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1.
Eur J Immunol ; 51(9): 2178-2187, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34180545

RESUMO

T cells are central players of the adaptive immune system by protecting us from recurring infections and by killing malignant cells. Protective T cell responses rely on the concerted production of effector molecules such as cytolytic mediators, granzymes, and perforins, as well as pro-inflammatory cytokines and chemokines. Once activated, T cells drastically change their gene expression and rapidly respond to insults by producing ample amounts of effector molecules. In the absence of antigen, T cells remain in a quiescent state and survey our body for possible pathogenic insults. Resting T cells are, however, not inert, but continuously regulate their protein production to survive and to be prepared for possible re-infections. Here, we review our current knowledge on the regulation of gene expression in activated and quiescent T cells. We specifically focus on post-transcriptional mechanisms that define the protein output and that allow dormant cells to undergo active signaling and selective translation, keeping them poised for activation. Finally, we discuss which signals drive T cell survival and their preparedness to respond to insults and which mechanisms are involved in these processes.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Regulação da Expressão Gênica/imunologia , Ativação Linfocitária/imunologia , Transcriptoma/imunologia , Imunidade Adaptativa/imunologia , Citocinas/imunologia , Regulação da Expressão Gênica/genética , Granzimas/metabolismo , Humanos , Perforina/imunologia , Processamento Pós-Transcricional do RNA/genética , Transdução de Sinais/imunologia , Transcriptoma/genética
2.
Front Immunol ; 12: 643746, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34093532

RESUMO

Malaria remains one of the most serious health problems in developing countries. The causative agent of malaria, Plasmodium spp., have a complex life cycle involving multiple developmental stages as well as different morphological, biochemical and metabolic requirements. We recently found that γδ T cells control parasite growth using pore-forming proteins to deliver their cytotoxic proteases, the granzymes, into blood residing parasites. Here, we follow up on the molecular mechanisms of parasite growth inhibition by human pore-forming proteins. We confirm that Plasmodium falciparum infection efficiently depletes the red blood cells of cholesterol, which renders the parasite surrounding membranes susceptible to lysis by prokaryotic membrane disrupting proteins, such as lymphocytic granulysin or the human cathelicidin LL-37. Interestingly, not the cholesterol depletion but rather the simultaneous exposure of phosphatidylserine, a negatively charged phospholipid, triggers resistance of late stage parasitized red blood cells towards the eukaryotic pore forming protein perforin. Overall, by revealing the molecular events we establish here a pathogen-host interaction that involves host cell membrane remodeling that defines the susceptibility towards cytolytic molecules.


Assuntos
Membrana Eritrocítica/imunologia , Hemólise/imunologia , Malária Falciparum/imunologia , Perforina/imunologia , Plasmodium falciparum/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Linfócitos T/imunologia , Antígenos de Diferenciação de Linfócitos T , Peptídeos Catiônicos Antimicrobianos/imunologia , Suscetibilidade a Doenças , Membrana Eritrocítica/parasitologia , Humanos
3.
Front Immunol ; 12: 578548, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33815355

RESUMO

Objectives: To explore the potential role of CD3+CD8+CD161high TCRVα7.2+ mucosal-associated invariant T (MAIT) cells in the pathogenesis of primary biliary cholangitis (PBC). Methods: We enrolled 55 patients with PBC, 69 healthy controls (HCs), and 8 patients with hepatic hemangioma. Circulating MAIT cells and their chemokine receptor profiles and cytokine production were quantified using flow cytometry. Liver-resident MAIT cells were examined by immunofluorescence staining. CXCL12-mediated chemotaxis of MAIT cells was measured using a transwell migration assay. Plasma interleukin (IL)-18 was measured using ELISA, and cytokine production in IL-18-stimulated MAIT cells was detected using flow cytometry. Result: Peripheral MAIT cells were found to be significantly lower in patients with PBC (3.0 ± 3.2% vs. 9.4 ± 8.0%, p < 0.01) and negatively correlated with alkaline phosphatase (ALP) levels (r = -0.3209, p < 0.05). Liver immunofluorescence staining suggested that MAIT cells might accumulate in PBC liver. MAIT cells from patients with PBC expressed higher levels of CXCR4 (84.8 ± 18.0% vs. 58.7 ± 11.4%, p < 0.01), and the expression of CXCL12 was higher in PBC liver. CXCL12 promoted MAIT cell chemotaxis (70.4 ± 6.8% vs. 52.2 ± 3.5%, p < 0.01), which was attenuated by CXCR4 antagonist. MAIT cells from PBC produced significantly more interferon-γ (IFN-γ) (88.3 ± 4.2% vs. 64.2 ± 10.1%, p < 0.01), tumor necrosis factor-α (TNF-α) (93.0 ± 1.1% vs. 80.1 ± 5.3%, p < 0.01), Granzyme B (89.3 ± 3.3% vs. 72.1 ± 7.0%, p < 0.01), and perforin (46.8 ± 6.6% vs. 34.8 ± 7.7%, p < 0.05). MAIT cells from PBC expressed higher levels of IL18-Rα (83.8 ± 10.2% vs. 58.3 ± 8.7%, p < 0.01). Plasma IL-18 was more abundant in patients with PBC (286.8 ± 75.7 pg/ml vs. 132.9 ± 78.1 pg/ml, p < 0.01). IL-18 promoted IFN-γ production in MAIT cells (74.9 ± 6.6% vs. 54.7 ± 6.7%, p < 0.01), which was partially attenuated by blocking IL-18R (68.6 ± 8.3% vs. 43.5 ± 4.2%, p < 0.01). Conclusion: Mucosal-associated invariant T cells from patients with PBC accumulated in the liver via CXCL12-CXCR4-mediated chemotaxis, produced pro-inflammatory cytokines, and contributed to portal inflammation, which was potentially mediated by elevated IL-18. Targeting MAIT cells might be a therapeutic approach for PBC.


Assuntos
Quimiocina CXCL12/imunologia , Cirrose Hepática Biliar/imunologia , Fígado/imunologia , Células T Invariantes Associadas à Mucosa/imunologia , Receptores CXCR4/imunologia , Adulto , Fosfatase Alcalina/imunologia , Fosfatase Alcalina/metabolismo , Quimiocina CXCL12/metabolismo , Quimiotaxia/imunologia , Feminino , Granzimas/imunologia , Granzimas/metabolismo , Humanos , Interferon gama/imunologia , Interferon gama/metabolismo , Interleucina-18/imunologia , Interleucina-18/metabolismo , Fígado/metabolismo , Cirrose Hepática Biliar/sangue , Cirrose Hepática Biliar/metabolismo , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Células T Invariantes Associadas à Mucosa/metabolismo , Perforina/imunologia , Perforina/metabolismo , Receptores CXCR4/metabolismo , Fator de Necrose Tumoral alfa/imunologia , Fator de Necrose Tumoral alfa/metabolismo
4.
Clin Exp Immunol ; 205(1): 53-62, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33735518

RESUMO

High expression of the inhibitory receptor programmed cell death ligand 1 (PD-L1) on tumor cells and tumor stromal cells have been found to play a key role in tumor immune evasion in several human malignancies. However, the expression of PD-L1 on bone marrow mesenchymal stem cells (BMSCs) and whether the programmed cell death 1 (PD-1)/PD-L1 signal pathway is involved in the BMSCs versus T cell immune response in multiple myeloma (MM) remains poorly defined. In this study, we explored the expression of PD-L1 on BMSCs from newly diagnosed MM (NDMM) patients and the role of PD-1/PD-L1 pathway in BMSC-mediated regulation of CD8+ T cells. The data showed that the expression of PD-L1 on BMSCs in NDMM patients was significantly increased compared to that in normal controls (NC) (18·81 ± 1·61 versus 2·78± 0·70%; P < 0·001). Furthermore, the PD-1 expression on CD8+ T cells with NDMM patients was significantly higher than that in normal controls (43·22 ± 2·98 versus 20·71 ± 1·08%; P < 0·001). However, there was no significant difference in PD-1 expression of CD4+ T cells and natural killer (NK) cells between the NDMM and NC groups. Additionally, the co-culture assays revealed that BMSCs significantly suppressed CD8+ T cell function. However, the PD-L1 inhibitor effectively reversed BMSC-mediated suppression in CD8+ T cells. We also found that the combination of PD-L1 inhibitor and pomalidomide can further enhance the killing effect of CD8+ T cells on MM cells. In summary, our findings demonstrated that BMSCs in patients with MM may induce apoptosis of CD8+ T cells through the PD-1/PD-L1 axis and inhibit the release of perforin and granzyme B from CD8+ T cells to promote the immune escape of MM.


Assuntos
Antígeno B7-H1/imunologia , Medula Óssea/imunologia , Linfócitos T CD8-Positivos/imunologia , Imunidade/imunologia , Células-Tronco Mesenquimais/imunologia , Mieloma Múltiplo/imunologia , Receptor de Morte Celular Programada 1/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Linfócitos T CD4-Positivos/imunologia , Feminino , Granzimas/imunologia , Humanos , Células Matadoras Naturais/imunologia , Masculino , Pessoa de Meia-Idade , Perforina/imunologia , Transdução de Sinais/imunologia , Talidomida/análogos & derivados , Talidomida/imunologia , Evasão Tumoral/imunologia
5.
Cancer Immunol Immunother ; 70(11): 3137-3154, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33779796

RESUMO

BACKGROUND: Skin melanoma is a highly immunogenic cancer. The intratumoral immune cytolytic activity (CYT) reflects the ability of cytotoxic T and NK cells to eliminate cancer cells, and is associated with improved patient survival. Despite the enthusiastic clinical results seen in advanced-stage metastatic melanoma patients treated with immune checkpoint inhibitors, a subgroup of them will later relapse and develop acquired resistance. We questioned whether CYT associates with different genomic profiles and thus, patient outcome, in skin melanoma. METHODS: We explored the TCGA-SKCM dataset and stratified patients to distinct subgroups of cytolytic activity. The tumor immune contexture, somatic mutations and recurrent copy number aberrations were calculated using quanTIseq, MutSigCV and GISTIC2. Chromothriptic events were explored using CTLPScanner and cancer neoepitopes were predicted with antigen garnish. Each tumor's immunophenoscore was calculated using Immunophenogram. Mutational signatures and kataegis were explored using SigProfiler and compared to the known single or doublet base substitution signatures from COSMIC. RESULTS: Metastatic skin melanomas had significantly higher CYT levels compared to primary tumors. We assessed enrichment for immune-related gene sets within CYT-high tumors, whereas, CYT-low tumors were enriched for non-immune related gene sets. In addition, distinct mutational and neoantigen loads, primarily composed of C > T transitions, along with specific types of copy number aberrations, characterized each cytolytic subgroup. We found a broader pattern of chromothripsis across CYT-low tumors, where chromosomal regions harboring chromothriptic events, contained a higher number of cancer genes. SBS7a/b, SBS5 and SBS1 were the most prevalent mutational signatures across both cytolytic subgroups, but SBS1 differed significantly between them. SBS7a/b was mutually exclusive with SBS5 and SBS1 in both CYT subgroups. CYT-high patients had markedly higher immunophenoscore, suggesting that they should display a clinical benefit upon treatment with immune checkpoint inhibition therapy, compared to CYT-low patients. CONCLUSIONS: Overall, our data highlight the existence of distinct genomic features across cytolytic subgroups in skin melanoma, which might affect the patients' relapse rate or their acquisition of resistance to immune checkpoint inhibition therapies.


Assuntos
Citotoxicidade Imunológica/imunologia , Melanoma/genética , Melanoma/imunologia , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/imunologia , Granzimas/imunologia , Humanos , Células Matadoras Naturais/imunologia , Mutação , Perforina/imunologia , Linfócitos T Citotóxicos/imunologia
6.
Mol Cell ; 81(7): 1469-1483.e8, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33609448

RESUMO

We demonstrate that DNA hypomethylating agent (HMA) treatment can directly modulate the anti-tumor response and effector function of CD8+ T cells. In vivo HMA treatment promotes CD8+ T cell tumor infiltration and suppresses tumor growth via CD8+ T cell-dependent activity. Ex vivo, HMAs enhance primary human CD8+ T cell activation markers, effector cytokine production, and anti-tumor cytolytic activity. Epigenomic and transcriptomic profiling shows that HMAs vastly regulate T cell activation-related transcriptional networks, culminating with over-activation of NFATc1 short isoforms. Mechanistically, demethylation of an intragenic CpG island immediately downstream to the 3' UTR of the short isoform was associated with antisense transcription and alternative polyadenylation of NFATc1 short isoforms. High-dimensional single-cell mass cytometry analyses reveal a selective effect of HMAs on a subset of human CD8+ T cell subpopulations, increasing both the number and abundance of a granzyme Bhigh, perforinhigh effector subpopulation. Overall, our findings support the use of HMAs as a therapeutic strategy to boost anti-tumor immune response.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Ilhas de CpG/imunologia , Metilação de DNA/efeitos dos fármacos , Decitabina/farmacologia , Granzimas/imunologia , Ativação Linfocitária/efeitos dos fármacos , Metilação de DNA/imunologia , Humanos , Fatores de Transcrição NFATC/imunologia , Perforina/imunologia
7.
PLoS Negl Trop Dis ; 15(2): e0009059, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33539379

RESUMO

BACKGROUND: Signs of senescence and the late stages of differentiation associated with the more severe forms of Chagas disease have been described in the Trypanosoma cruzi antigen-specific CD4+ T-cell population. However, the mechanisms involved in these functions are not fully known. To date, little is known about the possible impact of benznidazole treatment on the T. cruzi-specific functional response of CD4+ T cells. METHODOLOGY/PRINCIPAL FINDINGS: The functional capacity of CD4+ T cells was analyzed by cytometric assays in chronic Chagas disease patients, with indeterminate form (IND) and cardiac alterations (CCC) (25 and 15, respectively) before and after benznidazole treatment. An increase in the multifunctional capacity (expression of IFN-γ, IL-2, TNF-α, perforin and/or granzyme B) of the antigen-specific CD4+ T cells was observed in indeterminate versus cardiac patients, which was associated with the reduced coexpression of inhibitory receptors (2B4, CD160, CTLA-4, PD-1 and/or TIM-3). The functional profile of these cells shows statistically significant differences between IND and CCC (p<0.001), with a higher proportion of CD4+ T cells coexpressing 2 and 3 molecules in IND (54.4% versus 23.1% and 4.1% versus 2.4%, respectively). A significant decrease in the frequencies of CD4+ T cells that coexpress 2, 3 and 4 inhibitory receptors was observed in IND after 24-48 months of treatment (p<0.05, p<0.01 and p<0.05, respectively), which was associated with an increase in antigen-specific multifunctional activity. The IND group showed, at 9-12 months after treatment, an increase in the CD4+ T cell subset coproducing three molecules, which were mainly granzyme B+, perforin+ and IFN-γ+ (1.4% versus 4.5%). CONCLUSIONS/SIGNIFICANCE: A CD4+ T cell dysfunctional process was detected in chronic Chagas disease patients, being more exacerbated in those patients with cardiac symptoms. After short-term benznidazole treatment (9-12 months), indeterminate patients showed a significant increase in the frequency of multifunctional antigen-specific CD4+ T cells.


Assuntos
Antiprotozoários/administração & dosagem , Linfócitos T CD4-Positivos/imunologia , Doença de Chagas/tratamento farmacológico , Nitroimidazóis/administração & dosagem , Trypanosoma cruzi/efeitos dos fármacos , Adulto , Anticorpos Antiprotozoários/imunologia , Doença de Chagas/imunologia , Doença de Chagas/parasitologia , Feminino , Granzimas/imunologia , Humanos , Interferon gama/imunologia , Masculino , Pessoa de Meia-Idade , Perforina/imunologia , Espanha , Trypanosoma cruzi/genética , Trypanosoma cruzi/imunologia , Adulto Jovem
8.
Front Immunol ; 11: 587581, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33262766

RESUMO

Inflammation is strictly interconnected to anti-inflammatory mechanisms to maintain tissue homeostasis. The disruption of immune homeostasis can lead to acute and chronic inflammatory diseases, as cardiovascular, pulmonary, metabolic diseases and cancer. The knowledge of the mechanisms involved in the development and progression of these pathological conditions is important to find effective therapies. Granzyme B (GrB) is a serine protease produced by a variety of immune, non-immune and tumor cells. Apoptotic intracellular and multiple extracellular functions of GrB have been recently identified. Its capability of cleaving extracellular matrix (ECM) components, cytokines, cell receptors and clotting proteins, revealed GrB as a potential multifunctional pro-inflammatory molecule with the capability of contributing to the pathogenesis of different inflammatory conditions, including inflammaging, acute and chronic inflammatory diseases and cancer. Here we give an overview of recent data concerning GrB activity on multiple targets, potentially allowing this enzyme to regulate a wide range of crucial biological processes that play a role in the development, progression and/or severity of inflammatory diseases. We focus our attention on the promotion by GrB of perforin-dependent and perforin-independent (anoikis) apoptosis, inflammation derived by the activation of some cytokines belonging to the IL-1 cytokine family, ECM remodeling, epithelial-to-mesenchymal transition (EMT) and fibrosis. A greater comprehension of the pathophysiological consequences of GrB-mediated multiple activities may favor the design of new therapies aim to inhibit different inflammatory pathological conditions such as inflammaging and age-related diseases, EMT and organ fibrosis.


Assuntos
Granzimas/imunologia , Inflamação/imunologia , Animais , Apoptose , Transição Epitelial-Mesenquimal , Matriz Extracelular , Fibrose , Humanos , Perforina/imunologia
9.
Front Immunol ; 11: 582065, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33013937

RESUMO

The phenotype and function of immune cells that reside at the maternal-fetal interface in humans and mice have been, and still are, extensively studied with the aim to fully comprehend the complex immunology of pregnancy. In pigs, information regarding immune cell phenotypes is limited and mainly focused on early gestation whereas late gestation has not yet been investigated. We designed a unique methodology tailored to the porcine epitheliochorial placenta, which allowed us to address immune phenotypes separately in the maternal endometrium (ME) and fetal placenta (FP) by flow cytometry. In-depth phenotyping of NK cells, non-conventional and conventional T cells within maternal blood (mBld), ME, FP, and fetal spleen (fSpln) revealed major differences between these anatomic sites. In both maternal compartments, all NK cells were perforin+ and had NKp46-defined phenotypes indicative of late-stage differentiation. Likewise, T cells with a highly differentiated phenotype including CD2+CD8α+CD27dim/-perforin+ γδ T cells, CD27-perforin+ cytolytic T cells (CTLs), and T-bet+ CD4+CD8α+CD27- effector memory T (Tem) cells prevailed within these compartments. The presence of highly differentiated T cells was also reflected in the number of cells that had the capacity to produce IFN-γ. In the FP, we found NK cells and T cell populations with a naive phenotype including CD2+CD8α-CD27+perforin- γδ T cells, T-bet-CD4+CD8α-CD27+ T cells, and CD27+perforin- CTLs. However, also non-naive T cell phenotypes including CD2+CD8α+CD27+perforin- γδ T cells, T-bet+CD4+CD8α+CD27- Tem cells, and a substantial proportion of CD27-perforin+ CTLs resided within this anatomic site. Currently, the origin or the cues that steer the differentiation of these putative effector cells are unclear. In the fSpln, NKp46high NK cells and T cells with a naive phenotype prevailed. This study demonstrated that antigen-experienced immune cell phenotypes reside at the maternal-fetal interface, including the FP. Our methodology and our findings open avenues to study NK and T cell function over the course of gestation. In addition, this study lays a foundation to explore the interplay between immune cells and pathogens affecting swine reproduction.


Assuntos
Diferenciação Celular/imunologia , Células Matadoras Naturais/imunologia , Relações Materno-Fetais/fisiologia , Linfócitos T/imunologia , Animais , Células Cultivadas , Feminino , Memória Imunológica/imunologia , Leucócitos Mononucleares , Ativação Linfocitária/imunologia , Perforina/imunologia , Placenta/imunologia , Gravidez , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Suínos
10.
Front Immunol ; 11: 1839, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32922397

RESUMO

Gamma delta (GD) T cells are an unconventional T cell type present in both the epidermis and the dermis of human skin. They are critical to regulating skin inflammation, wound healing, and anti-microbial defense. Similar to CD8+ cytotoxic T cells expressing an alpha beta (AB) TCR, GD T cells have cytolytic capabilities. They play an important role in elimination of cutaneous tumors and virally infected cells and have also been implicated in pathogenicity of several autoimmune diseases. T cell cytotoxicity is associated with the expression of the pore forming protein Perforin. Perforin is an innate immune protein containing a membrane attack complex perforin-like (MACPF) domain and functions by forming pores in the membranes of target cells, which allow granzymes and reactive oxygen species to enter the cells and destroy them. Perforin-2, encoded by the gene MPEG1, is a newly discovered member of this protein family that is critical for clearance of intracellular bacteria. Cutaneous GD T cells express both Perforin and Perforin-2, but many questions remain regarding the role that these proteins play in GD T cell mediated cytotoxicity against tumors and bacterial pathogens. Here, we review what is known about Perforin expression by skin GD T cells and the mechanisms that contribute to Perforin activation.


Assuntos
Citotoxicidade Imunológica/imunologia , Linfócitos Intraepiteliais/imunologia , Perforina/imunologia , Animais , Humanos , Linfócitos Intraepiteliais/metabolismo , Perforina/biossíntese
11.
Exp Cell Res ; 396(1): 112260, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32890458

RESUMO

CD8+ T cells are considered a critical component of antitumor immunity. However, tumor-infiltrating CD8+ T cells may express more than one checkpoint molecules that have the potential to inhibit effector responses alone or cooperatively. Here, we focused on the expression dynamic of TIGIT and PD-1 in CD8+ T cells. TIGIT+ subset presented significantly higher PD-1 expression than TIGIT- subset in circulating CD8+ T cells. The expression dynamic of TIGIT and PD-1 was then tracked. In total CD8+ T cells, TIGIT mRNA increased more rapidly than PD-1 mRNA, and TIGIT+ CD8+ T cells upregulated PD-1 more rapidly than TIGIT- CD8+ T cells. Next, 24-h-stimulated CD8+ T cells were re-sorted into TIGIT+ and TIGIT- subsets, and the TIGIT+ cells that came from TIGIT- cells also presented significantly more rapid PD-1 induction than persistent TIGIT- CD8+ T cells. In non-small cell lung cancer (NSCLC) patients, the expression of PD-1 was more enriched in TIGIT+ cells than in TIGIT- cells in both circulating CD8+ T cells and tumor-infiltrating CD8+ T cells. Function analysis revealed that TIGIT+ CD8 T cells presented lower interferon-gamma, perforin 1, and granzyme B upregulation than TIGIT- CD8 T cells, especially in NSCLC patients. Overall, these data indicated that TIGIT presented earlier expression dynamic than PD-1 in activated CD8+ T cells and was upregulated in NSCLC patients.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Carcinoma Pulmonar de Células não Pequenas/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/genética , Receptor de Morte Celular Programada 1/genética , Receptores Imunológicos/genética , Linfócitos T CD8-Positivos/patologia , Carcinoma Pulmonar de Células não Pequenas/imunologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Estudos de Casos e Controles , Feminino , Granzimas/genética , Granzimas/imunologia , Humanos , Imunofenotipagem , Interferon gama/genética , Interferon gama/imunologia , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/patologia , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Perforina/genética , Perforina/imunologia , Cultura Primária de Células , Receptor de Morte Celular Programada 1/imunologia , Receptores Imunológicos/imunologia , Transdução de Sinais
12.
Eur J Immunol ; 50(12): 1952-1958, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32734619

RESUMO

NK1.1+ cells found in salivary glands (SG) represent a unique cell population of innate lymphoid cells (ILC) with characteristics of both conventional NK cells and ILC1. Here, we demonstrate that these NK1.1+  cells limit the accumulation and differentiation of virus-specific tissue-resident memory CD8+ T cells (TRM  cells) in SG of mice infected with lymphocytic choriomeningitis virus (LCMV). The negative regulation of LCMV-specific CD8+ TRM  cells by NK1.1+  cells in SG is independent of NKG2D, NKp46, TRAIL, and perforin. Moreover, analysis of NKp46iCre+ Eomesfl/fl mice revealed that Eomes-dependent conventional NK cells are dispensable for negative regulation. Since the SG are prone to autoimmune reactions, regulation of TRM  cells by tissue-resident ILC may be particularly important to prevent immunopathology in this organ.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Imunidade Inata/imunologia , Memória Imunológica/imunologia , Células Matadoras Naturais/imunologia , Glândulas Salivares/imunologia , Animais , Diferenciação Celular/imunologia , Coriomeningite Linfocítica/imunologia , Vírus da Coriomeningite Linfocítica/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Subfamília K de Receptores Semelhantes a Lectina de Células NK/imunologia , Receptor 1 Desencadeador da Citotoxicidade Natural/imunologia , Perforina/imunologia , Ligante Indutor de Apoptose Relacionado a TNF/imunologia
13.
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 , COVID-19 , Teste para COVID-19 , 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 , SARS-CoV-2 , Índice de Gravidade de Doença , Linfócitos T Citotóxicos/patologia , Linfócitos T Citotóxicos/virologia
14.
Eur J Immunol ; 50(11): 1770-1782, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32419134

RESUMO

Familial hemophagocytic lymphohistiocytosis (FHL) is a hyperinflammatory syndrome affecting patients with genetic cytotoxicity defects. Perforin-deficient (PKO) mice recapitulate the full clinical picture of FHL after infection with lymphocytic choriomeningitis virus (LCMV). Hyperactivated CD8+ T cells and IFN-γ have been identified as the key drivers of FHL and represent targets for therapeutic interventions. However, the response of patients is variable. This could be due to trigger-dependent differences in pathogenesis, which is difficult to address in FHL patients, since the trigger frequently escapes detection. We established an alternative FHL model using intravenous infection of PKO mice with murine CMV (MCMV)Smith . PKO mice developed acute FHL after both infections and fulfilled HLH diagnostic criteria accompanied by excessive IFN-γ production by disease-inducing T cells, that enrich in the BM. However, direct comparison of the two infection models disclosed trigger-dependence of FHL progression and revealed a higher contribution of CD4 T cells and NK cells to IFN-γ production after MCMV infection. Importantly, therapeutic intervention by IFN-γ neutralization or CD8+ T-cell depletion had less benefit in MCMV-triggered FHL compared to LCMV-triggered FHL, likely due to MCMV-induced cytopathology. Thus, the context of the specific triggering viral infection can impact the success of targeted immunotherapeutic HLH control.


Assuntos
Linfo-Histiocitose Hemofagocítica/imunologia , Animais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Modelos Animais de Doenças , Interferon gama/imunologia , Células Matadoras Naturais/imunologia , Ativação Linfocitária/imunologia , Coriomeningite Linfocítica/imunologia , Vírus da Coriomeningite Linfocítica/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Perforina/imunologia , Resultado do Tratamento
16.
Clin Infect Dis ; 71(16): 2272-2275, 2020 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-32407466

RESUMO

Increased production of inflammatory cytokines and myeloid-derived suppressor cells occurs in patients with coronavirus disease 2019. These inversely correlated with perforin-expressing natural killer (NK) and CD3+ T cells. We observed a lower number of perforin-expressing NK cells in intensive care unit (ICU) patients compared with non-ICU patients, suggesting an impairment of the immune cytotoxic arm as a pathogenic mechanism.


Assuntos
COVID-19/imunologia , Inflamação/sangue , Células Matadoras Naturais/imunologia , Perforina/imunologia , Linfócitos T Citotóxicos/imunologia , Idoso , COVID-19/sangue , Citocinas/imunologia , Feminino , Humanos , Inflamação/complicações , Inflamação/imunologia , Unidades de Terapia Intensiva/estatística & dados numéricos , Itália , Ativação Linfocitária/imunologia , Masculino , Pessoa de Meia-Idade , SARS-CoV-2
17.
J Struct Biol ; 211(2): 107531, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32446810

RESUMO

The Membrane Attack Complex-Perforin (MACPF) family is ubiquitously found in all kingdoms. They have diverse cellular roles, however MACPFs with pore-forming toxic function in venoms and poisons are very rare in animals. Here we present the structure of PmPV2, a MACPF toxin from the poisonous apple snail eggs, that can affect the digestive and nervous systems of potential predators. We report the three-dimensional structure of PmPV2, at 17.2 Å resolution determined by negative-stain electron microscopy and its solution structure by small angle X-ray scattering (SAXS). We found that PV2s differ from nearly all MACPFs in two respects: it is a dimer in solution and protomers combine two immune proteins into an AB toxin. The MACPF chain is linked by a single disulfide bond to a tachylectin chain, and two heterodimers are arranged head-to-tail by non-covalent forces in the native protein. MACPF domain is fused with a putative new Ct-accessory domain exclusive to invertebrates. The tachylectin is a six-bladed ß-propeller, similar to animal tectonins. We experimentally validated the predicted functions of both subunits and demonstrated for the first time that PV2s are true pore-forming toxins. The tachylectin "B" delivery subunit would bind to target membranes, and then the MACPF "A" toxic subunit would disrupt lipid bilayers forming large pores altering the plasma membrane conductance. These results indicate that PV2s toxicity evolved by linking two immune proteins where their combined preexisting functions gave rise to a new toxic entity with a novel role in defense against predation. This structure is an unparalleled example of protein exaptation.


Assuntos
Complexo de Ataque à Membrana do Sistema Complemento/ultraestrutura , Lectinas/ultraestrutura , Perforina/ultraestrutura , Conformação Proteica , Sequência de Aminoácidos/genética , Animais , Membrana Celular/química , Membrana Celular/ultraestrutura , Complexo de Ataque à Membrana do Sistema Complemento/química , Complexo de Ataque à Membrana do Sistema Complemento/imunologia , Cristalografia por Raios X , Dimerização , Lectinas/química , Lectinas/imunologia , Modelos Moleculares , Perforina/química , Perforina/imunologia , Subunidades Proteicas/genética , Espalhamento a Baixo Ângulo , Caramujos/ultraestrutura , Difração de Raios X
18.
Genes Immun ; 21(3): 169-181, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32291394

RESUMO

Macrophage activation syndrome (MAS), or secondary hemophagocytic lymphohistiocytosis (HLH), is a cytokine storm syndrome associated with multi-organ system dysfunction and high mortality rates. Laboratory and clinical features resemble primary HLH, which arises in infancy (1 in 50,000 live births) from homozygous mutations in various genes critical to the perforin-mediated cytolytic pathway employed by NK cells and cytotoxic CD8 T lymphocytes. MAS/secondary HLH is about ten times more common and typically presents beyond infancy extending into adulthood. The genetics of MAS are far less defined than for familial HLH. However, the distinction between familial HLH and MAS/secondary HLH is blurred by the finding of heterozygous perforin-pathway mutations in MAS patients, which may function as hypomorphic or partial dominant-negative alleles and contribute to disease pathogenesis. In addition, mutations in a variety of other pathogenic pathways have been noted in patients with MAS/secondary HLH. Many of these genetically disrupted pathways result in a similar cytokine storm syndrome, and can be broadly categorized as impaired viral control (e.g., SH2P1A), dysregulated inflammasome activity (e.g., NLRC4), other immune defects (e.g., IKBKG), and dysregulated metabolism (e.g., LIPA). Collectively these genetic lesions likely combine with states of chronic inflammation, as seen in various rheumatic diseases (e.g., still disease), with or without identified infections, to result in MAS pathology as explained by the threshold model of disease. This emerging paradigm may ultimately support genetic risk stratification for high-risk chronic and even acute inflammatory disorders. Moving forward, continued whole-exome and -genome sequencing will likely identify novel MAS gene associations, as well as noncoding mutations altering levels of gene expression.


Assuntos
Inflamassomos/genética , Linfo-Histiocitose Hemofagocítica/genética , Linfo-Histiocitose Hemofagocítica/imunologia , Síndrome de Ativação Macrofágica/genética , Síndrome de Ativação Macrofágica/imunologia , Viroses/genética , Linfócitos T CD8-Positivos/imunologia , Predisposição Genética para Doença , Heterozigoto , Humanos , Inflamassomos/imunologia , Células Matadoras Naturais/imunologia , Mutação , Perforina/imunologia , Viroses/imunologia
19.
Comb Chem High Throughput Screen ; 23(5): 381-391, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32264809

RESUMO

BACKGROUND: Tumor microenvironment (TME) cells play important roles in tumor progression. Accumulating evidence show that they can be exploited to predict the clinical outcomes and therapeutic responses of the tumor. However, the role of immune genes of TME in small cell lung cancer (SCLC) is currently unknown. OBJECTIVE: To determine the role of immune genes in SCLC. METHODS: We downloaded the expression profile and clinical follow-up data of SCLC patients from Gene Expression Omnibus (GEO), and TME infiltration profile data of 158 patients using CIBERSORT. The correlation between TME phenotypes, genomic features, and clinicopathological features of SCLC was examined. A gene signature was constructed based on TME genes to further evaluate the relationship between molecular subtypes of SCLC with the prognosis and clinical features. RESULTS: We identified a group of genes that are highly associated with TME. Several immune cells in TME cells were significantly correlated with SCLC prognosis (p<0.0001). These immune cells displayed diverse immune patterns. Three molecular subtypes of SCLC (TMEC1-3) were identified on the basis of enrichment of immune cell components, and these subtypes showed dissimilar prognosis profiles (p=0.03). The subtype with the best prognosis, TMEC3, was enriched with immune activation factors such as oncogene M0, oncogene M2, T cells follicular helper, and T cells CD8 (p<0.001). The TMEC1 subtype with the worst prognosis was enriched with T cells CD4 naive, B cells memory and Dendritic cells activated cells (p<0.001). Further analysis showed that the TME was significantly enriched with immune checkpoint genes, immune genes, and immune pathway genes (p<0.01). From the gene expression data, we identified four TME-related genes, GZMB, HAVCR2, PRF1 and TBX2, which were significantly associated with poor prognosis in both the training set and the validation set (p<0.05). These genes may serve as markers for monitoring tumor responses to immune checkpoint inhibitors. CONCLUSION: This study shows that TME features may serve as markers for evaluating the response of SCLC cells to immunotherapy.


Assuntos
Biomarcadores Tumorais/genética , Biologia Computacional , Neoplasias Pulmonares/genética , Carcinoma de Pequenas Células do Pulmão/genética , Biomarcadores Tumorais/imunologia , Granzimas/genética , Granzimas/imunologia , Receptor Celular 2 do Vírus da Hepatite A/genética , Receptor Celular 2 do Vírus da Hepatite A/imunologia , Humanos , Perforina/genética , Perforina/imunologia , Proteínas com Domínio T/genética , Proteínas com Domínio T/imunologia , Microambiente Tumoral
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