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1.
Clin Exp Rheumatol ; 38 Suppl 126(4): 222-227, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33095146

RESUMO

There is accumulating evidence that patients with primary Sjögren's syndrome (pSS) display aberrant CD4+ T cell responses, both in the peripheral compartment and in the inflamed salivary glands. CD4+ T cell abnormalities are also critically associated with B cell hyper activation, one of the hallmarks of disease, which is linked with disease severity and evolution to lymphoma. T cell activation and the cross-talk between T and B cells are tightly regulated by the balance between co-stimulatory pathways, such as the interactions between CD80/CD86:CD28, CD40:CD40L and ICOS:ICOSL, and co-inhibitory signals, including the immunoregulatory CTLA-4 protein. Evidence from patients with pSS as well as data from animal models of the disease suggests that these pathways play a critical role in pSS pathogenesis and their targeting could be exploited for therapeutic purposes. In this review, we first summarise the evidence implicating aberrant T cell co-stimulation and co-inhibition in driving the disease before focusing on the results of recent randomised controlled trials (RCTs) with compounds able to block T cell co-stimulation and enhance T cell co-inhibition. Despite a clear biological effect on downstream B cell activation has been observed in patients treated with CTLA-4-Ig (abatacept) and with monoclonal antibodies targeting CD40 and ICOSL, the clinical efficacy of this approach has so far yielded mixed results; while the anti-CD40 monoclonal antibody iscalimab showed significant improvement in systemic disease activity compared to placebo, two large RCTs with abatacept and a phase IIa RCT with an anti-ICOSL monoclonal antibody (prezalumab) failed to reach their primary endpoints. Although the discrepancies between biological and clinical efficacy of targeting T cell co-stimulation on pSS remain unresolved, several factors including drug bioavailability and receptor occupancy, patient stratification based on T-cell related biomarkers and the choice of study outcome are likely to play an important role and form the basis for further work towards the quest for a disease-modifying biologic therapy in pSS.


Assuntos
Síndrome de Sjogren , Animais , Humanos , Ativação Linfocitária , Glândulas Salivares , Síndrome de Sjogren/tratamento farmacológico , Linfócitos T , Resultado do Tratamento
2.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 36(8): 673-679, 2020 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-32958122

RESUMO

Objective To investigate the therapeutic effect and mechanism of paeoniflorin on dextran sulphate sodium (DSS)-induced ulcerative colitis (UC) mice. Methods C57BL/6 male mice were randomly divided into control group, model group, 600 mg/(kg.d) mesalazine treatment group, (12.5, 25, 50) mg/(kg.d) paeoniflorin treatment group, with 10 mice in each. All mice were treated with 30 g/L DSS for 5 days except the control group. Meanwhile, the mice in the other groups were orally administrated corresponding drugs for 10 days, while the mice in the control and model groups were given equivalent volumes of distilled water. Body mass, fecal characteristics and hematochezia of the mice were observed and recorded daily, and then disease activity index (DAI) was evaluated and calculated. Pathological changes in the colon were observed by HE staining. The levels of anti-flagellin antibody, interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α) in the serum were measured by ELISA. The expression levels of Toll-like receptor 5 (TLR5), myeloid differentiation factor 88 (MyD88) and nuclear factor kappa-Bp65 (NF-κBp65) in the colon tissues were evaluated by Western blot analysis and the activation of lymphocytes in mesenteric lymph node (MLN) was detected by flow cytometry. Results Compared with the control group, DAI scores in the model group were significantly raised, the colon length was significantly shortened, and the epithelium and intestinal gland disappeared. In addition, the serum levels of anti-flagellin antibody, IL-6, TNF-α and the protein levels of TLR5, MyD88, NF-κBp65 in the colon significantly increased, and the activation of T lymphocytes in MLN went up in the model group. All symptoms above were alleviated in the mesalazine and paeoniflorin groups compared with the model group. Conclusion Paeoniflorin can attenuate UC in mice by inhibiting the expression of flagellin and TLR5, and the activation of T cells.


Assuntos
Colite Ulcerativa , Glucosídeos , Ativação Linfocitária , Monoterpenos , Linfócitos T , Receptor 5 Toll-Like , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Anti-Inflamatórios não Esteroides/uso terapêutico , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Colo/efeitos dos fármacos , Sulfato de Dextrana/toxicidade , Glucosídeos/farmacologia , Glucosídeos/uso terapêutico , Ativação Linfocitária/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Monoterpenos/farmacologia , Monoterpenos/uso terapêutico , Distribuição Aleatória , Linfócitos T/efeitos dos fármacos , Receptor 5 Toll-Like/genética
3.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 36(8): 680-686, 2020 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-32958123

RESUMO

Objective To investigate the role of butyrophilin 3A1 (BTN3A1) in the activation and proliferation of human peripheral blood Vγ9Vδ2 T cells induced by M. tuberculosis heat resistant antigen (MTB-HAg). Methods Human peripheral blood mononuclear cells (PBMCs) were treated with BTN3A1 blocking antibody for 3 hours and then stimulated with MTB-HAg or phosphoantigen (PAg). At 24 hours of stimulation, the cells were collected to detect the expression of CD69 in Vγ9Vδ2 T cells by flow cytometry. At 20 hours of stimulation, the cells were collected to detect the proportions of cells producing helper T cell type I (Th1) cytokines IFN-γ and tumor necrosis factor α (TNF-α) in the Vγ9Vδ2 T cells. The PBMCs were also stimulated and cultured in IL-2-containing medium for 10 days, and the expansion and proliferation activity of Vγ9Vδ2 T cells were detected. Results After stimulated with MTB-HAg, the average fluorescence intensity of CD69 and the proportion of CD69 positive cells in Vγ9Vδ2 T cells decreased significantly in BTN3A1 blocked group, being 13.84% and 43.00% of those in the stimulated group, respectively. However, the average fluorescence intensity of CD69 molecules and the proportion of positive cells in PAg blocked group were significantly inhibited (3.10%, 4.47% and 9.53%, 10.91% of those in the stimulated group). The proportions of IFN-γ and TNF-α producing Vγ9Vδ2 T cells stimulated with MTB-HAg decreased significantly in the BTN3A1 blocked group, and the expansion number and cell proliferation activity of Vγ9Vδ2 T cells were also reduced significantly in the BTN3A1 blocked group. The results were similar to those of the PAg blocked group. Conclusion BTN3A1 promotes activation and proliferation of peripheral blood Vγ9Vδ2 T cells induced by MTB-HAg.


Assuntos
Antígenos de Bactérias , Antígenos CD , Butirofilinas , Ativação Linfocitária , Linfócitos T , Antígenos de Bactérias/imunologia , Antígenos CD/genética , Antígenos CD/metabolismo , Butirofilinas/genética , Butirofilinas/metabolismo , Proliferação de Células/genética , Humanos , Ativação Linfocitária/genética , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Linfócitos T/citologia , Linfócitos T/imunologia
4.
PLoS One ; 15(9): e0239516, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32956398

RESUMO

Intense dance training leads to inflammation, which may impair the health and performance of the practitioners. Herein, we evaluate the effect of a single street dancing class on the profile of muscle enzymes, lymphocyte activation, and cell surface CD62L expression. We also investigated the correlation between muscle enzymes, adhesion molecules, and lymphocyte activation in dancers. Fifteen male participants (mean ± standard error: age 22.4 ± 1.08 years, body mass index 24.8 ± 0.69 kg/m2, body fat 12.3 ± 1.52%), who were amateur dancers, had blood samples collected previously and subsequent to a high-intensity street dance class. After the class, dancers showed an increase in total lymphocyte count (2.0-fold), creatine kinase (CK)-NAC (4.87%), and CK-MB (3.36%). We also observed a decrease (2.5-fold) in reactive oxygen species (ROS) produced by lymphocytes, under phorbol myristate acetate-stimulated environments. Following the dance class, CD62L expression in lymphocytes decreased (51.42%), while there was a negative correlation between the intensity of the exercise and CD62L expression (r = -0.73; p = 0.01). Lymphocytes were less responsive to stimuli after a single bout of street dancing, indicating transient immunosuppression.


Assuntos
Dança/fisiologia , Selectina L/análise , Ativação Linfocitária , Creatina Quinase Forma MB/sangue , Dança/educação , Frequência Cardíaca , Humanos , Inflamação , Ativação Linfocitária/efeitos dos fármacos , Contagem de Linfócitos , Masculino , Espécies Reativas de Oxigênio/sangue , Acetato de Tetradecanoilforbol/farmacologia , Adulto Jovem
5.
Nucleic Acids Res ; 48(18): 10164-10183, 2020 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-32990751

RESUMO

T cells are central to the immune response against various pathogens and cancer cells. Complex networks of transcriptional and post-transcriptional regulators, including microRNAs (miRNAs), coordinate the T cell activation process. Available miRNA datasets, however, do not sufficiently dissolve the dynamic changes of miRNA controlled networks upon T cell activation. Here, we established a quantitative and time-resolved expression pattern for the entire miRNome over a period of 24 h upon human T-cell activation. Based on our time-resolved datasets, we identified central miRNAs and specified common miRNA expression profiles. We found the most prominent quantitative expression changes for miR-155-5p with a range from initially 40 molecules/cell to 1600 molecules/cell upon T-cell activation. We established a comprehensive dynamic regulatory network of both the up- and downstream regulation of miR-155. Upstream, we highlight IRF4 and its complexes with SPI1 and BATF as central for the transcriptional regulation of miR-155. Downstream of miR-155-5p, we verified 17 of its target genes by the time-resolved data recorded after T cell activation. Our data provide comprehensive insights into the range of stimulus induced miRNA abundance changes and lay the ground to identify efficient points of intervention for modifying the T cell response.


Assuntos
Linfócitos T CD4-Positivos/metabolismo , Ativação Linfocitária , MicroRNAs/metabolismo , Subpopulações de Linfócitos T/metabolismo , Adulto , Linfócitos T CD4-Positivos/citologia , Feminino , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Humanos , Subpopulações de Linfócitos T/citologia , Adulto Jovem
6.
PLoS One ; 15(9): e0238575, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32941476

RESUMO

OBJECTIVE: Optimization of antiretroviral therapy and anti-inflammatory treatments, such as statins, are among the strategies aimed at reducing metabolic disorders, inflammation and immune activation in people living with HIV (PLWH). We evaluated the potential benefit of combining both strategies. DESIGN: Forty-two PLWH aged ≥40 years receiving a protease inhibitor (PI)-based regimen were randomized (1:1) to switch from PI to Raltegravir (n = 20), or to remain on PI (n = 22). After 24 weeks, all patients received atorvastatin 20mg/day for 48 weeks. METHODS: We analyzed plasma inflammatory as well as T-cell maturation, activation, exhaustion and senescence markers at baseline, 24 and 72 weeks. RESULTS: Plasma inflammatory markers remained unchanged. Furthermore, no major changes on T-cell maturation subsets, immunoactivation, exhaustion or immunosenescence markers in both CD4 and CD8 T cell compartments were observed. Only a modest decrease in the frequency of CD38+ CD8 T cells and an increase in the frequency of CD28-CD57+ in both CD4 and CD8 T-cell compartments were noticed in the Raltegravir-switched group. CONCLUSIONS: The study combined antiretroviral switch to Raltegravir and Statin-based anti-inflammatory strategies to reduce inflammation and chronic immune activation in PLWH. Although this combination was safe and well tolerated, it had minimal impact on inflammatory and immunological markers. CLINICAL TRIALS REGISTRATION: NCT02577042.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Anticolesterolemiantes/uso terapêutico , Atorvastatina/uso terapêutico , Infecções por HIV/tratamento farmacológico , Inibidores da Protease de HIV/uso terapêutico , Raltegravir Potássico/uso terapêutico , Adulto , Fármacos Anti-HIV/administração & dosagem , Anticolesterolemiantes/administração & dosagem , Atorvastatina/administração & dosagem , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Feminino , Infecções por HIV/sangue , Infecções por HIV/imunologia , Inibidores da Protease de HIV/administração & dosagem , Humanos , Imunossenescência/efeitos dos fármacos , Inflamação/sangue , Inflamação/tratamento farmacológico , Inflamação/imunologia , Ativação Linfocitária/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Raltegravir Potássico/administração & dosagem
7.
Medicine (Baltimore) ; 99(36): e21803, 2020 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-32899009

RESUMO

RATIONALE: Complex immune dysregulation in interferon (IFN) and T cell response has been observed in human immunodeficiency virus (HIV-1)-infected patients as well as in coronavirus disease-2019 (COVID-19) patients. However, severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2)/HIV-1 coinfection has been described in only few cases worldwide and no data are available on immunological outcomes in HIV-1-patients infected with SARS-CoV-2. Hence, this study aims to compare type I IFN response and T cell activation levels between a SARS-CoV-2/HIV-1-coinfected female patient and age-matched HIV-1-positive or uninfected women. PATIENT CONCERNS: A 52-year-old woman diagnosed with SARS-CoV-2/HIV-1 coinfection, ten HIV-1-positive women and five age-matched-healthy individuals were enrolled in this study. DIAGNOSES: SARS-CoV-2 infection caused severe pneumonia in the second week of illness in HIV-1-positive patient under protease inhibitors. Chest high-resolution computed tomography images of the SARS-CoV-2/HIV-1-coinfected patient showed bilateral ground-glass opacities. INTERVENTIONS: SARS-CoV-2/HIV-1-coinfected female patient under darunavir/cobicistat regimen received a 7-days hydroxychloroquine therapy. Analysis of IFNα/ß mRNA levels and CD4 and CD8 T cell (CD38, human leukocyte antigen-DR [HLA-DR], CD38 HLA-DR) frequencies were performed by RT/real-time PCR assays and flow cytometry, respectively. Median relative difference (MRD) was calculated for each immunological variable. For values greater than reference, MRD should be a positive number and for values that are smaller, MRD should be negative. OUTCOMES: The severe pneumonia observed in SARS-CoV-2/HIV-1-positive patient under protease inhibitors was reversed by a 7-days hydroxychloroquine therapy. At the end of treatment, on day 7, patient reported resolution of fever, normalization of respiratory rate (14 breaths/min), and improved oxygen arterial pressure with a FiO2 of 30%. MRD values for IFNα/ß and CD4 and CD8 T cells expressing CD38 and/or HLA-DR found in SARS-CoV-2-/HIV-1-coinfected woman were approximatively equal to 0 when refereed respectively to HIV-1-positive female patients [MRDs IFNα/ß: median -0.2545 (range: -0.5/0.1); T cells: median -0.11 (range: -0.8/1.3)] and ≥ 6 when referred to healthy individuals [MRDs IFNα/ß: median 28.45 (range: 15/41.9); T cells: median 10 (range 6/22)]. LESSONS: These results indicate that SARS-CoV-2 infection in HIV-1-positive female patient was associated with increased levels of IFNα/ß-mRNAs and T cell activation compared to healthy individuals.


Assuntos
Infecções por Coronavirus/complicações , Infecções por HIV/complicações , Pneumonia Viral/complicações , Síndrome Respiratória Aguda Grave/complicações , Antirretrovirais/uso terapêutico , Betacoronavirus , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Estudos de Casos e Controles , Infecções por Coronavirus/tratamento farmacológico , Inibidores Enzimáticos/uso terapêutico , Feminino , Infecções por HIV/tratamento farmacológico , Humanos , Hidroxicloroquina/uso terapêutico , Interferons/sangue , Ativação Linfocitária , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/tratamento farmacológico , RNA Mensageiro , Reação em Cadeia da Polimerase em Tempo Real , Síndrome Respiratória Aguda Grave/tratamento farmacológico , Síndrome Respiratória Aguda Grave/virologia
8.
PLoS One ; 15(9): e0239668, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32970762

RESUMO

We developed an approach for substantial attenuation of Mycobacterium tuberculosis by prolonged culturing under gradually acidifying conditions. Bacteria subjected to acidification lost the capacity to form colonies on solid media, but readily resuscitated their growth in the murine host, providing a useful model to study in vivo development of infection mimicking latent and reactivation tuberculosis (TB) in humans. Here we characterize biomarkers of lung pathology and immune responses triggered by such attenuated bacteria in genetically TB-susceptible and resistant mice. In susceptible I/St mice, CFU counts in lungs and spleens were ~1.5-log higher than in resistant B6 mice, accompanied by diffuse pneumonia and excessive lung infiltration with highly activated CD44+CD62L- T-lymphocytes resulting in death between months 7-9 post challenge. B6 mice were characterized by development of local inflammatory foci, higher production of pro-inflammatory IL-6 and IL-11 cytokines and a more balanced T-cell activation in their lungs. CFU counts remained stable in B6 mice during the whole 18-mo observation period, and all mice survived. Thus, we established a mouse model of fatal reactivation TB vs. indefinite mycobacterial possession after identical challenge and characterized the features of immune responses in the lung tissue underlining these polar phenotypes.


Assuntos
Predisposição Genética para Doença , Interleucinas/metabolismo , Pulmão/imunologia , Ativação Linfocitária , Tuberculose Pulmonar/imunologia , Tuberculose Esplênica/imunologia , Animais , Carga Bacteriana , Células Cultivadas , Feminino , Receptores de Hialuronatos/genética , Receptores de Hialuronatos/metabolismo , Interleucinas/genética , Selectina L/genética , Selectina L/metabolismo , Pulmão/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , Mycobacterium tuberculosis/patogenicidade , Baço/imunologia , Baço/microbiologia , Linfócitos T/imunologia , Tuberculose Pulmonar/genética , Tuberculose Esplênica/genética
9.
Int J Mol Med ; 46(4): 1266-1273, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32945352

RESUMO

The outbreak of the 2019 coronavirus disease (named, COVID­19), caused by the novel SARS­CoV­2 virus, represents a worldwide severe threat to public health. It is of the utmost importance to characterize the immune responses against the SARS­CoV­2 and the mechanisms of hyperinflammation, in order to design better therapeutic strategies for COVID­19. In the present study, a transcriptomic analysis was performed to profile the immune signatures in lung and the bronchoalveolar lavage fluid samples from COVID­19 patients and controls. Our data concordantly revealed increased humoral responses to infection. The elucidation of the host responses to SARS­CoV­2 infection may further improve our understanding of COVID­19 pathogenesis and suggest better therapeutic strategies.


Assuntos
Linfócitos B/imunologia , Betacoronavirus/imunologia , Infecções por Coronavirus/imunologia , Ativação Linfocitária , Pneumonia Viral/imunologia , Transcriptoma , Linfócitos B/metabolismo , Betacoronavirus/fisiologia , Líquido da Lavagem Broncoalveolar , Infecções por Coronavirus/genética , Bases de Dados Factuais , Feminino , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Interações Hospedeiro-Patógeno , Humanos , Pulmão/imunologia , Pulmão/metabolismo , Masculino , Pandemias , Pneumonia Viral/genética
10.
Nat Commun ; 11(1): 4786, 2020 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-32963227

RESUMO

Evidence points to an indispensable function of macrophages in tissue regeneration, yet the underlying molecular mechanisms remain elusive. Here we demonstrate a protective function for the IL-33-ST2 axis in bronchial epithelial repair, and implicate ST2 in myeloid cell differentiation. ST2 deficiency in mice leads to reduced lung myeloid cell infiltration, abnormal alternatively activated macrophage (AAM) function, and impaired epithelial repair post naphthalene-induced injury. Reconstitution of wild type (WT) AAMs to ST2-deficient mice completely restores bronchial re-epithelialization. Central to this mechanism is the direct effect of IL-33-ST2 signaling on monocyte/macrophage differentiation, self-renewal and repairing ability, as evidenced by the downregulation of key pathways regulating myeloid cell cycle, maturation and regenerative function of the epithelial niche in ST2-/- mice. Thus, the IL-33-ST2 axis controls epithelial niche regeneration by activating a large multi-cellular circuit, including monocyte differentiation into competent repairing AAMs, as well as group-2 innate lymphoid cell (ILC2)-mediated AAM activation.


Assuntos
Bronquíolos/metabolismo , Diferenciação Celular/efeitos dos fármacos , Células Epiteliais/metabolismo , Proteína 1 Semelhante a Receptor de Interleucina-1/metabolismo , Interleucina-33/metabolismo , Interleucina-33/farmacologia , Animais , Bronquíolos/lesões , Bronquíolos/patologia , Citocinas/metabolismo , Modelos Animais de Doenças , Células Epiteliais/patologia , Feminino , Proteína 1 Semelhante a Receptor de Interleucina-1/genética , Pulmão/patologia , Ativação Linfocitária , Linfócitos/metabolismo , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Transdução de Sinais
11.
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
12.
Sci Immunol ; 5(51)2020 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-32989174

RESUMO

Severe COVID-19 is characterized by excessive inflammation of the lower airways. The balance of protective versus pathological immune responses in COVID-19 is incompletely understood. Mucosa-associated invariant T (MAIT) cells are antimicrobial T cells that recognize bacterial metabolites, and can also function as innate-like sensors and mediators of antiviral responses. Here, we investigated the MAIT cell compartment in COVID-19 patients with moderate and severe disease, as well as in convalescence. We show profound and preferential decline in MAIT cells in the circulation of patients with active disease paired with strong activation. Furthermore, transcriptomic analyses indicated significant MAIT cell enrichment and pro-inflammatory IL-17A bias in the airways. Unsupervised analysis identified MAIT cell CD69high and CXCR3low immunotypes associated with poor clinical outcome. MAIT cell levels normalized in the convalescent phase, consistent with dynamic recruitment to the tissues and later release back into the circulation when disease is resolved. These findings indicate that MAIT cells are engaged in the immune response against SARS-CoV-2 and suggest their possible involvement in COVID-19 immunopathogenesis.


Assuntos
Betacoronavirus/imunologia , Infecções por Coronavirus/patologia , Células T Invariáveis Associadas à Mucosa/imunologia , Pneumonia Viral/patologia , Adulto , Idoso , Antígenos CD/metabolismo , Antígenos de Diferenciação de Linfócitos T/metabolismo , Infecções por Coronavirus/imunologia , Feminino , Humanos , Imunidade Inata/imunologia , Inflamação/imunologia , Interleucina-17/metabolismo , Lectinas Tipo C/metabolismo , Ativação Linfocitária/imunologia , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/imunologia , Receptores CXCR3/metabolismo , Adulto Jovem
14.
Nat Commun ; 11(1): 4367, 2020 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-32868763

RESUMO

Invariant natural killer T (iNKT), mucosal-associated invariant T (MAIT), and γδ T cells are innate T cells that acquire memory phenotype in the thymus and share similar biological characteristics. However, how their effector differentiation is developmentally regulated is still unclear. Here, we identify analogous effector subsets of these three innate T cell types in the thymus that share transcriptional profiles. Using single-cell RNA sequencing, we show that iNKT, MAIT and γδ T cells mature via shared, branched differentiation rather than linear maturation or TCR-mediated instruction. Simultaneous TCR clonotyping analysis reveals that thymic maturation of all three types is accompanied by clonal selection and expansion. Analyses of mice deficient of TBET, GATA3 or RORγt and additional in vivo experiments corroborate the predicted differentiation paths, while human innate T cells from liver samples display similar features. Collectively, our data indicate that innate T cells share effector differentiation processes in the thymus.


Assuntos
Diferenciação Celular , Imunidade Inata , Linfócitos T/metabolismo , Timo/imunologia , Animais , Células Cultivadas , Seleção Clonal Mediada por Antígeno , Humanos , Fígado/citologia , Fígado/imunologia , Ativação Linfocitária , Camundongos , Células T Invariáveis Associadas à Mucosa/metabolismo , Células T Matadoras Naturais/metabolismo , Análise de Sequência de RNA , Análise de Célula Única , Células Th17/metabolismo , Timo/citologia
15.
J Immunol ; 205(9): 2437-2446, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32878912

RESUMO

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), emerged in late 2019 and has since become a global pandemic. Pathogen-specific Abs are typically a major predictor of protective immunity, yet human B cell and Ab responses during COVID-19 are not fully understood. In this study, we analyzed Ab-secreting cell and Ab responses in 20 hospitalized COVID-19 patients. The patients exhibited typical symptoms of COVID-19 and presented with reduced lymphocyte numbers and increased T cell and B cell activation. Importantly, we detected an expansion of SARS-CoV-2 nucleocapsid protein-specific Ab-secreting cells in all 20 COVID-19 patients using a multicolor FluoroSpot Assay. Out of the 20 patients, 16 had developed SARS-CoV-2-neutralizing Abs by the time of inclusion in the study. SARS-CoV-2-specific IgA, IgG, and IgM Ab levels positively correlated with SARS-CoV-2-neutralizing Ab titers, suggesting that SARS-CoV-2-specific Ab levels may reflect the titers of neutralizing Abs in COVID-19 patients during the acute phase of infection. Last, we showed that IL-6 and C-reactive protein serum concentrations were higher in patients who were hospitalized for longer, supporting the recent observations that IL-6 and C-reactive protein could be used as markers for COVID-19 severity. Altogether, this study constitutes a detailed description of clinical and immunological parameters in 20 COVID-19 patients, with a focus on B cell and Ab responses, and describes tools to study immune responses to SARS-CoV-2 infection and vaccination.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Linfócitos B/imunologia , Betacoronavirus/imunologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/imunologia , Hospitalização , Pneumonia Viral/epidemiologia , Pneumonia Viral/imunologia , Adulto , Idoso , Biomarcadores/sangue , Proteína C-Reativa/análise , Estudos de Coortes , Infecções por Coronavirus/virologia , Feminino , Humanos , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Interleucina-6/sangue , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Proteínas do Nucleocapsídeo/imunologia , Pandemias , Pneumonia Viral/virologia , Suécia/epidemiologia
16.
Clin Immunol ; 220: 108591, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32920210

RESUMO

Most severe cases with COVID-19, especially those with pulmonary failure, are not a consequence of viral burden and/or failure of the 'adaptive' immune response to subdue the pathogen by utilizing an adequate 'adaptive' immune defense. Rather it is a consequence of immunopathology, resulting from imbalanced innate immune response, which may not be linked to pathogen burden at all. In fact, it might be described as an autoinflammatory disease. The Kawasaki-like disease seen in children with SARS-CoV-2 exposure might be another example of similar mechanism.


Assuntos
Autoimunidade/genética , Betacoronavirus/patogenicidade , Infecções por Coronavirus/imunologia , Síndrome da Liberação de Citocina/imunologia , Interações Hospedeiro-Patógeno/imunologia , Pneumonia Viral/imunologia , Insuficiência Respiratória/imunologia , Doença Aguda , Imunidade Adaptativa , Betacoronavirus/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD4-Positivos/virologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/patologia , Linfócitos T CD8-Positivos/virologia , Infecções por Coronavirus/genética , Infecções por Coronavirus/fisiopatologia , Síndrome da Liberação de Citocina/genética , Síndrome da Liberação de Citocina/fisiopatologia , Interações Hospedeiro-Patógeno/genética , Humanos , Imunidade Inata , Ativação Linfocitária , Síndrome de Linfonodos Mucocutâneos/genética , Síndrome de Linfonodos Mucocutâneos/imunologia , Síndrome de Linfonodos Mucocutâneos/fisiopatologia , Pandemias , Pneumonia Viral/genética , Pneumonia Viral/fisiopatologia , Insuficiência Respiratória/genética , Insuficiência Respiratória/fisiopatologia , Índice de Gravidade de Doença
17.
Med Microbiol Immunol ; 209(6): 681-691, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32918599

RESUMO

Chimeric Antigen Receptor (CAR)-redirected T cells show great efficacy in the patient-specific therapy of hematologic malignancies. Here, we demonstrate that a DARPin with specificity for CD4 specifically redirects and triggers the activation of CAR engineered T cells resulting in the depletion of CD4+ target cells aiming for elimination of the human immunodeficiency virus (HIV) reservoir.


Assuntos
Repetição de Anquirina , Linfócitos T CD4-Positivos/virologia , Infecções por HIV/imunologia , HIV/isolamento & purificação , Imunoterapia Adotiva , Depleção Linfocítica/métodos , Peptídeos/farmacologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Relação Dose-Resposta Imunológica , Avaliação Pré-Clínica de Medicamentos , Gammaretrovirus/genética , Vetores Genéticos/genética , Células HEK293 , Infecções por HIV/virologia , Humanos , Ativação Linfocitária , Peptídeos/química , Anticorpos de Cadeia Única/imunologia , Transdução Genética
18.
Proc Natl Acad Sci U S A ; 117(37): 22944-22952, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32868441

RESUMO

γδ T cells form an abundant part of the human cellular immune system, where they respond to tissue damage, infection, and cancer. The spectrum of known molecular targets recognized by Vδ1-expressing γδ T cells is becoming increasingly diverse. Here we describe human γδ T cells that recognize CD1b, a lipid antigen-presenting molecule, which is inducibly expressed on monocytes and dendritic cells. Using CD1b tetramers to study multiple donors, we found that many CD1b-specific γδ T cells use Vδ1. Despite their common use of Vδ1, three CD1b-specific γδ T cell receptors (TCRs) showed clear differences in the surface of CD1b recognized, the requirement for lipid antigens, and corecognition of butryophilin-like proteins. Several Vγ segments were present among the CD1b-specific TCRs, but chain swap experiments demonstrated that CD1b specificity was mediated by the Vδ1 chain. One of the CD1b-specific Vδ1+ TCRs paired with Vγ4 and shows dual reactivity to CD1b and butyrophilin-like proteins. αß TCRs typically recognize the peptide display platform of MHC proteins. In contrast, our results demonstrate the use of rearranged receptors to mediate diverse modes of recognition across the surface of CD1b in ways that do and do not require carried lipids.


Assuntos
Antígenos CD1/metabolismo , Linfócitos Intraepiteliais/imunologia , Linfócitos Intraepiteliais/metabolismo , Apresentação do Antígeno , Antígenos CD1/imunologia , Cristalografia por Raios X/métodos , Humanos , Linfócitos Intraepiteliais/fisiologia , Lipídeos/imunologia , Ativação Linfocitária/imunologia , Modelos Moleculares , Monócitos/metabolismo , Linfócitos T/imunologia
19.
PLoS One ; 15(9): e0222548, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32870913

RESUMO

The paracaspase mucosa-associated lymphoid tissue lymphoma translocation protein-1 (MALT1) regulates nuclear-factor-kappa-B (NF-κB) activation downstream of surface receptors with immunoreceptor tyrosine-based activation motifs (ITAMs), such as the B-cell or T-cell receptor and has thus emerged as a therapeutic target for autoimmune diseases. However, recent reports demonstrate the development of lethal autoimmune inflammation due to the excessive production of interferon gamma (IFN-É£) and defective differentiation of regulatory T-cells in genetically modified mice deficient in MALT1 paracaspase activity. To address this issue, we explored the effects of pharmacological MALT1 inhibition on the balance between T-effector and regulatory T-cells. Here we demonstrate that allosteric inhibition of MALT1 suppressed Th1, Th17 and Th1/Th17 effector responses, and inhibited T-cell dependent B-cell proliferation and antibody production. Allosteric MALT1 inhibition did not interfere with the suppressive function of human T-regulatory cells, although it impaired de novo differentiation of regulatory T-cells from naïve T-cells. Treatment with an allosteric MALT1 inhibitor alleviated the cytokine storm, including IFN-É£, in a mouse model of acute T-cell activation, and long-term treatment did not lead to an increase in IFN-É£ producing CD4 cells or tissue inflammation. Together, our data demonstrate that the effects of allosteric inhibition of MALT1 differ from those seen in mice with proteolytically inactive MALT1, and thus we believe that MALT1 is a viable target for B and T-cell driven autoimmune diseases.


Assuntos
Linfócitos B/efeitos dos fármacos , Células Dendríticas/efeitos dos fármacos , Proteína de Translocação 1 do Linfoma de Tecido Linfoide Associado à Mucosa/antagonistas & inibidores , Inibidores de Proteases/farmacologia , Linfócitos T Citotóxicos/efeitos dos fármacos , Regulação Alostérica/efeitos dos fármacos , Animais , Linfócitos B/imunologia , Linfócitos B/metabolismo , Células Cultivadas , Células Dendríticas/imunologia , Feminino , Transferência Ressonante de Energia de Fluorescência , Voluntários Saudáveis , Humanos , Injeções Intraperitoneais , Interferon gama/imunologia , Interferon gama/metabolismo , Ativação Linfocitária/efeitos dos fármacos , Camundongos , Camundongos Knockout , Proteína de Translocação 1 do Linfoma de Tecido Linfoide Associado à Mucosa/genética , Proteína de Translocação 1 do Linfoma de Tecido Linfoide Associado à Mucosa/imunologia , Proteína de Translocação 1 do Linfoma de Tecido Linfoide Associado à Mucosa/metabolismo , Fenotiazinas/farmacologia , Cultura Primária de Células , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/metabolismo , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Células Th1/efeitos dos fármacos , Células Th1/imunologia , Células Th1/metabolismo
20.
Viruses ; 12(9)2020 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-32967229

RESUMO

As evidence has mounted that virus-infected cells, such as cancer cells, negatively regulate the function of T-cells via immune checkpoints, it has become increasingly clear that viral infections similarly exploit immune checkpoints as an immune system escape mechanism. Although immune checkpoint therapy has been successfully used in cancer treatment, numerous studies have suggested that such therapy may also be highly relevant for treating viral infection, especially chronic viral infections. However, it has not yet been applied in this manner. Here, we reviewed recent findings regarding immune checkpoints in viral infections, including COVID-19, and discussed the role of immune checkpoints in different viral infections, as well as the potential for applying immune checkpoint blockades as antiviral therapy.


Assuntos
Fatores Imunológicos/imunologia , Viroses/imunologia , Vírus/imunologia , Animais , Antivirais/uso terapêutico , Doença Crônica , Humanos , Fatores Imunológicos/antagonistas & inibidores , Imunoterapia , Ativação Linfocitária/efeitos dos fármacos , Linfócitos T/imunologia , Linfócitos T/patologia , Viroses/terapia , Vírus/classificação
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