coronavirus SARS-CoV-2 spreads rapidly throughout the world, leading to a deadly pandemic of a predominantly respiratory illness called COVID-19. Safe and effective anti-SARS-CoV-2 vaccines are urgently needed. However, emerging immunological observations show hallmarks of significant immunopathological characteristics and dysfunctional immune responses in patients with COVID-19. Combined with existing knowledge about immune responses to other closely related and highly pathogenic coronaviruses, this could forebode significant challenges for vaccine development, including the risk of vaccine failure. Animal data from earlier coronavirus vaccine efforts indicate that elderly people, most at risk from severe COVID-19 disease, could be especially at risk from immunopathologic responses to novel coronavirus vaccines. Bacterial "new old friends" such as Bacille Calmette-Guérin (BCG) or Mycobacterium obuense have the ability to elevate basal systemic levels of type 1 cytokines and immune cells, correlating with increased protection against diverse and unrelated infectious agents, called "trained immunity." Here we describe dysfunctional immune responses induced by coronaviruses, representing potentially difficult to overcome obstacles to safe, effective vaccine development for COVID-19, and outline how trained immunity could help protect high risk populations through immunomodulation with BCG and other "new old friends."


Assuntos
Vacina BCG/imunologia , Betacoronavirus/imunologia , Infecções por Coronavirus/imunologia , Imunidade Celular , Imunidade Inata , Memória Imunológica/imunologia , Pneumonia Viral/imunologia , Vacinação , Idoso , Animais , Vacinas Anticâncer/imunologia , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/virologia , Humanos , Micobactérias não Tuberculosas/imunologia , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Pneumonia Viral/virologia , Risco , Vacinas Virais/efeitos adversos
2.
Mediators Inflamm ; 2020: 6914878, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33061829

RESUMO

Background: COVID-19 caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has threatened every civilian as a global pandemic. The immune system poses the critical interactive chain between the human body and the virus. Here, we make efforts to examine whether comorbidity with type 2 diabetes (T2D) affects the immunological response in COVID-19 patients. Methods: We conducted a retrospective pilot study investigating immunological characteristics of confirmed cases of COVID-19 with or without comorbid T2D. Two subcohorts of sex- and age-matched participants were eligible for data analysis, of which 33 participants were with T2D and the remaining 37 were nondiabetic (NDM). Cellular immunity was assessed by flow cytometric determination of surface markers including CD3, CD4, CD8, CD19, CD16, and CD56 in peripheral blood. Levels of C reactive protein, immunoglobulin (IgG, IgM, IgA, and IgE), and complements (C3, C4) were detected by rate nephelometry immunoassay. And Th1/Th2 cytokines (IL-2, IL-4, IL-6, IL-10, TNF-α, and IFN-γ) were detected by Cytometric Bead Array. Results: Neutrophil counts were found to be significantly higher in the T2D group than in the NDM group and had a significant relevance with clinical severity. Lymphocyte frequencies showed no significant differences in the two groups. However, the proportions and absolute counts of T, Tc, Th, and NK cells decreased in both groups to different degrees. An abnormal increase in neutrophil count and a decrease in lymphocyte subpopulations may represent risk factors of COVID-19 severity. The level of IgG, IgM, IgA, C3, and C4 showed no significant difference between the two groups, while the IgE levels were higher in the T2D group than in the NDM group (p < 0.05). Th1 cytokines including IFN-γ, TNF-α, and IL-6, as well as CRP, appeared significantly higher in the T2D group. Conclusions: The COVID-19 patients comorbid with T2D demonstrated distinguishable immunological parameters, which represented clinical relevancies with the predisposed disease severity in T2D.


Assuntos
Betacoronavirus , Infecções por Coronavirus/imunologia , Diabetes Mellitus Tipo 2/imunologia , Pneumonia Viral/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , China/epidemiologia , Estudos de Coortes , Comorbidade , Proteínas do Sistema Complemento/metabolismo , Infecções por Coronavirus/complicações , Infecções por Coronavirus/epidemiologia , Citocinas/sangue , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Humanos , Imunidade Celular , Imunoglobulinas/sangue , Mediadores da Inflamação/sangue , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Pandemias , Projetos Piloto , Pneumonia Viral/complicações , Pneumonia Viral/epidemiologia , Estudos Retrospectivos , Células Th1/imunologia , Células Th2/imunologia
4.
Anticancer Res ; 40(10): 5329-5341, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32988851

RESUMO

Investigation of the efficacy and mechanisms of human immuno-oncology agents has been hampered due to species-specific differences when utilizing preclinical mouse models. Peripheral blood mononuclear cell (PBMC) humanized mice provide a platform for investigating the modulation of the human immune-mediated antitumor response while circumventing the limitations of syngeneic model systems. Use of humanized mice has been stymied by model-specific limitations, some of which include the development of graft versus host disease, technical difficulty and cost associated with each humanized animal, and insufficient engraftment of some human immune subsets. Recent advances have addressed many of these limitations from which have emerged humanized models that are more clinically relevant. This review characterizes the expanded usage, advantages and limitations of humanized mice and provides insights into the development of the next generation of murine humanized models to further inform clinical applications of cancer immunotherapeutic agents.


Assuntos
Imunidade Celular/efeitos dos fármacos , Imunoterapia , Leucócitos Mononucleares/imunologia , Neoplasias/tratamento farmacológico , Animais , Anticorpos Monoclonais Humanizados/imunologia , Anticorpos Monoclonais Humanizados/farmacologia , Antineoplásicos/imunologia , Antineoplásicos/farmacologia , Modelos Animais de Doenças , Humanos , Leucócitos Mononucleares/efeitos dos fármacos , Camundongos , Neoplasias/imunologia , Neoplasias/patologia
5.
Anticancer Res ; 40(10): 5355-5359, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32988854

RESUMO

BACKGROUND/AIM: Recent studies indicate that chimeric antigen receptor (CAR)-T-cells seem to be superior to CAR modified NK-92 cells. One, at least partial, explanation to this discrepancy has been addressed herein, by having NK-92 cells as target cells in cytotoxicity reactions using peripheral blood mononuclear cells. MATERIALS AND METHODS: A time-resolved fluorometric assay (TDA-labeled NK-92 or K562 as target cells) was used for measuring the cytotoxic activity of blood mononuclear cells (PBMC). RESULTS: The cytotoxic capacity of the NK-92 cells was initially demonstrated by their ability to efficiently kill K562 cells. Interestingly, having PBMC as effector cells rendered the very same NK-92 cells sensitive to NK-cell mediated cytolysis. A 1:100 target:effector ratio gave 34.1% lysis compared to 72.2% lysis for K562 cells. Incubating PBMC for longer times (24 up to 48 h) potentiated their NK-activity against NK-92 cells even more, reaching a level close to that obtained with K562 cells. CONCLUSION: This study pinpoints a severe problem that has to be considered in future immune-based cancer therapies with NK-92 as well as CAR-transduced NK-92 cells.


Assuntos
Imunoterapia Adotiva , Células Matadoras Naturais/efeitos dos fármacos , Leucócitos Mononucleares/efeitos dos fármacos , Neoplasias/terapia , Citotoxicidade Imunológica/efeitos dos fármacos , Humanos , Imunidade Celular/efeitos dos fármacos , Imunidade Celular/imunologia , Interleucina-2/genética , Interleucina-2/imunologia , Células K562 , Neoplasias/imunologia , Receptores de Antígenos Quiméricos/genética , Receptores de Antígenos Quiméricos/imunologia
6.
PLoS Pathog ; 16(9): e1008827, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32886721

RESUMO

Global burden of cervical cancer, the most common cause of mortality caused by human papillomavirus (HPV), is expected to increase during the next decade, mainly because current alternatives for HPV vaccination and cervical cancer screening programs are costly to be established in low-and-middle income countries. Recently, we described the development of the broadly protective, thermostable vaccine antigen Trx-8mer-OVX313 based on the insertion of eight different minor capsid protein L2 neutralization epitopes into a thioredoxin scaffold from the hyperthermophilic archaeon Pyrococcus furiosus and conversion of the resulting antigen into a nanoparticle format (median radius ~9 nm) upon fusion with the heptamerizing OVX313 module. Here we evaluated whether the engineered thioredoxin scaffold, in addition to humoral immune responses, can induce CD8+ T-cell responses upon incorporation of MHC-I-restricted epitopes. By systematically examining the contribution of individual antigen modules, we demonstrated that B-cell and T-cell epitopes can be combined into a single antigen construct without compromising either immunogenicity. While CD8+ T-cell epitopes had no influence on B-cell responses, the L2 polytope (8mer) and OVX313-mediated heptamerization of the final antigen significantly increased CD8+ T-cell responses. In a proof-of-concept experiment, we found that vaccinated mice remained tumor-free even after two consecutive tumor challenges, while unvaccinated mice developed tumors. A cost-effective, broadly protective vaccine with both prophylactic and therapeutic properties represents a promising option to overcome the challenges associated with prevention and treatment of HPV-caused diseases.


Assuntos
Antígenos de Neoplasias , Antígenos Virais , Proteínas Arqueais , Linfócitos T CD8-Positivos/imunologia , Vacinas Anticâncer , Imunidade Celular/efeitos dos fármacos , Nanopartículas , Papillomaviridae , Vacinas contra Papillomavirus , Pyrococcus furiosus/química , Tiorredoxinas , Neoplasias do Colo do Útero/imunologia , Animais , Antígenos de Neoplasias/química , Antígenos de Neoplasias/farmacologia , Antígenos Virais/química , Antígenos Virais/farmacologia , Proteínas Arqueais/química , Proteínas Arqueais/farmacologia , Linfócitos T CD8-Positivos/patologia , Vacinas Anticâncer/química , Vacinas Anticâncer/farmacologia , Epitopos de Linfócito B/química , Epitopos de Linfócito B/farmacologia , Epitopos de Linfócito T/química , Epitopos de Linfócito T/farmacologia , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Nanopartículas/química , Nanopartículas/uso terapêutico , Papillomaviridae/química , Papillomaviridae/imunologia , Vacinas contra Papillomavirus/química , Vacinas contra Papillomavirus/farmacologia , Tiorredoxinas/química , Tiorredoxinas/farmacologia , Neoplasias do Colo do Útero/virologia
7.
Lancet Oncol ; 21(9): e419-e430, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32888471

RESUMO

Notable advances have been achieved in the treatment of cancer since the advent of immunotherapy, and immune checkpoint inhibitors have shown clinical benefit across a wide variety of tumour types. Nevertheless, most patients still progress on these treatments, highlighting the importance of unravelling the underlying mechanisms of primary resistance to immunotherapy. A well described biomarker of non-responsiveness to immune checkpoint inhibitors is the absence or low presence of lymphocytes in the tumour microenvironment, so-called cold tumours. There are five mechanisms of action that have the potential to turn cold tumours into so-called hot and inflamed tumours, hence increasing the tumour's responsiveness to immunotherapy-increasing local inflammation, neutralising immunosuppression at the tumour site, modifying the tumour vasculature, targeting the tumour cells themselves, or increasing the frequency of tumour-specific T cells. In this Review, we discuss preclinical data that serves as the basis for ongoing immunotherapy clinical trials for the treatment of non-immunoreactive tumours, as well as reviewing clinical and translational data where available. We explain how improving our understanding of the underlying mechanisms of primary resistance to immunotherapy will help elucidate an increasingly granular view of the tumour microenvironment cellular composition, functional status, and cellular localisation, with the goal of further therapy refinement.


Assuntos
Resistencia a Medicamentos Antineoplásicos/imunologia , Imunoterapia/efeitos adversos , Inflamação/terapia , Neoplasias/terapia , Microambiente Tumoral/efeitos dos fármacos , Antineoplásicos Imunológicos/imunologia , Antineoplásicos Imunológicos/uso terapêutico , Quinase 1 do Ponto de Checagem/antagonistas & inibidores , Quinase 1 do Ponto de Checagem/imunologia , Ensaios Clínicos como Assunto , Humanos , Imunidade Celular/imunologia , Inflamação/imunologia , Inflamação/patologia , Linfócitos/efeitos dos fármacos , Linfócitos/imunologia , Neoplasias/imunologia , Neoplasias/patologia , Microambiente Tumoral/imunologia
9.
mBio ; 11(5)2020 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-32948688

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection induces a T cell response that most likely contributes to virus control in COVID-19 patients but may also induce immunopathology. Until now, the cytotoxic T cell response has not been very well characterized in COVID-19 patients. Here, we analyzed the differentiation and cytotoxic profile of T cells in 30 cases of mild COVID-19 during acute infection. SARS-CoV-2 infection induced a cytotoxic response of CD8+ T cells, but not CD4+ T cells, characterized by the simultaneous production of granzyme A and B as well as perforin within different effector CD8+ T cell subsets. PD-1-expressing CD8+ T cells also produced cytotoxic molecules during acute infection, indicating that they were not functionally exhausted. However, in COVID-19 patients over the age of 80 years, the cytotoxic T cell potential was diminished, especially in effector memory and terminally differentiated effector CD8+ cells, showing that elderly patients have impaired cellular immunity against SARS-CoV-2. Our data provide valuable information about T cell responses in COVID-19 patients that may also have important implications for vaccine development.IMPORTANCE Cytotoxic T cells are responsible for the elimination of infected cells and are key players in the control of viruses. CD8+ T cells with an effector phenotype express cytotoxic molecules and are able to perform target cell killing. COVID-19 patients with a mild disease course were analyzed for the differentiation status and cytotoxic profile of CD8+ T cells. SARS-CoV-2 infection induced a vigorous cytotoxic CD8+ T cell response. However, this cytotoxic profile of T cells was not detected in COVID-19 patients over the age of 80 years. Thus, the absence of a cytotoxic response in elderly patients might be a possible reason for the more frequent severity of COVID-19 in this age group than in younger patients.


Assuntos
Linfócitos T CD8-Positivos/patologia , Infecções por Coronavirus/imunologia , Pneumonia Viral/imunologia , Linfócitos T Citotóxicos/patologia , Idoso de 80 Anos ou mais , Antígenos CD/metabolismo , Betacoronavirus/patogenicidade , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/imunologia , Citotoxinas/metabolismo , Feminino , Humanos , Imunidade Celular , Masculino , Pessoa de Meia-Idade , Pandemias , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/patologia , Linfócitos T Citotóxicos/imunologia
10.
Nat Commun ; 11(1): 4454, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32901001

RESUMO

Chronic viral infections are often associated with impaired CD8+ T cell function, referred to as exhaustion. Although the molecular and cellular circuits involved in CD8+ T cell exhaustion are well defined, with sustained presence of antigen being one important parameter, how much T cell receptor (TCR) signaling is actually ongoing in vivo during established chronic infection is unclear. Here, we characterize the in vivo TCR signaling of virus-specific exhausted CD8+ T cells in a mouse model, leveraging TCR signaling reporter mice in combination with transcriptomics. In vivo signaling in exhausted cells is low, in contrast to their in vitro signaling potential, and despite antigen being abundantly present. Both checkpoint blockade and adoptive transfer of naïve target cells increase TCR signaling, demonstrating that engagement of co-inhibitory receptors curtails CD8+ T cell signaling and function in vivo.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Coriomeningite Linfocítica/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Transferência Adotiva , Animais , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/imunologia , Linfócitos T CD8-Positivos/virologia , Doença Crônica , Citotoxicidade Imunológica , Modelos Animais de Doenças , Regulação para Baixo , Tolerância Imunológica , Imunidade Celular , Técnicas In Vitro , Ativação Linfocitária , Coriomeningite Linfocítica/genética , Vírus da Coriomeningite Linfocítica/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares/genética , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares/imunologia , Receptor de Morte Celular Programada 1/imunologia , RNA-Seq , Transdução de Sinais/imunologia
11.
Proc Natl Acad Sci U S A ; 117(39): 24464-24474, 2020 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-32929007

RESUMO

Microglia are considered both pathogenic and protective during recovery from demyelination, but their precise role remains ill defined. Here, using an inhibitor of colony stimulating factor 1 receptor (CSF1R), PLX5622, and mice infected with a neurotropic coronavirus (mouse hepatitis virus [MHV], strain JHMV), we show that depletion of microglia during the time of JHMV clearance resulted in impaired myelin repair and prolonged clinical disease without affecting the kinetics of virus clearance. Microglia were required only during the early stages of remyelination. Notably, large deposits of extracellular vesiculated myelin and cellular debris were detected in the spinal cords of PLX5622-treated and not control mice, which correlated with decreased numbers of oligodendrocytes in demyelinating lesions in drug-treated mice. Furthermore, gene expression analyses demonstrated differential expression of genes involved in myelin debris clearance, lipid and cholesterol recycling, and promotion of oligodendrocyte function. The results also demonstrate that microglial functions affected by depletion could not be compensated by infiltrating macrophages. Together, these results demonstrate that microglia play key roles in debris clearance and in the initiation of remyelination following infection with a neurotropic coronavirus but are not necessary during later stages of remyelination.


Assuntos
Infecções por Coronavirus/patologia , Doenças Desmielinizantes/patologia , Microglia/patologia , Remielinização , Animais , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Doenças Desmielinizantes/imunologia , Doenças Desmielinizantes/virologia , Modelos Animais de Doenças , Feminino , Regulação da Expressão Gênica , Imunidade Celular/efeitos dos fármacos , Inflamação , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microglia/efeitos dos fármacos , Microglia/metabolismo , Vírus da Hepatite Murina/efeitos dos fármacos , Vírus da Hepatite Murina/fisiologia , Bainha de Mielina/metabolismo , Bainha de Mielina/patologia , Oligodendroglia/patologia , Compostos Orgânicos/administração & dosagem , Compostos Orgânicos/efeitos adversos , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos/antagonistas & inibidores , Remielinização/genética , Medula Espinal/imunologia , Medula Espinal/patologia
13.
APMIS ; 128(11): 593-602, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32870528

RESUMO

Induction of broad Th1 cellular immune responses and cytokines is crucial characteristics for vaccines against intracellular infections such as hepatitis C virus (HCV). Plants (especially oilseed tissues) and plant-immunomodulators (like oil bodies) offer cost-effective and scalable possibilities for the production of immunologically relevant and safe vaccine antigens and adjuvants, respectively. Herein, we provide data of the murine immunization by transgenic canola oilseed-derived HCV core protein (HCVcp) soluble extract (TSE) and Escherichia coli- derived rHCVcp in combination with Canola oil bodies (oil) compared to that of the Freund's (FA) adjuvant. Mice immunized by TSE+ oil developed both strong humeral (IgG) and Th1-biased cellular responses, manifested by high levels of IFN-γ and lower IgG1/IgG2a ratio and IL-4 secretion. Results of the intracellular cytokine staining indicated that TSE+ oil immunization in mice triggered both CD4+ and CD8+ T cells to release IFN-γ, while CD4+ cells were mostly triggered when FA was used. Analyses by qRT-PCR indicated that a combination of rHCVcp/TSE with oil body induced high levels of IL-10 cytokines compared to that of the FA adjuvant. These characteristics are important properties for the design of an HCV vaccine candidate and indicate the potential of Canola-derived antigen and oil bodies in addressing these concerns.


Assuntos
Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/prevenção & controle , Proteínas Recombinantes/administração & dosagem , Células Th1/efeitos dos fármacos , Proteínas do Core Viral/administração & dosagem , Vacinas contra Hepatite Viral/administração & dosagem , Adjuvantes Imunológicos/administração & dosagem , Adjuvantes Imunológicos/química , Animais , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/virologia , Escherichia coli/genética , Escherichia coli/metabolismo , Feminino , Hepacivirus/imunologia , Hepacivirus/patogenicidade , Hepatite C Crônica/imunologia , Hepatite C Crônica/patologia , Hepatite C Crônica/virologia , Imunidade Celular/efeitos dos fármacos , Imunoglobulina G/biossíntese , Interferon gama/biossíntese , Interferon gama/imunologia , Interleucina-10/biossíntese , Interleucina-10/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Óleo de Brassica napus/administração & dosagem , Óleo de Brassica napus/química , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/imunologia , Células Th1/imunologia , Células Th1/virologia , Proteínas do Core Viral/biossíntese , Proteínas do Core Viral/imunologia , Vacinas contra Hepatite Viral/biossíntese
14.
Lancet ; 396(10255): 887-897, 2020 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-32896291

RESUMO

BACKGROUND: We developed a heterologous COVID-19 vaccine consisting of two components, a recombinant adenovirus type 26 (rAd26) vector and a recombinant adenovirus type 5 (rAd5) vector, both carrying the gene for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike glycoprotein (rAd26-S and rAd5-S). We aimed to assess the safety and immunogenicity of two formulations (frozen and lyophilised) of this vaccine. METHODS: We did two open, non-randomised phase 1/2 studies at two hospitals in Russia. We enrolled healthy adult volunteers (men and women) aged 18-60 years to both studies. In phase 1 of each study, we administered intramuscularly on day 0 either one dose of rAd26-S or one dose of rAd5-S and assessed the safety of the two components for 28 days. In phase 2 of the study, which began no earlier than 5 days after phase 1 vaccination, we administered intramuscularly a prime-boost vaccination, with rAd26-S given on day 0 and rAd5-S on day 21. Primary outcome measures were antigen-specific humoral immunity (SARS-CoV-2-specific antibodies measured by ELISA on days 0, 14, 21, 28, and 42) and safety (number of participants with adverse events monitored throughout the study). Secondary outcome measures were antigen-specific cellular immunity (T-cell responses and interferon-γ concentration) and change in neutralising antibodies (detected with a SARS-CoV-2 neutralisation assay). These trials are registered with ClinicalTrials.gov, NCT04436471 and NCT04437875. FINDINGS: Between June 18 and Aug 3, 2020, we enrolled 76 participants to the two studies (38 in each study). In each study, nine volunteers received rAd26-S in phase 1, nine received rAd5-S in phase 1, and 20 received rAd26-S and rAd5-S in phase 2. Both vaccine formulations were safe and well tolerated. The most common adverse events were pain at injection site (44 [58%]), hyperthermia (38 [50%]), headache (32 [42%]), asthenia (21 [28%]), and muscle and joint pain (18 [24%]). Most adverse events were mild and no serious adverse events were detected. All participants produced antibodies to SARS-CoV-2 glycoprotein. At day 42, receptor binding domain-specific IgG titres were 14 703 with the frozen formulation and 11 143 with the lyophilised formulation, and neutralising antibodies were 49·25 with the frozen formulation and 45·95 with the lyophilised formulation, with a seroconversion rate of 100%. Cell-mediated responses were detected in all participants at day 28, with median cell proliferation of 2·5% CD4+ and 1·3% CD8+ with the frozen formulation, and a median cell proliferation of 1·3% CD4+ and 1·1% CD8+ with the lyophilised formulation. INTERPRETATION: The heterologous rAd26 and rAd5 vector-based COVID-19 vaccine has a good safety profile and induced strong humoral and cellular immune responses in participants. Further investigation is needed of the effectiveness of this vaccine for prevention of COVID-19. FUNDING: Ministry of Health of the Russian Federation.


Assuntos
Infecções por Coronavirus/prevenção & controle , Imunização Secundária , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Vacinas Virais/imunologia , Adenoviridae , Adulto , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Betacoronavirus , Infecções por Coronavirus/imunologia , Feminino , Humanos , Imunidade Celular , Imunidade Humoral , Imunoglobulina G/sangue , Injeções Intramusculares , Masculino , Federação Russa , Vacinas Virais/efeitos adversos , Adulto Jovem
15.
Virulence ; 11(1): 1250-1256, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32921249

RESUMO

The cause of some patients with negative RT-PCR results experienced turn-positive after treatment remains unclear. In addition, understanding the correlation between changes in clinical data in the course of COVID-19 and treatment outcomes is of great importance in determining the prognosis of COVID-19. To perform cause analysis of RT-PCR turn-positive and the effective screening factors related to treatment outcome in COVID-19. Clinical data, including clinical manifestations, laboratory tests, radiography results, treatment methods and outcomes, were retrospectively collected and analyzed from January to March 2020 in Renmin Hospitals of Wuhan University. 116 COVID-19 patients (40 in recurrent group, 29 in recovered group and 47 in unrecovered group) were recruited. In the recurrent group, white blood cell, Neutrophils, prothrombin time, activated partial thromboplastin time, CD3, CD4, CD8, ratio of CD4/CD8, IgG and C4 complement were of significant difference among the baseline, negative and turn-positive time points. CD19 and CT scan results were found notable difference between recurrent group and recovered group. Odds from CD3, CD4, CD8, CD19, IgM, C3 complement, C4 complement and CT scan results validated associations with clinical outcomes of COVID-19. The so-called recurrence in some COVID-19 patients may be due to the false-negative of nucleic acid test results from nasopharyngeal swabs. Levels of CD3, CD4, CD8, CD19, IgM, C3 complement, C4 complement and CT results were significantly correlated with the outcome of COVID-19. The cellular immunity test could be beneficial to further screen the reliability of RT-PCR test on the basis of CT images.


Assuntos
Betacoronavirus , Técnicas de Laboratório Clínico , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/terapia , Pneumonia Viral/diagnóstico , Pneumonia Viral/terapia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Adulto , Betacoronavirus/imunologia , Betacoronavirus/patogenicidade , China/epidemiologia , Estudos de Coortes , Infecções por Coronavirus/epidemiologia , Reações Falso-Negativas , Feminino , Humanos , Imunidade Celular , Pulmão/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/epidemiologia , Prognóstico , Recidiva , Estudos Retrospectivos , Fatores de Risco , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Virulência
17.
Sheng Wu Gong Cheng Xue Bao ; 36(7): 1378-1385, 2020 Jul 25.
Artigo em Chinês | MEDLINE | ID: mdl-32748595

RESUMO

Listeria monocytogenes (Lm) is zoonotic pathogen that can cause listeriosis, and vaccine is one of the effective methods to prevent this pathogen infection. In this study, we developed a novel vaccine that is a mixture of inactivated bacteria and Montanide™ ISA 61 VG, a mineral oil adjuvant, and evaluated the safety and immune response characteristics of this vaccine. The mice immunized with the ISA 61 VG adjuvant had high safety, and it could induce significantly higher titer of anti-listeriolysin O (LLO) antibody and higher value of IgG2a/IgG1 ratio compared with the group without the adjuvant. In particular, it could provide 100% immune protection against lethal doses of Lm challenge in mice. In summary, ISA 61VG adjuvant significantly enhanced the ability of inactivated listeria vaccine to induce humoral and cellular immune responses, thereby enhanced the protective immune response in the host, and it is a potential vaccine candidate for the prevention of Lm infection in humans and animals.


Assuntos
Adjuvantes Imunológicos , Proteínas Hemolisinas , Imunidade Celular , Listeria monocytogenes , Listeriose , Adjuvantes Imunológicos/farmacologia , Animais , Proteínas Hemolisinas/imunologia , Proteínas Hemolisinas/farmacologia , Imunidade Celular/efeitos dos fármacos , Listeria monocytogenes/imunologia , Listeriose/prevenção & controle , Camundongos , Camundongos Endogâmicos BALB C , Vacinas de Produtos Inativados/imunologia
18.
Sheng Wu Gong Cheng Xue Bao ; 36(7): 1440-1449, 2020 Jul 25.
Artigo em Chinês | MEDLINE | ID: mdl-32748602

RESUMO

Hepatitis B virus core protein can self-assemble into icosahedral symmetrical viral-like particles (VLPs) in vitro, and display exogenous sequences repeatedly and densely on the surface. VLPs also have strong immunogenicity and biological activity. When the nanoparticles enter the body, they quickly induce specific humoral and cellular immune responses to exogenous antigens. In this study, we designed an HBc-VLPs that can be coupled with antigens at specific sites, and developed a set of efficient methods to prepare HBc-VLPs. Through site-specific mutation technology, the 80th amino acid of peptide was changed from Ala to Cys, a specific cross-linking site was inserted into the main immunodominant region of HBc-VLPs, and the prokaryotic expression vector pET28a(+)-hbc was constructed. After expression and purification, high purity HBc(A80C) monomer protein was assembled into HBc-VLPs nanoparticles in Phosphate Buffer. The results of particle size analysis show that the average particle size of nanoparticles was 29.8 nm. Transmission electron microscopy (TEM) showed that HBc-VLPs formed spherical particles with a particle size of about 30 nm, and its morphology was similar to that of natural HBV particles. The influenza virus antigen M2e peptide as model antigen was connected to Cys residue of HBc-VLPs by Sulfo-SMCC, an amino sulfhydryl bifunctional cross-linking agent, and M2e-HBc-VLPs model vaccine was prepared. The integrity of HBc-VLPs structure and the correct cross-linking of M2e were verified by cell fluorescence tracing. Animal immune experiments showed that the vaccine can effectively stimulate the production of antigen-specific IgG antibody in mice, which verified the effectiveness of the vaccine carrier HBc-VLPs. This study lays a foundation for the research of HBc-VLPs as vaccine vector, and help to promote the development of HBc-VLPs vaccine and the application of HBc-VLPs in other fields.


Assuntos
Antígenos do Núcleo do Vírus da Hepatite B , Imunidade Celular , Vacinas de Partículas Semelhantes a Vírus , Animais , Antígenos do Núcleo do Vírus da Hepatite B/genética , Antígenos do Núcleo do Vírus da Hepatite B/imunologia , Imunidade Celular/imunologia , Imunoglobulina G/sangue , Camundongos , Camundongos Endogâmicos BALB C , Vacinas de Partículas Semelhantes a Vírus/genética , Vacinas de Partículas Semelhantes a Vírus/imunologia
19.
Signal Transduct Target Ther ; 5(1): 156, 2020 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-32796814

RESUMO

The global Coronavirus disease 2019 (COVID-19) pandemic caused by SARS-CoV-2 has affected more than eight million people. There is an urgent need to investigate how the adaptive immunity is established in COVID-19 patients. In this study, we profiled adaptive immune cells of PBMCs from recovered COVID-19 patients with varying disease severity using single-cell RNA and TCR/BCR V(D)J sequencing. The sequencing data revealed SARS-CoV-2-specific shuffling of adaptive immune repertories and COVID-19-induced remodeling of peripheral lymphocytes. Characterization of variations in the peripheral T and B cells from the COVID-19 patients revealed a positive correlation of humoral immune response and T-cell immune memory with disease severity. Sequencing and functional data revealed SARS-CoV-2-specific T-cell immune memory in the convalescent COVID-19 patients. Furthermore, we also identified novel antigens that are responsive in the convalescent patients. Altogether, our study reveals adaptive immune repertories underlying pathogenesis and recovery in severe versus mild COVID-19 patients, providing valuable information for potential vaccine and therapeutic development against SARS-CoV-2 infection.


Assuntos
Linfócitos B/imunologia , Betacoronavirus/patogenicidade , Infecções por Coronavirus/imunologia , Imunidade Celular , Imunidade Humoral , Pneumonia Viral/imunologia , Linfócitos T/imunologia , Antígenos Virais/genética , Antígenos Virais/imunologia , Linfócitos B/classificação , Linfócitos B/virologia , Betacoronavirus/imunologia , Estudos de Casos e Controles , China , Convalescença , Infecções por Coronavirus/genética , Infecções por Coronavirus/patologia , Infecções por Coronavirus/virologia , Progressão da Doença , Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Interações Hospedeiro-Patógeno/imunologia , Humanos , Memória Imunológica , Pandemias , Pneumonia Viral/genética , Pneumonia Viral/patologia , Pneumonia Viral/virologia , Receptores de Antígenos de Linfócitos B/classificação , Receptores de Antígenos de Linfócitos B/genética , Receptores de Antígenos de Linfócitos B/imunologia , Receptores de Antígenos de Linfócitos T/classificação , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/imunologia , Índice de Gravidade de Doença , Análise de Célula Única , Linfócitos T/classificação , Linfócitos T/virologia
20.
J Immunol Res ; 2020: 8624963, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32802896

RESUMO

Single-cell RNA sequencing allows highly detailed profiling of cellular immune responses from limited-volume samples, advancing prospects of a new era of systems immunology. The power of single-cell RNA sequencing offers various opportunities to decipher the immune response to infectious diseases and vaccines. Here, we describe the potential uses of single-cell RNA sequencing methods in prophylactic vaccine development, concentrating on infectious diseases including COVID-19. Using examples from several diseases, we review how single-cell RNA sequencing has been used to evaluate the immunological response to different vaccine platforms and regimens. By highlighting published and unpublished single-cell RNA sequencing studies relevant to vaccinology, we discuss some general considerations how the field could be enriched with the widespread adoption of this technology.


Assuntos
Betacoronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , RNA-Seq/métodos , Análise de Célula Única , Vacinologia/métodos , Vacinas Virais/administração & dosagem , Animais , Linhagem Celular , Ensaios Clínicos como Assunto , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Humanos , Imunidade Celular/genética , Imunidade Inata/genética , Imunogenicidade da Vacina , Pneumonia Viral/epidemiologia , Pneumonia Viral/imunologia , Pneumonia Viral/virologia , RNA Viral/isolamento & purificação , Vacinas Virais/imunologia
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