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1.
Comput Math Methods Med ; 2020: 1352982, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32908574

RESUMO

The current emergence of coronavirus (SARS-CoV-2) puts the world in threat. The structural research on the receptor recognition by SARS-CoV-2 has identified the key interactions between SARS-CoV-2 spike protein and its host (epithelial cell) receptor, also known as angiotensin-converting enzyme 2 (ACE2). It controls both the cross-species and human-to-human transmissions of SARS-CoV-2. In view of this, we propose and analyze a mathematical model for investigating the effect of CTL responses over the viral mutation to control the viral infection when a postinfection immunostimulant drug (pidotimod) is administered at regular intervals. Dynamics of the system with and without impulses have been analyzed using the basic reproduction number. This study shows that the proper dosing interval and drug dose both are important to eradicate the viral infection.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Betacoronavirus , Infecções por Coronavirus/tratamento farmacológico , Modelos Biológicos , Pneumonia Viral/tratamento farmacológico , Ácido Pirrolidonocarboxílico/análogos & derivados , Tiazolidinas/administração & dosagem , Número Básico de Reprodução , Betacoronavirus/genética , Betacoronavirus/imunologia , Simulação por Computador , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/imunologia , Relação Dose-Resposta a Droga , Interações entre Hospedeiro e Microrganismos/efeitos dos fármacos , Interações entre Hospedeiro e Microrganismos/imunologia , Humanos , Conceitos Matemáticos , Mutação , Pandemias , Peptidil Dipeptidase A/fisiologia , Pneumonia Viral/epidemiologia , Pneumonia Viral/imunologia , Ácido Pirrolidonocarboxílico/administração & dosagem , Receptores Virais/fisiologia , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Linfócitos T Citotóxicos/imunologia
2.
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
4.
Nat Commun ; 11(1): 4835, 2020 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-32973173

RESUMO

Immune checkpoint blockade therapies have shown clinical promise in a variety of cancers, but how tumor-infiltrating T cells are activated remains unclear. In this study, we explore the functions of PD-L1 on dendritic cells (DCs), which highly express PD-L1. We observe that PD-L1 on DC plays a critical role in limiting T cell responses. Type 1 conventional DCs are essential for PD-L1 blockade and they upregulate PD-L1 upon antigen uptake. Upregulation of PD-L1 on DC is mediated by type II interferon. While DCs are the major antigen presenting cells for cross-presenting tumor antigens to T cells, subsequent PD-L1 upregulation protects them from killing by cytotoxic T lymphocytes, yet dampens the antitumor responses. Blocking PD-L1 in established tumors promotes re-activation of tumor-infiltrating T cells for tumor control. Our study identifies a critical and dynamic role of PD-L1 on DC, which needs to be harnessed for better invigoration of antitumor immune responses.


Assuntos
Antígeno B7-H1/metabolismo , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Ativação Linfocitária , Animais , Antígenos de Neoplasias/metabolismo , Antígeno B7-H1/genética , Linhagem Celular Tumoral , Modelos Animais de Doenças , Feminino , Células HEK293 , Humanos , Interferon gama/metabolismo , Linfócitos do Interstício Tumoral/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Linfócitos T Citotóxicos/imunologia , Microambiente Tumoral/imunologia , Regulação para Cima
5.
Nat Commun ; 11(1): 3946, 2020 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-32770055

RESUMO

Melanomas can switch to a dedifferentiated cell state upon exposure to cytotoxic T cells. However, it is unclear whether such tumor cells pre-exist in patients and whether they can be resensitized to immunotherapy. Here, we chronically expose (patient-derived) melanoma cell lines to differentiation antigen-specific cytotoxic T cells and observe strong enrichment of a pre-existing NGFRhi population. These fractions are refractory also to T cells recognizing non-differentiation antigens, as well as to BRAF + MEK inhibitors. NGFRhi cells induce the neurotrophic factor BDNF, which contributes to T cell resistance, as does NGFR. In melanoma patients, a tumor-intrinsic NGFR signature predicts anti-PD-1 therapy resistance, and NGFRhi tumor fractions are associated with immune exclusion. Lastly, pharmacologic NGFR inhibition restores tumor sensitivity to T cell attack in vitro and in melanoma xenografts. These findings demonstrate the existence of a stable and pre-existing NGFRhi multitherapy-refractory melanoma subpopulation, which ought to be eliminated to revert intrinsic resistance to immunotherapeutic intervention.


Assuntos
Antineoplásicos Imunológicos/farmacologia , Melanoma/tratamento farmacológico , Proteínas do Tecido Nervoso/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Receptores de Fator de Crescimento Neural/metabolismo , Neoplasias Cutâneas/tratamento farmacológico , Linfócitos T Citotóxicos/imunologia , Animais , Antineoplásicos Imunológicos/uso terapêutico , Fator Neurotrófico Derivado do Encéfalo/antagonistas & inibidores , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Humanos , Masculino , Melanoma/genética , Melanoma/imunologia , Melanoma/patologia , Camundongos , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Proteínas do Tecido Nervoso/antagonistas & inibidores , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/imunologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , RNA-Seq , Receptores de Fator de Crescimento Neural/antagonistas & inibidores , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/patologia , Linfócitos T Citotóxicos/metabolismo , Evasão Tumoral/genética , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/genética , Microambiente Tumoral/imunologia , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Front Immunol ; 11: 1784, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32849643

RESUMO

COVID-19 has recently become the most serious threat to public health, and its prevalence has been increasing at an alarming rate. The incubation period for the virus is ~1-14 days and all age groups may be susceptible to a fatality rate of about 5.9%. COVID-19 is caused by a novel single-stranded, positive (+) sense RNA beta coronavirus. The development of a vaccine for SARS-CoV-2 is an urgent need worldwide. Immunoinformatics approaches are both cost-effective and convenient, as in silico predictions can reduce the number of experiments needed. In this study, with the aid of immunoinformatics tools, we tried to design a multi-epitope vaccine that can be used for the prevention and treatment of COVID-19. The epitopes were computed by using B cells, cytotoxic T lymphocytes (CTL), and helper T lymphocytes (HTL) base on the proteins of SARS-CoV-2. A vaccine was devised by fusing together the B cell, HTL, and CTL epitopes with linkers. To enhance the immunogenicity, the ß-defensin (45 mer) amino acid sequence, and pan-HLA DR binding epitopes (13aa) were adjoined to the N-terminal of the vaccine with the help of the EAAAK linker. To enable the intracellular delivery of the modeled vaccine, a TAT sequence (11aa) was appended to C-terminal. Linkers play vital roles in producing an extended conformation (flexibility), protein folding, and separation of functional domains, and therefore, make the protein structure more stable. The secondary and three-dimensional (3D) structure of the final vaccine was then predicted. Furthermore, the complex between the final vaccine and immune receptors (toll-like receptor-3 (TLR-3), major histocompatibility complex (MHC-I), and MHC-II) were evaluated by molecular docking. Lastly, to confirm the expression of the designed vaccine, the mRNA of the vaccine was enhanced with the aid of the Java Codon Adaptation Tool, and the secondary structure was generated from Mfold. Then we performed in silico cloning. The final vaccine requires experimental validation to determine its safety and efficacy in controlling SARS-CoV-2 infections.


Assuntos
Betacoronavirus/química , Biologia Computacional/métodos , Infecções por Coronavirus/prevenção & controle , Epitopos de Linfócito B/imunologia , Epitopos de Linfócito T/imunologia , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Proteínas Virais/imunologia , Vacinas Virais/imunologia , Sequência de Aminoácidos , Infecções por Coronavirus/virologia , Antígenos HLA-DR/imunologia , Humanos , Imunogenicidade da Vacina , Simulação de Acoplamento Molecular , Pneumonia Viral/virologia , Dobramento de Proteína , Estrutura Terciária de Proteína , Linfócitos T Citotóxicos/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Vacinas de Subunidades/imunologia , beta-Defensinas/imunologia
7.
Ann Oncol ; 31(10): 1320-1335, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32745693

RESUMO

We established an international consortium to review and discuss relevant clinical evidence in order to develop expert consensus statements related to cancer management during the severe acute respiratory syndrome coronavirus 2-related disease (COVID-19) pandemic. The steering committee prepared 10 working packages addressing significant clinical questions from diagnosis to surgery. During a virtual consensus meeting of 62 global experts and one patient advocate, led by the European Society for Medical Oncology, statements were discussed, amended and voted upon. When consensus could not be reached, the panel revised statements until a consensus was reached. Overall, the expert panel agreed on 28 consensus statements that can be used to overcome many of the clinical and technical areas of uncertainty ranging from diagnosis to therapeutic planning and treatment during the COVID-19 pandemic.


Assuntos
Betacoronavirus , Consenso , Infecções por Coronavirus/terapia , Oncologia/normas , Neoplasias/terapia , Pneumonia Viral/terapia , Sociedades Médicas/normas , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/imunologia , Gerenciamento Clínico , Europa (Continente)/epidemiologia , Fator Estimulador de Colônias de Granulócitos/farmacologia , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Humanos , Oncologia/métodos , Neoplasias/epidemiologia , Neoplasias/imunologia , Pandemias/prevenção & controle , Pneumonia Viral/epidemiologia , Pneumonia Viral/imunologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Reação em Cadeia da Polimerase em Tempo Real/normas , Linfócitos T Citotóxicos/efeitos dos fármacos , Linfócitos T Citotóxicos/imunologia , Telemedicina/métodos , Telemedicina/normas
8.
PLoS Comput Biol ; 16(7): e1007972, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32658891

RESUMO

Although quantitative insights into the killing behaviour of Cytotoxic T Lymphocytes (CTLs) are necessary for the rational design of immune-based therapies, CTL killing function remains insufficiently characterised. One established model of CTL killing treats CTL cytotoxicity as a Poisson process, based on the assumption that CTLs serially kill antigen-presenting target cells via delivery of lethal hits, each lethal hit corresponding to a single injection of cytotoxic proteins into the target cell cytoplasm. Contradicting this model, a recent in vitro study of individual CTLs killing targets over a 12-hour period found significantly greater heterogeneity in CTL killing performance than predicted by Poisson-based killing. The observed killing process was dynamic and varied between CTLs, with the best performing CTLs exhibiting a marked increase in killing during the final hours of the experiments, along with a "burst killing" kinetic. Despite a search for potential differences between CTLs, no mechanistic explanation for the heterogeneous killing kinetics was found. Here we have used stochastic simulations to assess whether target cells might require multiple hits from CTLs before undergoing apoptosis, in order to verify whether multiple-hitting could explain the late onset, burst killing dynamics observed in vitro. We found that multiple-hitting from CTLs was entirely consistent with the observed killing kinetics. Moreover, the number of available targets and the spatiotemporal kinetics of CTL:target interactions influenced the realised CTL killing rate. We subsequently used realistic, spatial simulations to assess methods for estimating the hitting rate and the number of hits required for target death, to be applied to microscopy data of individual CTLs killing targets. We found that measuring the cumulative duration of individual contacts that targets have with CTLs would substantially improve accuracy when estimating the killing kinetics of CTLs.


Assuntos
Citoplasma/metabolismo , Processos Estocásticos , Linfócitos T Citotóxicos/citologia , Linfócitos T Citotóxicos/imunologia , Actinas/química , Algoritmos , Células Apresentadoras de Antígenos , Apoptose , Movimento Celular , Simulação por Computador , Citotoxicidade Imunológica , Humanos , Cinética , Funções Verossimilhança , Método de Monte Carlo , Distribuição de Poisson
9.
J Immunother Cancer ; 8(2)2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32727811

RESUMO

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic placed unprecedented pressure on various healthcare systems, including departments that use immunotherapies such as chimeric antigen receptor (CAR) T-cell therapy and immunosuppression therapy in organ transplantation units. The true impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection on immunocompromised CAR T-cell therapy recipients and kidney transplant recipients (KTRs) has not yet been established. CASE PRESENTATION: In this report, we compare two patients with severe COVID-19 pneumonia in either the humoral or cell-mediated immunodeficient states. The first patient was a man in his early 30s who was diagnosed with refractory multiple myeloma. He received fully humanized, anti-B-cell maturation antigen, CAR T-cell therapy before 4 months and achieved strict complete remission. He was infected with SARS-CoV-2 starting on January 26, 2019 and gradually progressed to severe pneumonia. Throughout the clinical progression of the disease, SARS-CoV-2 could not be cleared due to his humoral immunodeficient state. During this period of his severe COVID-19 pneumonia, elevated cytotoxic T-cells were observed in this patient's peripheral blood while elevated plasma levels of interleukin (IL)-2R, IL-6, tumor necrosis factor α, and ferritin were observed in his cytokine profiles. This patient eventually progressed into acute respiratory distress syndrome and recieved non-invasive ventilatory support. He failed to generate specific SARS-CoV-2 antibodies and died of respiratory failure on day 33 (d33). The second patient was a 52-year-old kidney transplant recipient (KTR) who took ciclosporin after renal transplantation for more than 7 years. He confirmed SARS-CoV-2 infection on January 20, 2019 and gradually progressed into severe pneumonia on d16 with a slightly elevated B-cell percentage and normal T-lymphocyte subsets. Viral clearance occurred together with the generation of specific anti-immunoglobulin G-SARS-CoV-2 antibodies after 2 weeks of treatment. He was symptom-free and discharged from the hospital on d42. CONCLUSION: We report a CAR T-cell therapy recipient diagnosed with COVID-19 for the first time. His virus clearance failure and life-threating cytokine storm during SARS-CoV-2 infection suggested that any decision to proceed CAR T-cell therapy during COVID-19 pandemics will require extensive discussion of potential risks and benefits. Immunosuppressant treatment based on ciclosporin could be relatively safe for KTRs diagnosed with COVID-19. TRIAL REGISTRATION NUMBER: ChiCTR-OPN-1800018137.


Assuntos
Betacoronavirus/imunologia , Infecções por Coronavirus/imunologia , Hospedeiro Imunocomprometido , Pneumonia Viral/imunologia , Linfócitos T Citotóxicos/imunologia , Adulto , Anticorpos Antivirais/metabolismo , Ciclosporina/uso terapêutico , Citocinas/metabolismo , Evolução Fatal , Humanos , Imunidade Celular , Imunidade Humoral , Masculino , Pessoa de Meia-Idade , Pandemias
10.
Cells ; 9(8)2020 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-32707842

RESUMO

The ectonucleotidases CD39 and CD73 regulate immune responses by balancing extracellular ATP and adenosine in inflammation and are likely to be involved in the pathophysiology of COVID-19. Here, we analyzed CD39 and CD73 on different lymphocyte populations in a small cohort of COVID-19 patients and in healthy individuals. We describe a significantly lower level of expression of CD73 on cytotoxic lymphocyte populations, including CD8+ T, natural killer T (NKT), and natural killer (NK) cells, during COVID-19. Interestingly, the decrease of CD73 on CD8+ T cells and NKT cells correlated with serum ferritin levels. Furthermore, we observed distinct functional differences between the CD73+ and CD73- subsets of CD8+ T cells and NKT cells with regard to cytokine/toxin secretion. In COVID-19 patients, the majority of the CD73-CD8+ T cells were capable of secreting granzyme B, perforin, tumor necrosis factor (TNF-α) or interferon-gamma (IFN-γ). To conclude, in this first study of CD39 and CD73 expression of lymphocytes in COVID-19, we show that CD8+ T cells and NKT cells lacking CD73 possess a significantly higher cytotoxic effector functionality compared to their CD73+ counterparts. Future studies should investigate differences of cellular CD39 and CD73 expression in patients at different disease stages and their potential as prognostic markers or targets for immunomodulatory therapies.


Assuntos
5'-Nucleotidase/metabolismo , Apirase/metabolismo , Infecções por Coronavirus/imunologia , Células Matadoras Naturais/imunologia , Células T Matadoras Naturais/imunologia , Pneumonia Viral/imunologia , Linfócitos T Citotóxicos/imunologia , Adenosina/metabolismo , Adulto , Idoso , Betacoronavirus , Infecções por Coronavirus/enzimologia , Feminino , Proteínas Ligadas por GPI/metabolismo , Granzimas/metabolismo , Humanos , Inflamação/enzimologia , Inflamação/imunologia , Interferon gama/metabolismo , Masculino , Pessoa de Meia-Idade , Pandemias , Perforina/metabolismo , Pneumonia Viral/enzimologia , Transdução de Sinais/imunologia , Linfócitos T Citotóxicos/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
11.
Cancer Immunol Immunother ; 69(10): 2157-2162, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32638080

RESUMO

Epidemiological evidence suggests that females have an advantage over males in cases of melanoma incidence, progression, and survival. However, the biological mechanisms underlying these sex differences remain unclear. With the knowledge that females generally have a more robust immune system than males, we investigated sex differences in melanoma progression in a B16-F10/BL6 syngeneic mouse model. We observed significantly less tumor volume and growth rate over 14 days in female mice compared to male mice. Furthermore, higher populations of CD4+ and CD8+ T cells, which indicate adaptive immune responses, were found in the circulating blood and tumors of females and corresponded with less tumor growth, and vice versa in males. Our results highlight a mouse model that represents melanoma progression in the human population and displays a higher immune response to melanoma in females compared to males. These findings suggest that the immune system may be one of the mechanisms responsible for sex differences in melanoma.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Modelos Animais de Doenças , Linfócitos do Interstício Tumoral/imunologia , Melanoma Experimental/imunologia , Neoplasias Cutâneas/imunologia , Linfócitos T Citotóxicos/imunologia , Animais , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/patologia , Feminino , Masculino , Melanoma Experimental/patologia , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias Cutâneas/secundário , Linfócitos T Citotóxicos/patologia , Carga Tumoral , Células Tumorais Cultivadas
12.
Nature ; 585(7823): 107-112, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32728218

RESUMO

Treating patients who have cancer with vaccines that stimulate a targeted immune response is conceptually appealing, but cancer vaccine trials have not been successful in late-stage patients with treatment-refractory tumours1,2. We are testing melanoma FixVac (BNT111)-an intravenously administered liposomal RNA (RNA-LPX) vaccine, which targets four non-mutated, tumour-associated antigens that are prevalent in melanoma-in an ongoing, first-in-human, dose-escalation phase I trial in patients with advanced melanoma (Lipo-MERIT trial, ClinicalTrials.gov identifier NCT02410733). We report here data from an exploratory interim analysis that show that melanoma FixVac, alone or in combination with blockade of the checkpoint inhibitor PD1, mediates durable objective responses in checkpoint-inhibitor (CPI)-experienced patients with unresectable melanoma. Clinical responses are accompanied by the induction of strong CD4+ and CD8+ T cell immunity against the vaccine antigens. The antigen-specific cytotoxic T-cell responses in some responders reach magnitudes typically reported for adoptive T-cell therapy, and are durable. Our findings indicate that RNA-LPX vaccination is a potent immunotherapy in patients with CPI-experienced melanoma, and suggest the general utility of non-mutant shared tumour antigens as targets for cancer vaccination.


Assuntos
Antineoplásicos/uso terapêutico , Vacinas Anticâncer/genética , Vacinas Anticâncer/imunologia , Melanoma/imunologia , Melanoma/terapia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , RNA Neoplásico/genética , Linfócitos T/imunologia , Antígenos de Neoplasias/imunologia , Antineoplásicos/farmacologia , Vacinas Anticâncer/administração & dosagem , Vacinas Anticâncer/efeitos adversos , Terapia Combinada , Humanos , Melanoma/tratamento farmacológico , Melanoma/patologia , Estadiamento de Neoplasias , Linfócitos T/citologia , Linfócitos T Citotóxicos/citologia , Linfócitos T Citotóxicos/imunologia , Vacinação
13.
Proc Natl Acad Sci U S A ; 117(31): 18638-18648, 2020 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-32665435

RESUMO

Vγ9Vδ2 T cells are a major human blood γδ T cell population that respond in a T cell receptor (TCR)-dependent manner to phosphoantigens which are generated by a variety of microorganisms. It is not clear how Vγ9Vδ2 T cells react toward the sudden microbial exposure early after birth. We found that human Vγ9Vδ2 T cells with a public/shared fetal-derived TCR repertoire expanded within 10 wk postpartum. Such an expansion was not observed in non-Vγ9Vδ2 γδ T cells, which possessed a private TCR repertoire. Furthermore, only the Vγ9Vδ2 T cells differentiated into potent cytotoxic effector cells by 10 wk of age, despite their fetal origin. Both the expansion of public fetal Vγ9Vδ2 T cells and their functional differentiation were not affected by newborn vaccination with the phosphoantigen-containing bacillus Calmette-Guérin (BCG) vaccine. These findings suggest a strong and early priming of the public fetal-derived Vγ9Vδ2 T cells promptly after birth, likely upon environmental phosphoantigen exposure.


Assuntos
Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Subpopulações de Linfócitos T/imunologia , Linfócitos T Citotóxicos/imunologia , Vacina BCG/imunologia , Células Cultivadas , Citocinas/metabolismo , Feminino , Feto/imunologia , Humanos , Lactente , Recém-Nascido , Gravidez
14.
Clin Immunol ; 218: 108516, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32574709

RESUMO

BACKGROUND: Coronavirus disease 2019 (COVID-19) is posing a huge threat to human health worldwide. We aim to investigate the immune status of CD8+ T and NK cells in COVID-19 patients. METHODS: The count and immune status of lymphocytes were detected by flow cytometry in 32 COVID-19 patients and 18 healthy individuals. RESULTS: As the disease progression in COVID-19 patients, CD8+ T and NK cells were significantly decreased in absolute number but highly activated. After patients' condition improved, the count and immune status of CD8+ T and NK cells restored to some extent. GrA+CD8+ T and perforin+ NK cells had good sensitivity and specificity for assisting diagnosis of COVID-19. CONCLUSIONS: As the disease progression, the declined lymphocytes in COVID-19 patients might lead to compensatory activation of CD8+ T and NK cells. GrA+CD8+ T and perforin+ NK cells might be used as meaningful indicators for assisting diagnosis of COVID-19.


Assuntos
Betacoronavirus/patogenicidade , Infecções por Coronavirus/diagnóstico , Granzimas/genética , Células Matadoras Naturais/imunologia , Perforina/genética , Pneumonia Viral/diagnóstico , Linfócitos T Citotóxicos/imunologia , Idoso , Idoso de 80 Anos ou mais , Betacoronavirus/imunologia , Biomarcadores/sangue , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD4-Positivos/virologia , Estudos de Casos e Controles , China , Técnicas de Laboratório Clínico/métodos , Infecções por Coronavirus/sangue , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/patologia , Progressão da Doença , Feminino , Expressão Gênica , Granzimas/sangue , Granzimas/imunologia , Humanos , Células Matadoras Naturais/patologia , Células Matadoras Naturais/virologia , Ativação Linfocitária , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Pandemias , Perforina/sangue , Perforina/imunologia , Pneumonia Viral/sangue , Pneumonia Viral/imunologia , Pneumonia Viral/patologia , Prognóstico , Curva ROC , Índice de Gravidade de Doença , Linfócitos T Citotóxicos/patologia , Linfócitos T Citotóxicos/virologia
16.
Int J Infect Dis ; 97: 313-321, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32492530

RESUMO

OBJECTIVES: We hypothesized that immune response may contribute to progression of coronavirus disease-19 (COVID-19) at the second week of illness. Therefore, we compared cell-mediated immune (CMI) responses between severe and mild COVID-19 cases. METHODS: We examined peripheral blood mononuclear cells of laboratory-confirmed COVID-19 patients from their first and third weeks of illness. Severe pneumonia was defined as an oxygen saturation ≤93% at room air. Expressions of molecules related to T-cell activation and functions were analyzed by flow cytometry. RESULTS: The population dynamics of T cells at the first week were not different between the two groups. However, total numbers of CD4+ and CD8+ T cells tended to be lower in the severe group at the third week of illness. Expressions of Ki-67, PD-1, perforin, and granzyme B in CD4+ or CD8+ T cells were significantly higher in the severe group than in the mild group at the third week. In contrast to the mild group, the levels of their expression did not decrease in the severe group. CONCLUSIONS: Severe COVID-19 had a higher degree of proliferation, activation, and cytotoxicity of T-cells at the late phase of illness without cytotoxic T-cell contraction, which might contribute to the development of severe COVID-19.


Assuntos
Infecções por Coronavirus/imunologia , Imunidade Celular , Ativação Linfocitária , Pneumonia Viral/imunologia , Linfócitos T Citotóxicos/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Betacoronavirus , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Infecções por Coronavirus/fisiopatologia , Citocinas/imunologia , Feminino , Granzimas , Humanos , Antígeno Ki-67 , Leucócitos Mononucleares/imunologia , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Pandemias , Perforina , Pneumonia Viral/fisiopatologia , Receptor de Morte Celular Programada 1
17.
Nature ; 583(7814): 127-132, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32555459

RESUMO

Cellular senescence is characterized by stable cell-cycle arrest and a secretory program that modulates the tissue microenvironment1,2. Physiologically, senescence serves as a tumour-suppressive mechanism that prevents the expansion of premalignant cells3,4 and has a beneficial role in wound-healing responses5,6. Pathologically, the aberrant accumulation of senescent cells generates an inflammatory milieu that leads to chronic tissue damage and contributes to diseases such as liver and lung fibrosis, atherosclerosis, diabetes and osteoarthritis1,7. Accordingly, eliminating senescent cells from damaged tissues in mice ameliorates the symptoms of these pathologies and even promotes longevity1,2,8-10. Here we test the therapeutic concept that chimeric antigen receptor (CAR) T cells that target senescent cells can be effective senolytic agents. We identify the urokinase-type plasminogen activator receptor (uPAR)11 as a cell-surface protein that is broadly induced during senescence and show that uPAR-specific CAR T cells efficiently ablate senescent cells in vitro and in vivo. CAR T cells that target uPAR extend the survival of mice with lung adenocarcinoma that are treated with a senescence-inducing combination of drugs, and restore tissue homeostasis in mice in which liver fibrosis is induced chemically or by diet. These results establish the therapeutic potential of senolytic CAR T cells for senescence-associated diseases.


Assuntos
Envelhecimento/patologia , Senescência Celular/imunologia , Cirrose Hepática/terapia , Longevidade/imunologia , Neoplasias Pulmonares/terapia , Receptores de Antígenos Quiméricos/imunologia , Rejuvenescimento , Linfócitos T/imunologia , Adenocarcinoma/imunologia , Adenocarcinoma/patologia , Adenocarcinoma/terapia , Animais , Tetracloreto de Carbono , Feminino , Xenoenxertos , Humanos , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/imunologia , Cirrose Hepática/patologia , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Receptores de Antígenos Quiméricos/metabolismo , Receptores de Ativador de Plasminogênio Tipo Uroquinase/genética , Receptores de Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Linfócitos T/metabolismo , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/metabolismo
18.
Vaccine ; 38(28): 4464-4475, 2020 06 09.
Artigo em Inglês | MEDLINE | ID: covidwho-133338

RESUMO

The 2013-2016 West Africa EBOV epidemic was the biggest EBOV outbreak to date. An analysis of virus-specific CD8+ T-cell immunity in 30 survivors showed that 26 of those individuals had a CD8+ response to at least one EBOV protein. The dominant response (25/26 subjects) was specific to the EBOV nucleocapsid protein (NP). It has been suggested that epitopes on the EBOV NP could form an important part of an effective T-cell vaccine for Ebola Zaire. We show that a 9-amino-acid peptide NP44-52 (YQVNNLEEI) located in a conserved region of EBOV NP provides protection against morbidity and mortality after mouse adapted EBOV challenge. A single vaccination in a C57BL/6 mouse using an adjuvanted microsphere peptide vaccine formulation containing NP44-52 is enough to confer immunity in mice. Our work suggests that a peptide vaccine based on CD8+ T-cell immunity in EBOV survivors is conceptually sound and feasible. Nucleocapsid proteins within SARS-CoV-2 contain multiple Class I epitopes with predicted HLA restrictions consistent with broad population coverage. A similar approach to a CTL vaccine design may be possible for that virus.


Assuntos
Desenho de Fármacos , Vacinas contra Ebola/imunologia , Epitopos de Linfócito T/imunologia , Proteínas do Nucleocapsídeo/imunologia , Linfócitos T Citotóxicos/imunologia , Vacinas de Subunidades/imunologia , Vacinas Virais , Sequência de Aminoácidos , Animais , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Modelos Animais de Doenças , Vacinas contra Ebola/química , Epitopos de Linfócito T/química , Doença pelo Vírus Ebola/imunologia , Doença pelo Vírus Ebola/prevenção & controle , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Proteínas do Nucleocapsídeo/química , Pandemias/prevenção & controle , Pneumonia Viral/imunologia , Pneumonia Viral/prevenção & controle , Vacinas de Subunidades/química , Vacinas Virais/química , Vacinas Virais/imunologia
19.
Vaccine ; 38(28): 4464-4475, 2020 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-32418793

RESUMO

The 2013-2016 West Africa EBOV epidemic was the biggest EBOV outbreak to date. An analysis of virus-specific CD8+ T-cell immunity in 30 survivors showed that 26 of those individuals had a CD8+ response to at least one EBOV protein. The dominant response (25/26 subjects) was specific to the EBOV nucleocapsid protein (NP). It has been suggested that epitopes on the EBOV NP could form an important part of an effective T-cell vaccine for Ebola Zaire. We show that a 9-amino-acid peptide NP44-52 (YQVNNLEEI) located in a conserved region of EBOV NP provides protection against morbidity and mortality after mouse adapted EBOV challenge. A single vaccination in a C57BL/6 mouse using an adjuvanted microsphere peptide vaccine formulation containing NP44-52 is enough to confer immunity in mice. Our work suggests that a peptide vaccine based on CD8+ T-cell immunity in EBOV survivors is conceptually sound and feasible. Nucleocapsid proteins within SARS-CoV-2 contain multiple Class I epitopes with predicted HLA restrictions consistent with broad population coverage. A similar approach to a CTL vaccine design may be possible for that virus.


Assuntos
Desenho de Fármacos , Vacinas contra Ebola/imunologia , Epitopos de Linfócito T/imunologia , Proteínas do Nucleocapsídeo/imunologia , Linfócitos T Citotóxicos/imunologia , Vacinas de Subunidades/imunologia , Vacinas Virais , Sequência de Aminoácidos , Animais , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Modelos Animais de Doenças , Vacinas contra Ebola/química , Epitopos de Linfócito T/química , Doença pelo Vírus Ebola/imunologia , Doença pelo Vírus Ebola/prevenção & controle , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Proteínas do Nucleocapsídeo/química , Pandemias/prevenção & controle , Pneumonia Viral/imunologia , Pneumonia Viral/prevenção & controle , Vacinas de Subunidades/química , Vacinas Virais/química , Vacinas Virais/imunologia
20.
PLoS Pathog ; 16(5): e1008244, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32365082

RESUMO

Viral escape from CD8+ cytotoxic T lymphocyte responses correlates with disease progression and represents a significant challenge for vaccination. Here, we demonstrate that CD8+ T cell recognition of the naturally occurring MHC-I-restricted LCMV-associated immune escape variant Y4F is restored following vaccination with a proline-altered peptide ligand (APL). The APL increases MHC/peptide (pMHC) complex stability, rigidifies the peptide and facilitates T cell receptor (TCR) recognition through reduced entropy costs. Structural analyses of pMHC complexes before and after TCR binding, combined with biophysical analyses, revealed that although the TCR binds similarly to all complexes, the p3P modification alters the conformations of a very limited amount of specific MHC and peptide residues, facilitating efficient TCR recognition. This approach can be easily introduced in peptides restricted to other MHC alleles, and can be combined with currently available and future vaccination protocols in order to prevent viral immune escape.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Vírus da Coriomeningite Linfocítica/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Animais , Antivirais/metabolismo , Linfócitos T CD8-Positivos/fisiologia , Proteínas de Ligação a DNA/imunologia , Epitopos/imunologia , Epitopos de Linfócito T/imunologia , Genes RAG-1/imunologia , Ligantes , Ativação Linfocitária/imunologia , Vírus da Coriomeningite Linfocítica/genética , Vírus da Coriomeningite Linfocítica/patogenicidade , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Peptídeos/metabolismo , Prolina/metabolismo , Ligação Proteica , Linfócitos T Citotóxicos/imunologia , Vacinação/métodos
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