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1.
Front Immunol ; 11: 1870, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32983106

RESUMO

Coronavirus disease 2019 (COVID-19) which is caused by the novel SARS-CoV-2 virus is a severe flu-like illness which is associated with hyperinflammation and immune dysfunction. The virus induces a strong T and B cell response but little is known about the immune pathology of this viral infection. Acute Plasmodium falciparum malaria also causes acute clinical illness and is characterized by hyperinflammation due to the strong production of pro-inflammatory cytokines and a massive activation of T cells. In malaria, T cells express a variety of co-inhibitory receptors which might be a consequence of their activation but also might limit their overwhelming function. Thus, T cells are implicated in protection as well as in pathology. The outcome of malaria is thought to be a consequence of the balance between co-activation and co-inhibition of T cells. Following the hypothesis that T cells in COVID-19 might have a similar, dual function, we comprehensively characterized the differentiation (CCR7, CD45RO) and activation status (HLA-DR, CD38, CD69, CD226), the co-expression of co-inhibitory molecules (PD1, TIM-3, LAG-3, BTLA, TIGIT), as well as the expression pattern of the transcription factors T-bet and eomes of CD8+ and CD4+ T cells of PBMC of n = 20 SARS-CoV-2 patients compared to n = 10 P. falciparum infected patients and n = 13 healthy controls. Overall, acute COVID-19 and malaria infection resulted in a comparably elevated activation and altered differentiation status of the CD8+ and CD4+ T cell populations. T effector cells of COVID-19 and malaria patients showed higher frequencies of the inhibitory receptors T-cell immunoglobulin mucin-3 (TIM-3) and Lymphocyte-activation gene-3 (LAG-3) which was linked to increased activation levels and an upregulation of the transcription factors T-bet and eomes. COVID-19 patients with a more severe disease course showed higher levels of LAG-3 and TIM-3 than patients with a mild disease course. During recovery, a rapid normalization of these inhibitory receptors could be observed. In summary, comparing the expression of different co-inhibitory molecules in CD8+ and CD4+ T cells in COVID-19 vs. malaria, there is a transient increase of the expression of certain inhibitory receptors like LAG-3 and TIM-3 in COVID-19 in the overall context of acute immune activation.


Assuntos
Antígenos CD/metabolismo , Betacoronavirus/genética , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Infecções por Coronavirus/imunologia , Receptor Celular 2 do Vírus da Hepatite A/metabolismo , Ativação Linfocitária/imunologia , Malária Falciparum/imunologia , Plasmodium falciparum/isolamento & purificação , Pneumonia Viral/imunologia , Receptores de Antígenos de Linfócitos T/metabolismo , Doença Aguda , Adulto , Idoso , Células Cultivadas , Estudos de Coortes , Infecções por Coronavirus/virologia , Feminino , Humanos , Malária Falciparum/parasitologia , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/virologia , Receptor de Morte Celular Programada 1/metabolismo , Índice de Gravidade de Doença
2.
Nature ; 585(7824): 277-282, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32879489

RESUMO

Abnormal epigenetic patterns correlate with effector T cell malfunction in tumours1-4, but the cause of this link is unknown. Here we show that tumour cells disrupt methionine metabolism in CD8+ T cells, thereby lowering intracellular levels of methionine and the methyl donor S-adenosylmethionine (SAM) and resulting in loss of dimethylation at lysine 79 of histone H3 (H3K79me2). Loss of H3K79me2 led to low expression of STAT5 and impaired T cell immunity. Mechanistically, tumour cells avidly consumed methionine and outcompeted T cells for methionine by expressing high levels of the methionine transporter SLC43A2. Genetic and biochemical inhibition of tumour SLC43A2 restored H3K79me2 in T cells, thereby boosting spontaneous and checkpoint-induced tumour immunity. Moreover, methionine supplementation improved the expression of H3K79me2 and STAT5 in T cells, and this was accompanied by increased T cell immunity in tumour-bearing mice and patients with colon cancer. Clinically, tumour SLC43A2 correlated negatively with T cell histone methylation and functional gene signatures. Our results identify a mechanistic connection between methionine metabolism, histone patterns, and T cell immunity in the tumour microenvironment. Thus, cancer methionine consumption is an immune evasion mechanism, and targeting cancer methionine signalling may provide an immunotherapeutic approach.


Assuntos
Sistema L de Transporte de Aminoácidos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Histonas/metabolismo , Metionina/metabolismo , Metilação , Neoplasias/metabolismo , Sistema L de Transporte de Aminoácidos/deficiência , Animais , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/imunologia , Linhagem Celular Tumoral , Epigênese Genética , Feminino , Histonas/química , Humanos , Camundongos , Neoplasias/genética , Neoplasias/imunologia , Neoplasias/patologia , Receptores de Antígenos de Linfócitos T/metabolismo , Fator de Transcrição STAT5/metabolismo
3.
Nat Commun ; 11(1): 4166, 2020 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-32820173

RESUMO

T cells engineered to express chimeric antigen receptors (CAR-T cells) have shown impressive clinical efficacy in the treatment of B cell malignancies. However, the development of CAR-T cell therapies for solid tumors is hampered by the lack of truly tumor-specific antigens and poor control over T cell activity. Here we present an avidity-controlled CAR (AvidCAR) platform with inducible and logic control functions. The key is the combination of (i) an improved CAR design which enables controlled CAR dimerization and (ii) a significant reduction of antigen-binding affinities to introduce dependence on bivalent interaction, i.e. avidity. The potential and versatility of the AvidCAR platform is exemplified by designing ON-switch CARs, which can be regulated with a clinically applied drug, and AND-gate CARs specifically recognizing combinations of two antigens. Thus, we expect that AvidCARs will be a highly valuable platform for the development of controllable CAR therapies with improved tumor specificity.


Assuntos
Imunoterapia Adotiva/métodos , Receptores de Antígenos de Linfócitos T/imunologia , Receptores de Antígenos Quiméricos/imunologia , Linfócitos T/imunologia , Animais , Antígenos de Neoplasias/imunologia , Linfócitos B/imunologia , Linfócitos B/metabolismo , Células Cultivadas , Citocinas/imunologia , Citocinas/metabolismo , Citotoxicidade Imunológica/imunologia , Humanos , Ativação Linfocitária/imunologia , Camundongos Endogâmicos NOD , Camundongos Knockout , Camundongos SCID , Neoplasias/imunologia , Neoplasias/patologia , Neoplasias/terapia , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/metabolismo , Receptores de Antígenos Quiméricos/genética , Receptores de Antígenos Quiméricos/metabolismo , Linfócitos T/metabolismo
4.
Nat Commun ; 11(1): 3755, 2020 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-32709874

RESUMO

Obesity is associated with low-grade chronic inflammation promoting insulin-resistance and diabetes. Gut microbiota dysbiosis is a consequence as well as a driver of obesity and diabetes. Mucosal-associated invariant T cells (MAIT) are innate-like T cells expressing a semi-invariant T cell receptor restricted to the non-classical MHC class I molecule MR1 presenting bacterial ligands. Here we show that during obesity MAIT cells promote inflammation in both adipose tissue and ileum, leading to insulin resistance and impaired glucose and lipid metabolism. MAIT cells act in adipose tissue by inducing M1 macrophage polarization in an MR1-dependent manner and in the gut by inducing microbiota dysbiosis and loss of gut integrity. Both MAIT cell-induced tissue alterations contribute to metabolic dysfunction. Treatment with MAIT cell inhibitory ligand demonstrates its potential as a strategy against inflammation, dysbiosis and metabolic disorders.


Assuntos
Disbiose/imunologia , Inflamação/patologia , Intestinos/patologia , Células T Invariáveis Associadas à Mucosa/patologia , Obesidade/metabolismo , Tecido Adiposo/patologia , Animais , Citocinas/genética , Citocinas/metabolismo , Dieta Hiperlipídica , Disbiose/complicações , Microbioma Gastrointestinal , Teste de Tolerância a Glucose , Íleo/patologia , Inflamação/complicações , Mucosa Intestinal/patologia , Intestinos/diagnóstico por imagem , Ligantes , Contagem de Linfócitos , Macrófagos/metabolismo , Imagem por Ressonância Magnética , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/complicações , Obesidade/diagnóstico por imagem , Fenótipo , Pterinas/farmacologia , Receptores de Antígenos de Linfócitos T/metabolismo
5.
Proc Natl Acad Sci U S A ; 117(32): 19388-19398, 2020 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-32727906

RESUMO

CD8+ T cells play pivotal roles in eradicating pathogens and tumor cells. T cell receptor (TCR) signaling is vital for the optimal activation of CD8+ T cells. Upon TCR engagement, the transmembrane adapter protein LAT (linker for activation of T cells) recruits other key signaling molecules and forms the "LAT signalosome" for downstream signal transduction. However, little is known about which functional partners could restrain the formation of the LAT signalosome and inhibit CD8+ cytotoxic T lymphocyte (CTL)-mediated cytotoxicity. Here we have demonstrated that LRCH1 (leucine-rich repeats and calponin homology domain containing 1) directly binds LAT, reduces LAT phosphorylation and interaction with GRB2, and also promotes the endocytosis of LAT. Lrch1 -/- mice display better protection against influenza virus and Listeria infection, with enhanced CD8+ T cell proliferation and cytotoxicity. Adoptive transfer of Lrch1 -/- CD8+ CTLs leads to increased B16-MO5 tumor clearance in vivo. Furthermore, knockout of LRCH1 in human chimeric antigen receptor (CAR) T cells that recognize the liver tumor-associated antigen glypican-3 could improve CAR T cell migration and proliferation in vitro. These findings suggest LRCH1 as a potential translational target to improve T cell immunotherapy against infection and tumors.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Linfócitos T CD8-Positivos/imunologia , Proteínas de Membrana/metabolismo , Proteínas dos Microfilamentos/deficiência , Transdução de Sinais , Animais , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/transplante , Movimento Celular , Células Cultivadas , Citotoxicidade Imunológica , Endocitose , Proteína Adaptadora GRB2/metabolismo , Humanos , Imunoterapia Adotiva , Infecções/imunologia , Infecções/microbiologia , Infecções/virologia , Interferon gama/metabolismo , Neoplasias Pulmonares/terapia , Ativação Linfocitária , Camundongos , Camundongos Knockout , Proteínas dos Microfilamentos/genética , Proteínas dos Microfilamentos/metabolismo , Fosforilação , Ligação Proteica , Receptores de Antígenos de Linfócitos T/metabolismo , Receptores de Antígenos Quiméricos/metabolismo
6.
Nat Commun ; 11(1): 2779, 2020 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-32487999

RESUMO

T cell receptor (TCR) activation is modulated by mechanisms such as TCR endocytosis, which is thought to terminate TCR signalling. Here we show that, upon internalization, TCR continues to signal from a set of specialized endosomes that are crucial for T cell functions. Mechanistically, TCR ligation leads to clathrin-mediated internalization of the TCR-CD3ζ complex, while maintaining CD3ζ signalling, in endosomal vesicles that contain the insulin responsive aminopeptidase (IRAP) and the SNARE protein Syntaxin 6. Destabilization of this compartment through IRAP deletion enhances plasma membrane expression of the TCR-CD3ζ complex, yet compromises overall CD3ζ signalling; moreover, the integrity of this compartment is also crucial for T cell activation and survival after suboptimal TCR activation, as mice engineered with a T cell-specific deletion of IRAP fail to develop efficient polyclonal anti-tumour responses. Our results thus reveal a previously unappreciated function of IRAP-dependent endosomal TCR signalling in T cell activation.


Assuntos
Cistinil Aminopeptidase/metabolismo , Endossomos/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Transdução de Sinais/fisiologia , Linfócitos T/metabolismo , Animais , Membrana Celular/metabolismo , Proliferação de Células , Clatrina/metabolismo , Cistinil Aminopeptidase/genética , Modelos Animais de Doenças , Endocitose/fisiologia , Células HEK293 , Humanos , Interleucina-2/metabolismo , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Qa-SNARE/metabolismo , Transcriptoma
7.
Nat Commun ; 11(1): 2908, 2020 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-32518267

RESUMO

Adoptive cell therapy (ACT) with tumor-specific T cells can mediate cancer regression. The main target of tumor-specific T cells are neoantigens arising from mutations in self-proteins. Although the majority of cancer neoantigens are unique to each patient, and therefore not broadly useful for ACT, some are shared. We studied oligoclonal T-cell receptors (TCRs) that recognize a shared neoepitope arising from a driver mutation in the p53 oncogene (p53R175H) presented by HLA-A2. Here we report structures of wild-type and mutant p53-HLA-A2 ligands, as well as structures of three tumor-specific TCRs bound to p53R175H-HLA-A2. These structures reveal how a driver mutation in p53 rendered a self-peptide visible to T cells. The TCRs employ structurally distinct strategies that are highly focused on the mutation to discriminate between mutant and wild-type p53. The TCR-p53R175H-HLA-A2 complexes provide a framework for designing TCRs to improve potency for ACT without sacrificing specificity.


Assuntos
Antígenos de Neoplasias/química , Antígeno HLA-A2/química , Mutação , Linfócitos T/imunologia , Proteína Supressora de Tumor p53/química , Sítios de Ligação , Biotinilação , Códon , Cristalografia por Raios X , Epitopos , Escherichia coli/metabolismo , Humanos , Imunoterapia Adotiva , Ligantes , Linfócitos do Interstício Tumoral/imunologia , Neoplasias/metabolismo , Peptídeos/química , Ligação Proteica , Conformação Proteica , Dobramento de Proteína , Receptores de Antígenos de Linfócitos T/metabolismo , Software , Ressonância de Plasmônio de Superfície
8.
Nat Commun ; 11(1): 3187, 2020 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-32581235

RESUMO

The application of adoptive T cell therapies, including those using chimeric antigen receptor (CAR)-modified T cells, to solid tumors requires combinatorial strategies to overcome immune suppression associated with the tumor microenvironment. Here we test whether the inflammatory nature of oncolytic viruses and their ability to remodel the tumor microenvironment may help to recruit and potentiate the functionality of CAR T cells. Contrary to our hypothesis, VSVmIFNß infection is associated with attrition of murine EGFRvIII CAR T cells in a B16EGFRvIII model, despite inducing a robust proinflammatory shift in the chemokine profile. Mechanistically, type I interferon (IFN) expressed following infection promotes apoptosis, activation, and inhibitory receptor expression, and interferon-insensitive CAR T cells enable combinatorial therapy with VSVmIFNß. Our study uncovers an unexpected mechanism of therapeutic interference, and prompts further investigation into the interaction between CAR T cells and oncolytic viruses to optimize combination therapy.


Assuntos
Imunoterapia Adotiva , Interferon beta/metabolismo , Vírus Oncolíticos/metabolismo , Receptores de Antígenos Quiméricos/metabolismo , Linfócitos T/metabolismo , Animais , Apoptose , Linhagem Celular Tumoral , Quimiocinas/metabolismo , Terapia Combinada , Feminino , Interferon beta/genética , Ativação Linfocitária , Melanoma Experimental/imunologia , Melanoma Experimental/terapia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Terapia Viral Oncolítica , Vírus Oncolíticos/genética , Receptor de Interferon alfa e beta/genética , Receptor de Interferon alfa e beta/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Baço/imunologia
9.
Mol Immunol ; 123: 64-73, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32422416

RESUMO

T cells can help confer protective immunity by eliminating infections and tumors or drive immunopathology by damaging host cells. Both outcomes require a series of steps from the activation of naïve T cells to their clonal expansion, differentiation and migration to tissue sites. In addition to specific recognition of the antigen via the T cell receptor (TCR), multiple accessory signals from costimulatory molecules, cytokines and metabolites also influence each step along the progression of the T cell response. Current efforts to modify effector T cell function in many clinical contexts focus on the latter - which encompass antigen-independent and broad, contextual regulators. Not surprisingly, such approaches are often accompanied by adverse events, as they also affect T cells not relevant to the specific treatment. In contrast, fine tuning T cell responses by precisely targeting antigen-specific TCR signals has the potential to radically alter therapeutic strategies in a focused manner. Development of such approaches, however, requires a better understanding of functioning of the TCR and the biochemical signaling network coupled to it. In this article, we review some of the recent advances which highlight important roles of TCR signals throughout the activation and differentiation of T cells during an immune response. We discuss how, an appreciation of specific signaling modalities and variant ligands that influence the function of the TCR has the potential to influence design principles for the next generation of pharmacologic and cellular therapies, especially in the context of tumor immunotherapies involving adoptive cell transfers.


Assuntos
Transferência Adotiva/métodos , Imunidade Celular/fisiologia , Receptores de Antígenos de Linfócitos T/fisiologia , Linfócitos T/imunologia , Linfócitos T/metabolismo , Animais , Células Apresentadoras de Antígenos/imunologia , Diferenciação Celular/imunologia , Humanos , Imunoterapia/métodos , Ativação Linfocitária , Neoplasias/imunologia , Neoplasias/terapia , Receptores de Antígenos de Linfócitos T/metabolismo , Receptores de Antígenos Quiméricos/imunologia , Receptores de Antígenos Quiméricos/metabolismo , Transdução de Sinais/imunologia
10.
Proc Natl Acad Sci U S A ; 117(23): 12969-12979, 2020 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-32434911

RESUMO

CD5 is characterized as an inhibitory coreceptor with an important regulatory role during T cell development. The molecular mechanism by which CD5 operates has been puzzling and its function in mature T cells suggests promoting rather than repressing effects on immune responses. Here, we combined quantitative mass spectrometry and genetic studies to analyze the components and the activity of the CD5 signaling machinery in primary T cells. We found that T cell receptor (TCR) engagement induces the selective phosphorylation of CD5 tyrosine 429, which serves as a docking site for proteins with adaptor functions (c-Cbl, CIN85, CRKL), connecting CD5 to positive (PI3K) and negative (UBASH3A, SHIP1) regulators of TCR signaling. c-CBL acts as a coordinator in this complex enabling CD5 to synchronize positive and negative feedbacks on TCR signaling through the other components. Disruption of CD5 signalosome in mutant mice reveals that it modulates TCR signal outputs to selectively repress the transactivation of Foxp3 and limit the inopportune induction of peripherally induced regulatory T cells during immune responses against foreign antigen. Our findings bring insights into the paradigm of coreceptor signaling, suggesting that, in addition to providing dualistic enhancing or dampening inputs, coreceptors can engage concomitant stimulatory and inhibitory signaling events, which act together to promote specific functional outcomes.


Assuntos
Antígenos/imunologia , Antígenos CD5/metabolismo , Diferenciação Celular/imunologia , Receptores de Antígenos de Linfócitos T/metabolismo , Linfócitos T Reguladores/fisiologia , Animais , Antígenos CD5/genética , Diferenciação Celular/genética , Regulação da Expressão Gênica/imunologia , Ativação Linfocitária/genética , Espectrometria de Massas , Camundongos , Camundongos Transgênicos , Cultura Primária de Células , Receptores de Antígenos de Linfócitos T/antagonistas & inibidores , Transdução de Sinais/genética , Transdução de Sinais/imunologia
11.
Mol Carcinog ; 59(7): 713-723, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32391973

RESUMO

Chimeric antigen receptor (CAR) T-cells treatment demonstrate the increasing and powerful potential of immunotherapeutic strategies, as seen mainly for hematological malignancies. Still, efficient CAR-T cell approaches for the treatment of a broader spectrum of tumors are needed. It has been shown that cancer cells can implement strategies to evade immune response that include the expression of inhibitory ligands, such as hypersialylated proteins (sialoglycans) on their surface. These may be recognized by sialic acid-binding immunoglobulin-type lectins (siglecs) which are surface receptors found primarily on immune cells. In this regard, siglec-7 and -9 are found on immune cells, such as natural killer cells, T-cells, and dendritic cells and they can promote immune suppression when binding to sialic acids expressed on target cells. In the present study, we hypothesized that it is possible to use genetically engineered T-cells expressing siglec-based CARs, enabling them to recognize and eliminate tumor cells, in a non-histocompatibility complex molecule restricted way. Thus, we genetically modified human T-cells with different chimeric receptors based on the exodomain of human siglec-7 and -9 molecules and selected optimal receptors. We then assessed their antitumor activity in vitro demonstrating the recognition of cell lines from different histologies. These results were confirmed in a tumor xenograft model exemplifying the potential of the present approach. Overall, this study demonstrates the benefit of targeting cancer-associated glycosylation patterns using CAR based on native immune receptors and expressed in human primary T-cells.


Assuntos
Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/metabolismo , Lectinas/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Lectinas Semelhantes a Imunoglobulina de Ligação ao Ácido Siálico/metabolismo , Linfócitos T/metabolismo , Animais , Linhagem Celular , Linhagem Celular Tumoral , Glicosilação , Células HEK293 , Células HeLa , Xenoenxertos/metabolismo , Humanos , Células Jurkat , Células K562 , Leucócitos Mononucleares/metabolismo , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID
12.
Nucleic Acids Res ; 48(11): 5873-5890, 2020 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-32392347

RESUMO

The chromatin organizer SATB1 is highly enriched in thymocytes and is essential for T-cell development. Although SATB1 regulates a large number of genes important for T-cell development, the mechanism(s) regulating expression of SATB1 during this process remain elusive. Using chromatin immune precipitation-seq-based occupancy profiles of H3K4me3 and H3Kme1 at Satb1 gene locus, we predicted four different alternative promoters of Satb1 in mouse thymocytes and characterized them. The expression of Satb1 transcript variants with distinct 5' UTRs occurs in a stage-specific manner during T-cell development and is dependent on TCR signaling. The observed discrepancy between the expression levels of SATB1 mRNA and protein in developing thymocytes can be explained by the differential translatability of Satb1 transcript variants as confirmed by polysome profiling and in vitro translation assay. We show that Satb1 alternative promoters exhibit lineage-specific chromatin accessibility during T-cell development from progenitors. Furthermore, TCF1 regulates the Satb1 P2 promoter switch during CD4SP development, via direct binding to the Satb1 P2 promoter. CD4SP T cells from TCF1 KO mice exhibit downregulation of P2 transcript variant expression as well as low levels of SATB1 protein. Collectively, these results provide unequivocal evidence toward alternative promoter switch-mediated developmental stage-specific regulation of SATB1 in thymocytes.


Assuntos
Cromatina/metabolismo , Proteínas de Ligação à Região de Interação com a Matriz/genética , Regiões Promotoras Genéticas , Receptores de Antígenos de Linfócitos T/metabolismo , Linfócitos T/citologia , Linfócitos T/metabolismo , Animais , Linfócitos T CD4-Positivos/metabolismo , Diferenciação Celular , Linhagem da Célula , Cromatina/genética , Fator 1-alfa Nuclear de Hepatócito/metabolismo , Proteínas de Ligação à Região de Interação com a Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Biossíntese de Proteínas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais , Timócitos/citologia , Timócitos/metabolismo
13.
Nat Immunol ; 21(6): 684-694, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32231301

RESUMO

Aging is associated with remodeling of the immune system to enable the maintenance of life-long immunity. In the CD8+ T cell compartment, aging results in the expansion of highly differentiated cells that exhibit characteristics of cellular senescence. Here we found that CD27-CD28-CD8+ T cells lost the signaling activity of the T cell antigen receptor (TCR) and expressed a protein complex containing the agonistic natural killer (NK) receptor NKG2D and the NK adaptor molecule DAP12, which promoted cytotoxicity against cells that expressed NKG2D ligands. Immunoprecipitation and imaging cytometry indicated that the NKG2D-DAP12 complex was associated with sestrin 2. The genetic inhibition of sestrin 2 resulted in decreased expression of NKG2D and DAP12 and restored TCR signaling in senescent-like CD27-CD28-CD8+ T cells. Therefore, during aging, sestrins induce the reprogramming of non-proliferative senescent-like CD27-CD28-CD8+ T cells to acquire a broad-spectrum, innate-like killing activity.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Senescência Celular/imunologia , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Proteínas Nucleares/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Citotoxicidade Imunológica , Perfilação da Expressão Gênica , Humanos , Proteínas de Membrana/metabolismo , Subfamília K de Receptores Semelhantes a Lectina de Células NK/metabolismo , Proteínas Nucleares/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Receptores de Células Matadoras Naturais/metabolismo , Transdução de Sinais , Febre Amarela/genética , Febre Amarela/imunologia , Febre Amarela/metabolismo , Febre Amarela/virologia , Vírus da Febre Amarela/imunologia
14.
Cancer Sci ; 111(7): 2223-2233, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32324315

RESUMO

Invariant natural killer T (iNKT) cells are innate-like CD1d-restricted T cells that express the invariant T cell receptor (TCR) composed of Vα24 and Vß11 in humans. iNKT cells specifically recognize glycolipid antigens such as α-galactosylceramide (αGalCer) presented by CD1d. iNKT cells show direct cytotoxicity toward CD1d-positive tumor cells, especially when CD1d presents glycolipid antigens. However, iNKT cell recognition of CD1d-negative tumor cells is unknown, and direct cytotoxicity of iNKT cells toward CD1d-negative tumor cells remains controversial. Here, we demonstrate that activated iNKT cells recognize leukemia cells in a CD1d-independent manner, however still in a TCR-mediated way. iNKT cells degranulated and released Th1 cytokines toward CD1d-negative leukemia cells (K562, HL-60, REH) as well as αGalCer-loaded CD1d-positive Jurkat cells. The CD1d-independent cytotoxicity was enhanced by natural killer cell-activating receptors such as NKG2D, 2B4, DNAM-1, LFA-1 and CD2, but iNKT cells did not depend on these receptors for the recognition of CD1d-negative leukemia cells. In contrast, TCR was essential for CD1d-independent recognition and cytotoxicity. iNKT cells degranulated toward patient-derived leukemia cells independently of CD1d expression. iNKT cells targeted myeloid malignancies more than acute lymphoblastic leukemia. These findings reveal a novel anti-tumor mechanism of iNKT cells in targeting CD1d-negative tumor cells and indicate the potential of iNKT cells for clinical application to treat leukemia independently of CD1d.


Assuntos
Antígenos CD1d/metabolismo , Leucemia/imunologia , Leucemia/metabolismo , Ativação Linfocitária/imunologia , Células T Matadoras Naturais/imunologia , Células T Matadoras Naturais/metabolismo , Animais , Antígenos CD1d/genética , Biomarcadores , Degranulação Celular , Linhagem Celular Tumoral , Receptores Coestimuladores e Inibidores de Linfócitos T/metabolismo , Citocinas/metabolismo , Citotoxicidade Imunológica , Modelos Animais de Doenças , Feminino , Edição de Genes , Xenoenxertos , Humanos , Imunofenotipagem , Leucemia/genética , Leucemia/patologia , Ativação Linfocitária/genética , Camundongos , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/metabolismo , Receptores Desencadeadores da Citotoxicidade Natural/metabolismo
15.
Nat Commun ; 11(1): 1801, 2020 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-32286271

RESUMO

Naïve CD4+ T cells coordinate the immune response by acquiring an effector phenotype in response to cytokines. However, the cytokine responses in memory T cells remain largely understudied. Here we use quantitative proteomics, bulk RNA-seq, and single-cell RNA-seq of over 40,000 human naïve and memory CD4+ T cells to show that responses to cytokines differ substantially between these cell types. Memory T cells are unable to differentiate into the Th2 phenotype, and acquire a Th17-like phenotype in response to iTreg polarization. Single-cell analyses show that T cells constitute a transcriptional continuum that progresses from naïve to central and effector memory T cells, forming an effectorness gradient accompanied by an increase in the expression of chemokines and cytokines. Finally, we show that T cell activation and cytokine responses are influenced by the effectorness gradient. Our results illustrate the heterogeneity of T cell responses, furthering our understanding of inflammation.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Citocinas/farmacologia , Análise de Célula Única , Transcriptoma/genética , Antígenos CD28/metabolismo , Linfócitos T CD4-Positivos/efeitos dos fármacos , Polaridade Celular/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Ativação Linfocitária/efeitos dos fármacos , Ativação Linfocitária/imunologia , Masculino , Pessoa de Meia-Idade , Análise de Componente Principal , Proteoma/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Transcriptoma/efeitos dos fármacos
16.
Scand J Immunol ; 91(6): e12888, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32281665

RESUMO

We propose a framework to explain how T cells achieve specificity and sensitivity, how the affinity of the TcR peptide/MHC interaction controls positive and negative thymic selection and mature T cell survival, and whether antigen-dependent activation and inactivation takes place. Two distinct types of signalling can lead to mature T cell multiplication. One requires the TcR to recognize with a certain affinity an antigen-derived peptide, an agonist peptide, bound to an MHC molecule. The other, the tonic signal, leads to naïve T cell survival and modest proliferation if the T cell successfully competes for endogenous, self-peptide/MHC ligands, involving lower affinity TCR/ligand interactions. Many suggest lymphopenia contributes to autoimmunity by increasing the strength of TcR-tonic signalling, and so activation of anti-self T cells. We suggest T cell activation requires antigen-mediated cooperation between T cells. Increased tonic signalling under lymphopenic conditions facilitates T cell proliferation and so antigen-dependent cooperation and activation of anti-self T cells.


Assuntos
Linfopenia/imunologia , Especificidade do Receptor de Antígeno de Linfócitos T , Linfócitos T/imunologia , Animais , Apresentação do Antígeno , Autoantígenos/imunologia , Autoantígenos/metabolismo , Autoimunidade , Comunicação Celular , Diferenciação Celular , Sobrevivência Celular , Antígenos de Histocompatibilidade/metabolismo , Humanos , Ativação Linfocitária , Modelos Imunológicos , Fragmentos de Peptídeos/imunologia , Fragmentos de Peptídeos/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Transdução de Sinais
17.
J Vis Exp ; (157)2020 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-32250358

RESUMO

Emerging immunotherapies to treat infectious diseases and cancers often involve transduction of cellular populations with genes encoding disease-targeting proteins. For example, chimeric antigen receptor (CAR)-T cells to treat cancers and viral infections involve the transduction of T cells with synthetic genes encoding CAR molecules. The CAR molecules make the T cells specifically recognize and kill cancer or virally infected cells. Cells can also be co-transduced with other genes of interest. For example, cells can be co-transduced with genes encoding proteins that target cells to specific locations. Here, we present a protocol to transduce primary peripheral blood mononuclear cells (PBMCs) with genes encoding a virus-specific CAR and the B cell follicle homing molecule chemokine receptor type 5 (CXCR5). This procedure takes nine days and results in transduced T cell populations that maintain a central memory phenotype. Maintenance of a central memory or less differentiated phenotype has been shown to associate with persistence of cells post-infusion. Furthermore, cells produced with this method show high levels of viability, high levels of co-expression of the two transduced genes, and large enough quantities of cells for immunotherapeutic infusion. This nine-day protocol may be broadly used for CAR-T cell and other T cell immunotherapy approaches. The methods described here are based on studies presented in our previous publications.


Assuntos
Receptores de Antígenos de Linfócitos T/imunologia , Receptores de Antígenos Quiméricos/imunologia , Linfócitos T/imunologia , Técnicas de Cultura de Células , Sobrevivência Celular , Imunoterapia Adotiva , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Fenótipo , Receptores de Antígenos de Linfócitos T/metabolismo , Receptores CXCR5/genética , Receptores CXCR5/metabolismo , Receptores de Antígenos Quiméricos/genética , Receptores de Antígenos Quiméricos/metabolismo , Linfócitos T/metabolismo , Transdução Genética
18.
Mol Carcinog ; 59(7): 724-735, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32333465

RESUMO

The immunosuppressive microenvironment in solid tumors is thought to form a barrier to the entry and efficacy of cell-based therapies such as chimeric antigen receptor (CAR) T cells. Combining CAR T cell therapy with checkpoint inhibitors has been demonstrated to oppose immune escape mechanisms in solid tumors and augment antitumor efficacy. We evaluated PD-1/PD-L1 signaling capacity and the impact of an inhibitor of this checkpoint axis in an in vitro system for cancer cell challenge, the coculture of L1CAM-specific CAR T cells with neuroblastoma cell lines. Fluorescence-activated cell sorting-based analyses and luciferase reporter assays were used to assess PD-1/PD-L1 expression on CAR T and tumor cells as well as CAR T cell ability to kill neuroblastoma cells. Coculturing neuroblastoma cell lines with L1CAM-CAR T cells upregulated PD-L1 expression on neuroblastoma cells, confirming adaptive immune resistance. Exposure to neuroblastoma cells also upregulated the expression of the PD-1/PD-L1 axis in CAR T cells. The checkpoint inhibitor, nivolumab, enhanced L1CAM-CAR T cell-directed killing. However, nivolumab-enhanced L1CAM-CAR T cell killing did not strictly correlate with PD-L1 expression on neuroblastoma cells. In fact, checkpoint inhibitor success relied on strong PD-1/PD-L1 axis expression in the CAR T cells, which in turn depended on costimulatory domains within the CAR construct, and more importantly, on the subset of T cells selected for CAR T cell generation. Thus, T cell subset selection for CAR T cell generation and CAR T cell prescreening for PD-1/PD-L1 expression could help determine when combination therapy with checkpoint inhibitors could improve treatment efficacy.


Assuntos
Receptores de Antígenos de Linfócitos T/metabolismo , Linfócitos T/metabolismo , Antígeno B7-H1/metabolismo , Linhagem Celular Tumoral , Humanos , Neuroblastoma/metabolismo , Fenótipo , Receptor de Morte Celular Programada 1/metabolismo , Microambiente Tumoral/fisiologia
19.
Proc Natl Acad Sci U S A ; 117(11): 6042-6046, 2020 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-32111690

RESUMO

Induction of longstanding immunologic tolerance is essential for survival of transplanted organs and tissues. Despite recent advances in immunosuppression protocols, allograft damage inflicted by antibody specific for donor organs continues to represent a major obstacle to graft survival. Here we report that activation of regulatory CD8 T cells (CD8 Treg) that recognize the Qa-1 class Ib major histocompatibility complex (MHC), a mouse homolog of human leukocyte antigen-E (HLA-E), inhibits antibody-mediated immune rejection of heart allografts. We analyzed this response using a mouse model that harbors a point mutation in the class Ib MHC molecule Qa-1, which disrupts Qa-1 binding to the T cell receptor (TCR)-CD8 complex and impairs the CD8 Treg response. Despite administration of cytotoxic T lymphocyte antigen 4 (CTLA-4) immunoglobulin (Ig), Qa-1 mutant mice developed robust donor-specific antibody responses and accelerated heart graft rejection. We show that these allo-antibody responses reflect diminished Qa-1-restricted CD8 Treg-mediated suppression of host follicular helper T cell-dependent antibody production. These findings underscore the critical contribution of this Qa-1/HLA-E-dependent regulatory pathway to maintenance of transplanted organs and suggest therapeutic approaches to ameliorate allograft rejection.


Assuntos
Rejeição de Enxerto/imunologia , Transplante de Coração/efeitos adversos , Antígenos de Histocompatibilidade Classe I/imunologia , Linfócitos T Auxiliares-Indutores/metabolismo , Linfócitos T Reguladores/imunologia , Aloenxertos/imunologia , Aloenxertos/metabolismo , Animais , Modelos Animais de Doenças , Rejeição de Enxerto/sangue , Rejeição de Enxerto/genética , Sobrevivência de Enxerto/imunologia , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/metabolismo , Humanos , Tolerância Imunológica , Isoanticorpos/imunologia , Isoanticorpos/metabolismo , Isoantígenos/imunologia , Isoantígenos/metabolismo , Camundongos , Miocárdio/imunologia , Miocárdio/metabolismo , Mutação Puntual , Receptores de Antígenos de Linfócitos T/imunologia , Receptores de Antígenos de Linfócitos T/metabolismo , Linfócitos T Auxiliares-Indutores/imunologia , Transplante Homólogo/efeitos adversos
20.
PLoS One ; 15(3): e0229569, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32134923

RESUMO

We previously showed, in a pilot study with publicly available data, that T cell receptor (TCR) repertoires from tumor infiltrating lymphocytes (TILs) could be distinguished from adjacent healthy tissue repertoires by the presence of TCRs bearing specific, biophysicochemical motifs in their antigen binding regions. We hypothesized that such motifs might allow development of a novel approach to cancer detection. The motifs were cancer specific and achieved high classification accuracy: we found distinct motifs for breast versus colorectal cancer-associated repertoires, and the colorectal cancer motif achieved 93% accuracy, while the breast cancer motif achieved 94% accuracy. In the current study, we sought to determine whether such motifs exist for ovarian cancer, a cancer type for which detection methods are urgently needed. We made two significant advances over the prior work. First, the prior study used patient-matched TILs and healthy repertoires, collecting healthy tissue adjacent to the tumors. The current study collected TILs from patients with high-grade serous ovarian carcinoma (HGSOC) and healthy ovary repertoires from cancer-free women undergoing hysterectomy/salpingo-oophorectomy for benign disease. Thus, the classification task is distinguishing women with cancer from women without cancer. Second, in the prior study, classification accuracy was measured by patient-hold-out cross-validation on the training data. In the current study, classification accuracy was additionally assessed on an independent cohort not used during model development to establish the generalizability of the motif to unseen data. Classification accuracy was 95% by patient-hold-out cross-validation on the training set and 80% when the model was applied to the blinded test set. The results on the blinded test set demonstrate a biophysicochemical TCR motif found overwhelmingly in women with HGSOC but rarely in women with healthy ovaries, strengthening the proposal that cancer detection approaches might benefit from incorporation of TCR motif-based biomarkers. Furthermore, these results call for studies on large cohorts to establish higher classification accuracies, as well as for studies in other cancer types.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias Ovarianas/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Carcinoma Epitelial do Ovário/metabolismo , Estudos de Coortes , Cistadenocarcinoma Seroso/metabolismo , Feminino , Humanos , Linfócitos do Interstício Tumoral/metabolismo , Pessoa de Meia-Idade , Ovário/metabolismo , Projetos Piloto
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