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1.
Front Immunol ; 12: 728936, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34484239

RESUMO

The use of minimal peptide sets offers an appealing alternative for design of vaccines and T cell diagnostics compared to conventional whole protein approaches. T cell immunogenicity towards peptides is contingent on binding to human leukocyte antigen (HLA) molecules of the given individual. HLA is highly polymorphic, and each variant typically presents a different repertoire of peptides. This polymorphism combined with pathogen diversity challenges the rational selection of peptide sets with broad immunogenic potential and population coverage. Here we propose PopCover-2.0, a simple yet highly effective method, for resolving this challenge. The method takes as input a set of (predicted) CD8 and/or CD4 T cell epitopes with associated HLA restriction and pathogen strain annotation together with information on HLA allele frequencies, and identifies peptide sets with optimal pathogen and HLA (class I and II) coverage. PopCover-2.0 was benchmarked on historic data in the context of HIV and SARS-CoV-2. Further, the immunogenicity of the selected SARS-CoV-2 peptides was confirmed by experimentally validating the peptide pools for T cell responses in a panel of SARS-CoV-2 infected individuals. In summary, PopCover-2.0 is an effective method for rational selection of peptide subsets with broad HLA and pathogen coverage. The tool is available at https://services.healthtech.dtu.dk/service.php?PopCover-2.0.


Assuntos
Epitopos de Linfócito T/imunologia , Antígenos HLA/genética , Antígenos HLA/imunologia , Peptídeos/imunologia , Alelos , Alergia e Imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , COVID-19/imunologia , COVID-19/prevenção & controle , Genótipo , Antígenos HLA/classificação , Humanos , Imunogenicidade da Vacina , Técnicas Imunológicas , Peptídeos/classificação , SARS-CoV-2/imunologia
2.
J Transl Med ; 19(1): 378, 2021 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-34488776

RESUMO

BACKGROUND: Neuroinflammation has been proved to play a role in dopaminergic neuronal death in Parkinson's disease (PD). This link highlights the relevance of the immune response in the progression of the disease. However, little is known about the impact of peripheral immune response on the disease. This study is aimed to evaluate how immune cell populations change in untreated PD patients followed-up for 2 years. METHODS: Thirty-two patients with no previous treatment (PD-0 yr) and twenty-two healthy subjects (controls) were included in the study. PD patients were sampled 1 and 2 years after the start of the treatment. CD4 T cells (naïve/central memory, effector, and activated), CD8 T cells (activated, central memory, effector memory, NKT, Tc1, Tc2, and Tc17), and B cells (activated, plasma, and Lip-AP) were characterized by flow cytometry. RESULTS: We observed decreased levels of naïve/central memory CD4 and CD8 T cells, Tc1, Tc2, NKT, and plasma cells, and increased levels of effector T cells, activated T cells, and Tc17. CONCLUSIONS: PD patients treated for 2 years showed an imbalance in the naive/effector immune response. Naïve and effector cell levels were associated with clinical deterioration. These populations are also correlated to aging. On the other hand, higher Tc17 levels suggest an increased inflammatory response, which may impact the progression of the disease. Our results highlight the relevant effect of treatment on the immune response, which could improve our management of the disease.


Assuntos
Doença de Parkinson , Linfócitos T CD4-Positivos , Linfócitos T CD8-Positivos , Estudos de Casos e Controles , Humanos , Imunidade
3.
Elife ; 102021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34468313

RESUMO

The factors which drive and control disease progression can be inferred from mathematical models that integrate measures of immune responses, data from tissue sampling and markers of infection dynamics.


Assuntos
Infecções por Orthomyxoviridae , Linfócitos T CD8-Positivos , Humanos
4.
Rev Med Chil ; 149(2): 255-262, 2021 Feb.
Artigo em Espanhol | MEDLINE | ID: mdl-34479271

RESUMO

Even though the mechanisms that mediate essential hypertension (HT) are not fully understood, an immunological-inflammatory mechanism could be the common pathway for diverse pathophysiological mechanisms. We analyze in a simplified way the participation of the immune system in HT. T lymphocytes (TL) and antigen presenting cells (APCs) are components of the immune system capable of generating proinflammatory cytokines. They cause endothelial damage, vasoconstriction, and decreased urinary sodium excretion. CD4+ and CD8+ TL are effector cells, causally implicated in the development of HT, whereas type γδ TL play their pathogenic role in HT enhancing endothelial dysfunction. Additionally, a immunomodulation decrease by regulatory TL, worsens endothelial dysfunction and reduces vasodilation in experimental HT. Results of recent studies indicate that lymphocyte activation would be mediated by antigens captured by antigen APCs for subsequent presentation to "naive" TL. On the other hand, proinflammatory states such as obesity, the change of the intestinal microbiota and the increase in salt intake favors TL and APC activation, contributing to HT development.


Assuntos
Hipertensão , Ativação Linfocitária , Linfócitos T CD8-Positivos , Humanos , Inflamação , Linfócitos T Reguladores
5.
Signal Transduct Target Ther ; 6(1): 328, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34471088

RESUMO

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


Assuntos
Linfócitos T CD8-Positivos/imunologia , COVID-19/imunologia , Microambiente Celular/imunologia , Pulmão/imunologia , Receptores CXCR3/imunologia , SARS-CoV-2/imunologia , Enzima de Conversão de Angiotensina 2/imunologia , Animais , Linfócitos T CD8-Positivos/patologia , COVID-19/patologia , Modelos Animais de Doenças , Inflamação/imunologia , Inflamação/patologia , Interferon-alfa/imunologia , Interleucina-6/imunologia , Pulmão/patologia , Pulmão/virologia , Macaca mulatta , Masculino
6.
Nat Commun ; 12(1): 5209, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34471106

RESUMO

TGF-ß is secreted in the tumour microenvironment in a latent, inactive form bound to latency associated protein and activated by the integrin αV subunit. The activation of latent TGF-ß by cancer-cell-expressed αV re-shapes the tumour microenvironment, and this could affect patient responses to PD-1-targeting therapy. Here we show, using multiplex immunofluorescence staining in cohorts of anti-PD-1 and anti-PD-L1-treated lung cancer patients, that decreased expression of cancer cell αV is associated with improved immunotherapy-related, progression-free survival, as well as with an increased density of CD8+CD103+ tumour-infiltrating lymphocytes. Mechanistically, tumour αV regulates CD8 T cell recruitment, induces CD103 expression on activated CD8+ T cells and promotes their differentiation to granzyme B-producing CD103+CD69+ resident memory T cells via autocrine TGF-ß signalling. Thus, our work provides the underlying principle of targeting cancer cell αV for more efficient PD-1 checkpoint blockade therapy.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Integrina alfaV/metabolismo , Receptor de Morte Celular Programada 1/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Animais , Antígenos CD , Antígeno B7-H1 , Linhagem Celular Tumoral , Feminino , Humanos , Imunoterapia , Cadeias alfa de Integrinas , Neoplasias Pulmonares/tratamento farmacológico , Linfócitos do Interstício Tumoral/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Microambiente Tumoral
7.
Anal Chim Acta ; 1179: 338820, 2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34535251

RESUMO

The number of CD8+ T lymphocytes (CD8 cells) in peripheral blood can directly reflect the immune status of the body and is widely used for auxiliary diagnosis and prognostic evaluation of diseases. There is an urgent need to develop a simple CD8 cell-counting platform to meet clinical needs. Our group designed a paper-based cell-counting method based on a blocking competition strategy. In addition, we developed a time-resolved fluorescence-blocking competitive lateral flow immunoassay (TRF-BCLFIA) for point-of-care CD8 cell counting that functions by measuring europium nanoparticle (EuNP)-labeled CD8 antibody probes that are not captured by CD8 cells, and we indirectly calculated the concentration of CD8 cells in samples. Within 30 min, four operation steps can provide an accurate CD8 cell count for a 75-µL whole-blood sample, and this approach can be implemented on a handheld device. The TRF-BCLFIA reliably quantified CD8 cells in whole-blood samples, in which the assay exhibited a linear correlation (R2 = 0.989) readout for CD8 cell concentrations ranging from 137 to 821 cells/µL. To validate this approach, our newly developed CD8 cell-counting tool was used to assess 33 tumor patient blood samples. The results showed a high consistency with a flow cytometry-based absolute count. This analysis approach is a promising alternative for the costly standard flow cytometry-based tools for CD8 cell counting in tumor patients in community clinics, small hospitals, and low medical resource regions. This technology would deliver simple diagnostics to patients anywhere in the world, regardless of geography or socioeconomic status.


Assuntos
Európio , Nanopartículas Metálicas , Linfócitos T CD8-Positivos , Citometria de Fluxo , Fluorimunoensaio , Humanos
8.
Nat Commun ; 12(1): 4854, 2021 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-34381049

RESUMO

Multisystem inflammatory syndrome in children (MIS-C) presents with fever, inflammation and pathology of multiple organs in individuals under 21 years of age in the weeks following severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Although an autoimmune pathogenesis has been proposed, the genes, pathways and cell types causal to this new disease remain unknown. Here we perform RNA sequencing of blood from patients with MIS-C and controls to find disease-associated genes clustered in a co-expression module annotated to CD56dimCD57+ natural killer (NK) cells and exhausted CD8+ T cells. A similar transcriptome signature is replicated in an independent cohort of Kawasaki disease (KD), the related condition after which MIS-C was initially named. Probing a probabilistic causal network previously constructed from over 1,000 blood transcriptomes both validates the structure of this module and reveals nine key regulators, including TBX21, a central coordinator of exhausted CD8+ T cell differentiation. Together, this unbiased, transcriptome-wide survey implicates downregulation of NK cells and cytotoxic T cell exhaustion in the pathogenesis of MIS-C.


Assuntos
Linfócitos T CD8-Positivos/imunologia , COVID-19/imunologia , Síndrome de Resposta Inflamatória Sistêmica/imunologia , Transcriptoma/imunologia , Adolescente , Antígeno CD56/metabolismo , Antígenos CD57/metabolismo , Linfócitos T CD8-Positivos/metabolismo , COVID-19/genética , Criança , Pré-Escolar , Regulação para Baixo , Feminino , Humanos , Lactente , Recém-Nascido , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Masculino , Síndrome de Linfonodos Mucocutâneos/genética , Síndrome de Linfonodos Mucocutâneos/imunologia , SARS-CoV-2/patogenicidade , Síndrome de Resposta Inflamatória Sistêmica/genética , Adulto Jovem
9.
Exp Gerontol ; 153: 111504, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34343632

RESUMO

PURPOSE: To evaluate the effects of functional and concurrent training on immune function and functional fitness in postmenopausal women. MATERIALS AND METHODS: A randomized controlled trial was performed on 108 women aged 60 or older who were randomly assigned among the groups: control group (CG: n = 40; 63.88 ± 3.64 years); functional training (FT: n = 32; 63.88 ± 3.79 years); and concurrent training (CT: n = 36; 64.83 ± 4.00 years). Immune function was measured by the expression of the T-lymphocyte function-related surface markers (CD28 and CD57). Functional fitness was assessed using physical tests similar to daily activities, i.e., five times sit to stand, timed up and go, and gallon-jug shelf-transfer. RESULTS: Regarding immune function, there was only a time effect, without between-group differences. Specifically, FT and CT show a reduction and increase in CD4+ and CD8+ T cells, respectively, without impairment in the subpopulations analyzed, while CG showed a reduction in naive T cells (CD8+CD28+). For functional fitness tests, there was a time × group interaction effect for all tests, the FT and CT were superior to the CG, with FT showing differences after the fourth week, while the CT showed this effect after the eighth week of intervention. CONCLUSION: FT and CT do not impair immune function and similarly improve functional fitness in postmenopausal women. CLINICAL TRIALS REGISTRY: RBR-2d56bt.


Assuntos
Linfócitos T CD8-Positivos , Pós-Menopausa , Exercício Físico , Feminino , Humanos , Imunidade , Aptidão Física
10.
Vaccine ; 39(36): 5173-5186, 2021 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-34353682

RESUMO

Zika virus (ZIKV) caused over two million human infections in more than 80 countries around 2015-2016. Current vaccines under development are mostly focused on inducing antibodies that despite capable of inhibiting the virus, may have the potential to trigger antibody dependent enhancement (ADE). T cell vaccines that do not induce antibodies targeting viral surface will unlikely cause ADE, but be capable of potentiating the effectiveness of an antibody-inducing vaccine. To develop such a protective T cell vaccine, we first examined the repertoire of antigen-specific T cells in immunocompetent mice that have been transiently infected by ZIKV. Through epitope mapping using 427 overlapping peptides spanning the entire length of ZIKV polyprotein, we discovered 27 immunodominant epitopes scattered throughout the virus on C, E, NS1-NS5 proteins. Among them, 8 were confirmed as CD4+ T cell epitopes, and 16 as CD8+ T cell epitopes, while 3 for both T cell subsets. From these 27 newly identified epitopes, the top 10 epitopes were selected to formulate three T cell vaccines comprised of either CD4+ T cell epitopes, or CD8+ T cell epitopes, or a mixture of both. Immunization with these T cell epitopes induced T cell-mediated cytotoxicity and cytokine production, and conferred varying degrees of protection against ZIKV challenge. Moreover, these new T cell vaccines also improved the protective efficacy of a neutralizing antibody-inducing recombinant E80 protein vaccine. Together, our results provided additional evidence in support of the protective role of ZIKV-specific CD4+ and CD8+ T cells, and laid foundation for future development of T cell vaccines for ZIKV.


Assuntos
Infecção por Zika virus , Zika virus , Animais , Anticorpos Neutralizantes , Anticorpos Antivirais , Linfócitos T CD4-Positivos , Linfócitos T CD8-Positivos , Mapeamento de Epitopos , Epitopos de Linfócito T , Epitopos Imunodominantes , Camundongos , Vacinas Sintéticas , Infecção por Zika virus/prevenção & controle
11.
Immunity ; 54(8): 1630-1632, 2021 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-34380061

RESUMO

The nature of the epitopes recognized by tumor-infiltrating T cells is not clearly defined. In this issue of Immunity, Cheng et al. demonstrate that tissue-resident memory CD8+ T cells specific for hepatitis B virus-derived antigens exhibit potent anti-tumor properties and correlate with relapse-free survival in patients with resected hepatocellular carcinoma.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Linfócitos T CD8-Positivos , Vírus da Hepatite B , Humanos , Recidiva Local de Neoplasia
12.
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
14.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 29(4): 1360-1364, 2021 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-34362531

RESUMO

The incidence of hematological malignant tumor is increasing year by year, and seriously affecting the human health. In addition to the traditional radiation and chemotherapy, immunotherapy has achieved a certain effect in the treatment of blood tumor, but it is limited by exhaustion of CD8+ T cell. The exhaustion of CD8+ T cells is mainly related to the activation of some immune checkpoint inhibitors, such as (Tim3), programmed death 1 (PD-1), cytotoxic T-lymphocyte-associated protein 4 (CTLA-4), etc. Among them, Tim3 is getting more and more attention. The combination of Tim3 and its ligand galectin-9 produced a strong cellular immunosuppressive effect. Tim3 has been proved to be associated with CD8+ T cell exhaustion in many tumors. In this review, the application of Tim3/galectin-9 in hematologic tumors is briefly summarized so as to provide theoretical basis for clinical diagnosis and treatment of these diseases.


Assuntos
Neoplasias Hematológicas , Receptor Celular 2 do Vírus da Hepatite A , Linfócitos T CD8-Positivos , Galectinas , Humanos , Imunoterapia
15.
Georgian Med News ; (315): 152-159, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34365442

RESUMO

Different studies indicate that tumor infiltrating lymphocytes (TILs) and tumor associated neutrophils (TANs) play an important role during the progression of malignant tumors. We have analysed the distribution of tumor associated neutrophils (TANs) and tumor infiltrating lymphocytes (TILs) in different conjunctival lesions, with different proliferation and apoptotic characteristics. The distribution of TILs and TANs were evaluated in standard haematoxylin and eosin (H&E) stained sections using the digital pathology software QuPathin normal conjunctiva, actinic keratosis, pterigea, conjunctival intraepithelial neoplasias (CoIN1-3) and conjunctival squamous cell carcinoma (CSCC). In addition, the expression of following markers were investigated using standard immunohistochemistry: Ki67, Bcl2, p53, CD3, CD8 and Foxp3. The study results indicated that the number of TILs and TANs are significantly increased during the progression of conjunctival intraepithelial lesions. Also, the number of TILs and TANs significantly correlate with higher proliferation index, lower apoptotic index and the p53 mutation status.


Assuntos
Neoplasias da Mama , Linfócitos do Interstício Tumoral , Linfócitos T CD8-Positivos , Proliferação de Células , Feminino , Humanos , Imuno-Histoquímica , Prognóstico , Microambiente Tumoral
17.
Cell Rep ; 36(6): 109518, 2021 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-34358460

RESUMO

We describe severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-specific T cell responses, soluble markers of inflammation, and antibody levels and neutralization capacity longitudinally in 70 individuals with PCR-confirmed SARS-CoV-2 infection. Participants represent a spectrum of illness and recovery, including some with persistent viral shedding in saliva and many experiencing post-acute sequelae of SARS-CoV-2 infection (PASC). T cell responses remain stable for up to 9 months. Whereas the magnitude of early CD4+ T cell immune responses correlates with severity of initial infection, pre-existing lung disease is independently associated with higher long-term SARS-CoV-2-specific CD8+ T cell responses. Among participants with PASC 4 months following coronavirus disease 2019 (COVID-19) symptom onset, we observe a lower frequency of CD8+ T cells expressing CD107a, a marker of degranulation, in response to Nucleocapsid (N) peptide pool stimulation, and a more rapid decline in the frequency of N-specific interferon-γ-producing CD8+ T cells. Neutralizing antibody levels strongly correlate with SARS-CoV-2-specific CD4+ T cell responses.


Assuntos
COVID-19/complicações , COVID-19/imunologia , SARS-CoV-2/imunologia , Adulto , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Linfócitos T CD8-Positivos/imunologia , COVID-19/patologia , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Eliminação de Partículas Virais/imunologia
19.
Viruses ; 13(8)2021 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-34452355

RESUMO

BACKGROUND: New coronavirus SARS-CoV-2, a causative agent of the COVID-19 pandemic, has been circulating among humans since November 2019. Multiple studies have assessed the qualitative and quantitative characteristics of virus-specific immunity in COVID-19 convalescents, however, some aspects of the development of memory T-cell responses after natural SARS-CoV-2 infection remain uncovered. METHODS: In most of published studies T-cell immunity to the new coronavirus is assessed using peptides corresponding to SARS-CoV-1 or SARS-CoV-2 T-cell epitopes, or with peptide pools covering various parts of the viral proteins. Here, we determined the level of CD4+ and CD8+ memory T-cell responses in COVID-19 convalescents by stimulating PBMCs collected 1 to 6 months after recovery with sucrose gradient-purified live SARS-CoV-2. IFNγ production by the central and effector memory helper and cytotoxic T cells was assessed by intracellular cytokine staining assay and flow cytometry. RESULTS: Stimulation of PBMCs with live SARS-CoV-2 revealed IFNγ-producing T-helper effector memory cells with CD4+CD45RA-CCR7- phenotype, which persisted in circulation for up to 6 month after COVID-19. In contrast, SARS-CoV-2-specific IFNγ-secreting cytotoxic effector memory T cells were found at significant levels only shortly after the disease, but rapidly decreased over time. CONCLUSION: The stimulation of immune cells with live SARS-CoV-2 revealed a rapid decline in the pool of effector memory CD8+, but not CD4+, T cells after recovery from COVID-19. These data provide additional information on the development and persistence of cellular immune responses after natural infection, and can inform further development of T cell-based SARS-CoV-2 vaccines.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , COVID-19/imunologia , Memória Imunológica , Interferon gama/imunologia , Leucócitos Mononucleares/imunologia , SARS-CoV-2/imunologia , COVID-19/virologia , Epitopos de Linfócito T/imunologia , Humanos , Leucócitos Mononucleares/virologia , SARS-CoV-2/genética , SARS-CoV-2/fisiologia , Linfócitos T Citotóxicos/imunologia
20.
Egypt J Immunol ; 28(3): 157-167, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34453787

RESUMO

NK group 2 member A (NKG2A) receptor transduces inhibitory signaling; suppressing NK and T-cell cytokine secretion and cytotoxic function. This study aimed to assess the expression of NKG2A inhibitory receptor on natural killer (NK) cells and CD8+ T lymphocytes in COVID-19 patients and correlate the results with disease severity defined according to the criteria established by the world health organization, in a trial to understand the immunological response towards COVID-19 infection. The study enrolled 30 COVID-19 patients classified into 2 groups that comprised 15 subjects each; moderate and severe based on clinical, radiological, and laboratory findings. Ten age and sex matched apparently healthy individuals were included in this study as a control group. About 1 ml EDTA anti-coagulated blood samples were collected for measuring expression of NKG2A/CD159a on CD56+ CD3- NK and CD3+CD8+ T cells by flow cytometry. Results revealed that COVID-19 patients had significantly lower NK and CD8+ T cell counts compared to healthy subjects. Severe cases had significantly lower CD8+ T counts compared to moderate ones. Percentages of NK and CD8+T cells expressing NKG2A receptor were significantly higher in cases compared to controls. Comparison between severe and moderate cases revealed that although the percentages of NK cells expressing NKG2A receptor were not significantly higher in severe cases, the mean fluorescence intensity was significantly higher. The percentages of CD8 +T cells expressing NKG2A receptor were significantly higher in severe cases with higher mean fluorescence intensity. In conclusion, our results indicate that elevated NKG2A expression on cytotoxic lymphocytes correlates with disease severity in COVID-19 patients, and may serve as a potential marker for prognosis. Additionally, the blockade of NKG2A should be investigated as means of enhancing NK cell and cytotoxic T cells antiviral immunity in patients with severe COVID-19 infection.


Assuntos
COVID-19 , Subfamília C de Receptores Semelhantes a Lectina de Células NK , Linfócitos T CD8-Positivos , Humanos , Células Matadoras Naturais , SARS-CoV-2
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