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1.
Cancer Immunol Immunother ; 68(12): 1979-1993, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31686124

RESUMO

5T4 (trophoblast glycoprotein, TPBG) is a transmembrane tumor antigen expressed on more than 90% of primary renal cell carcinomas (RCC) and a wide range of human carcinomas but not on most somatic adult tissues. The favorable expression pattern has encouraged the development and clinical testing of 5T4-targeted antibody and vaccine therapies. 5T4 also represents a compelling and unexplored target for T-cell receptor (TCR)-engineered T-cell therapy. Our group has previously isolated high-avidity CD8+ T-cell clones specific for an HLA-A2-restricted 5T4 epitope (residues 17-25; 5T4p17). In this report, targeted single-cell RNA sequencing was performed on 5T4p17-specific T-cell clones to sequence the highly variable complementarity-determining region 3 (CDR3) of T-cell receptor α chain (TRA) and ß chain (TRB) genes. Full-length TRA and TRB sequences were cloned into lentiviral vectors and transduced into CD8+ T-cells from healthy donors. Redirected effector T-cell function against 5T4p17 was measured by cytotoxicity and cytokine release assays. Seven unique TRA-TRB pairs were identified. All seven TCRs exhibited high expression on CD8+ T-cells with transduction efficiencies from 59 to 89%. TCR-transduced CD8+ T-cells demonstrated redirected cytotoxicity and cytokine release in response to 5T4p17 on target-cells and killed 5T4+/HLA-A2+ kidney-, breast-, and colorectal-tumor cell lines as well as primary RCC tumor cells in vitro. TCR-transduced CD8+ T-cells also detected presentation of 5T4p17 in TAP1/2-deficient T2 target-cells. TCR-transduced T-cells redirected to recognize the 5T4p17 epitope from a broadly shared tumor antigen are of interest for future testing as a cellular immunotherapy strategy for HLA-A2+ subjects with 5T4+ tumors.


Assuntos
Linfócitos T CD8-Positivos/fisiologia , Vacinas Anticâncer/imunologia , Carcinoma de Células Renais/terapia , Epitopos de Linfócito T/metabolismo , Imunoterapia Adotiva/métodos , Neoplasias Renais/terapia , Glicoproteínas de Membrana/metabolismo , Linfócitos T CD8-Positivos/transplante , Carcinoma de Células Renais/imunologia , Células Clonais , Citotoxicidade Imunológica , Epitopos de Linfócito T/imunologia , Antígeno HLA-A2/metabolismo , Humanos , Neoplasias Renais/imunologia , Glicoproteínas de Membrana/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/genética
2.
Mol Immunol ; 116: 167-173, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31698163

RESUMO

Primary biliary cholangitis (PBC) is considered as a model of organ-specific autoimmune disease based on the serological findings of anti-mitochondrial antibodies (AMA), infiltrates of T cells, and selective destruction of epithelial cells in the liver. T-cell-mediated autoimmune mechanisms are considered to be involved in the pathogenesis of primary biliary cholangitis (PBC). In this context, we used a combination of multiplex-PCR, Illumina sequencing and IMGT/HighV-QUEST for a standardized analysis of the T cell receptor ß-chain (TCRß) repertoire of CD4+naive T cells in PBC patients compared with healthy volunteers. Nonfunctional TCRs were used to study the pre-selection TCR repertoire, as they are not subject to functional selection (positive and negative selection). Functional TCRs were used to study the post-selection TCR repertoire. The results showed that there was not significant difference between PBC patients and healthy volunteers in TCRß diversity, CDR3 length distributions, degree of sequence sharing, and usage frequency of TRBV and TRBJ segments, no matter in Pre-selection or Post-selection repertoires. In conclusion, early events in thymic T cell development and repertoire generation are not abnormality in PBC patients. The breakdown of self-tolerance to autoantigen may be derived from other immunological dysregulation or environmental agents.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Cirrose Hepática Biliar/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Adulto , Idoso , Autoantígenos/imunologia , Doenças Autoimunes/imunologia , Células Epiteliais/imunologia , Feminino , Voluntários Saudáveis , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Fígado/imunologia , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Multiplex/métodos
3.
Mol Immunol ; 116: 174-179, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31704500

RESUMO

We considered the possibility that the greater the distance between an immune receptor V and J, the more likely the V usage. Such a hypothesis is supported by results from mouse experiments. And, such a hypothesis is consistent with the fundamental nature of recombination and genomic distance: the further the distance, the greater the chance of a DNA break. Thus, we exploited the vast dataset of V and J recombination reads available for the human TRA gene, particularly from cancer and blood specimens, to assess the frequency of TRAV usage with respect to distance from the TRAJ cluster. Results indicated that, indeed, over the entire TRAV cluster, there is a greater chance of V usage the further the distance from the J cluster. These results do not address causation, and are not consistent for certain individual V gene segments, but the results do indicate that overall, the larger the distance between the V and J gene segment cluster, the more likely the appearance of at least a subset of TRAV segments, particularly among tumor infiltrating lymphocytes. With a similar approach, the distal TRAV gene segments were also found to be more commonly associated with a subset of distal TRAJ segments. These results have implications for restrictions on the apparent TRA repertoire in disease settings.


Assuntos
Família Multigênica/genética , Neoplasias/genética , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Humanos , Linfócitos do Interstício Tumoral/imunologia , Família Multigênica/imunologia , Neoplasias/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia
4.
Anticancer Res ; 39(11): 5911-5918, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31704815

RESUMO

BACKGROUND/AIM: Double-negative T (DNT) cells are phenotypically CD3+CD4-CD8-T cells. This study aimed to investigate the anti-cancer activity of DNT cells against pancreatic cancer cells. MATERIALS AND METHODS: DNT cells were isolated from human peripheral blood. The effect of DNT cells on proliferation and invasion of the human pancreatic cell line Panc-1 was assessed. Expression of Nrf2 and Fas in Panc-1 cells co-cultured with DNT cells was analyzed with RT-PCR. The supernatants of Panc-1 and DNT co-cultures were analyzed with ELISA for IFN-r and FasL levels. RESULTS: The isolated DNT cell phenotype was CD4-CD8-CD56- CD3+TCR (T cell receptor) α/ß+ T cells with more than 90% purity. Panc-1 cell proliferation was significantly inhibited by co-culture with DNT cells. Panc-1 cells co-cultured with DNT cells showed significantly reduced cell invasion. Panc-1 cells co-cultured with DNT cells showed increased Nrf2 and Fas mRNA expression. Increased INF-r and FasL levels were detected in the supernatants of co-cultures of DNT and pancreatic cells. CONCLUSION: DNT cells inhibited proliferation and invasion of human pancreatic cancer cells. The INF-r, Fas/FasL pathway and Nrf2 may be involved in the anti-cancer effect of DNT cells against human pancreatic cancer.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Técnicas de Cocultura/métodos , Ativação Linfocitária/imunologia , Neoplasias Pancreáticas/prevenção & controle , Apoptose , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Proliferação de Células , Proteína Ligante Fas/metabolismo , Humanos , Fator 2 Relacionado a NF-E2/metabolismo , Neoplasias Pancreáticas/imunologia , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Receptores de Antígenos de Linfócitos T alfa-beta/metabolismo , Receptores de Interferon/metabolismo , Células Tumorais Cultivadas , Receptor fas/metabolismo
5.
Cancer Sci ; 110(10): 3038-3048, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31385405

RESUMO

Retroperitoneal liposarcoma (RLPS) is one of the most common subtypes of retroperitoneal soft tissue sarcomas and lacks effective treatment. This study aimed to provide a thorough profile of immune characteristics of RLPS. This study included 56 RLPS patients. Multisite tumor tissues were collected from 16 patients. Immunohistochemistry was carried out to identify CD4+ , CD8+ , FoxP3+ , CD20+ , or programmed cell death-1 (PD-1)+ tumor infiltrating lymphocytes (TILs) and  Programmed cell death ligand-1 (PD-L1) expression in tumor tissues. Ultradeep sequencing of T-cell receptor (TCR) ß-chain gene was carried out in 42 tumor samples as well as peripheral blood samples collected from 6 patients. In RLPS, TILs were distributed in 3 patterns and T cells were more prevalent than B cells. Generally, the proportion of TILs decreased and PD-L1 expression increased with tumor progression. Patients with higher PD-1/PD-L1 expression tended to have poorer prognosis, whereas patients with tertiary lymphoid structure tended to have a favorable disease-free survival. Although T-cell clones in tumors were quite different from those in peripheral blood, TCR sequencing showed low TCR repertoire reads as well as polyclonal status within tumors, which indicated limited T cell response in the tumors. Both TILs distribution and TCR repertoires suggested spatial immune heterogeneity in RLPS. Our research described the immune landscape of RLPS, and suggested RLPS might be a kind of tumor with low T cell infiltration as well as great immune heterogeneity. Therefore, strategies that can facilitate lymphocytic infiltration and immune reactivity need to be developed in the future to improve the efficacy of immunotherapy.


Assuntos
Antígeno B7-H1/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Lipossarcoma/imunologia , Linfócitos do Interstício Tumoral/imunologia , Receptor de Morte Celular Programada 1/metabolismo , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Neoplasias Retroperitoneais/imunologia , Adulto , Idoso , Linfócitos B/imunologia , Intervalo Livre de Doença , Regulação para Baixo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Lipossarcoma/genética , Lipossarcoma/mortalidade , Masculino , Pessoa de Meia-Idade , Prognóstico , Neoplasias Retroperitoneais/genética , Neoplasias Retroperitoneais/mortalidade , Análise de Sequência de DNA , Linfócitos T/imunologia , Regulação para Cima
6.
Nat Commun ; 10(1): 3569, 2019 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-31395875

RESUMO

Drug hypersensitivity such as severe cutaneous adverse reactions (SCAR), including Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN), could be life-threatening. Here, we enroll SCAR patients to investigate the T cell receptor (TCR) repertoire by next-generation sequencing. A public αßTCR is identified from the cytotoxic T lymphocytes of patients with carbamazepine-SJS/TEN, with its expression showing drug/phenotype-specificity and an bias for HLA-B*15:02. This public αßTCR has binding affinity for carbamazepine and its structural analogs, thereby mediating the immune response. Adoptive transfer of T cell expressing this public αßTCR to HLA-B*15:02 transgenic mice receiving oral administration of carbamazepine induces multi-organ injuries and symptoms mimicking SCAR, including hair loss, erythema, increase of inflammatory lymphocytes in the skin and blood, and liver and kidney dysfunction. Our results not only demonstrate an essential role of TCR in the immune synapse mediating SCAR, but also implicate potential clinical applications and development of therapeutics.


Assuntos
Carbamazepina/efeitos adversos , Complexo Receptor-CD3 de Antígeno de Linfócitos T/metabolismo , Receptores de Antígenos de Linfócitos T alfa-beta/metabolismo , Síndrome de Stevens-Johnson/imunologia , Linfócitos T Citotóxicos/imunologia , Transferência Adotiva , Adulto , Idoso , Animais , Modelos Animais de Doenças , Feminino , Antígeno HLA-B15/genética , Antígeno HLA-B15/imunologia , Humanos , Masculino , Camundongos Transgênicos , Pessoa de Meia-Idade , Complexo Receptor-CD3 de Antígeno de Linfócitos T/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Índice de Gravidade de Doença , Pele/imunologia , Pele/patologia , Síndrome de Stevens-Johnson/diagnóstico , Síndrome de Stevens-Johnson/patologia , Linfócitos T Citotóxicos/metabolismo , Linfócitos T Citotóxicos/transplante
7.
Immunogenetics ; 71(8-9): 513-518, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31418051

RESUMO

Demonstration that immature CD4 + 8+ thymocytes contain T cell precursors that are subjected to positive and negative selection was the major step towards understanding how the adaptive immune system acquires the ability to distinguish foreign or abnormal (mutated or infected) self-cells from normal (healthy) cells. In the present review, the roles of TCR, CD4, CD8, and MHC molecules in intrathymic selection and some of the crucial experiments that contributed to the solution of the great immunological puzzle of self/nonself discrimination are described in an historical perspective. Recently, these experiments were highlighted by the immunological community by awarding the 2016 Novartis Prize for Immunology to Philippa Marrack, John Kappler, and Harald von Boehmer.


Assuntos
Células Apresentadoras de Antígenos/imunologia , Doenças Autoimunes/imunologia , Sistema Imunitário/imunologia , Tolerância a Antígenos Próprios , Subpopulações de Linfócitos T/imunologia , Timo/imunologia , Animais , Humanos , Complexo Principal de Histocompatibilidade/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Timo/citologia
8.
Nat Immunol ; 20(9): 1244-1255, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31431722

RESUMO

Mucosal-associated invariant T cells (MAIT cells) recognize the microbial metabolite 5-(2-oxopropylideneamino)-6-D-ribitylaminouracil (5-OP-RU) presented by the MHC class Ib molecule, MR1. MAIT cells acquire effector functions during thymic development, but the mechanisms involved are unclear. Here we used single-cell RNA-sequencing to characterize the developmental path of 5-OP-RU-specific thymocytes. In addition to the known MAIT1 and MAIT17 effector subsets selected on bone-marrow-derived hematopoietic cells, we identified 5-OP-RU-specific thymocytes that were selected on thymic epithelial cells and differentiated into CD44- naive T cells. MAIT cell positive selection required signaling through the adapter, SAP, that controlled the expression of the transcription factor, ZBTB16. Pseudotemporal ordering of single cells revealed transcriptional trajectories of 5-OP-RU-specific thymocytes selected on either thymic epithelial cells or hematopoietic cells. The resulting model illustrates T cell lineage decisions.


Assuntos
Linhagem da Célula/imunologia , Células T Invariáveis Associadas à Mucosa/citologia , Células T Invariáveis Associadas à Mucosa/imunologia , Ribitol/análogos & derivados , Timócitos/citologia , Timócitos/imunologia , Uracila/análogos & derivados , Animais , Sequência de Bases , Diferenciação Celular/genética , Diferenciação Celular/imunologia , Antígenos de Histocompatibilidade Classe I/metabolismo , Receptores de Hialuronatos/metabolismo , Ativação Linfocitária/imunologia , Camundongos , Camundongos Knockout , Antígenos de Histocompatibilidade Menor/metabolismo , Proteína com Dedos de Zinco da Leucemia Promielocítica/biossíntese , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Ribitol/imunologia , Análise de Sequência de RNA , Família de Moléculas de Sinalização da Ativação Linfocitária/metabolismo , Timo/citologia , Timo/imunologia , Uracila/imunologia
9.
Int J Mol Sci ; 20(14)2019 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-31373285

RESUMO

Over the last decades, there has been an impressive progress in our understanding of coeliac disease pathogenesis and it has become clear that the disorder is the final result of complex interactions of environmental, genetic, and immunological factors. Coeliac disease is now considered a prototype of T-cell-mediated disease characterized by loss of tolerance to dietary gluten and the targeted killing of enterocytes by T-cell receptor αß intraepithelial lymphocytes. Accumulating evidence, however, indicates that the induction of a gluten-specific T helper-1 response must be preceded by the activation of the innate immune system. Mast cells are key players of the innate immune response and contribute to the pathogenesis of a multitude of diseases. Here, we review the results of studies aimed at investigating the role of mast cells in the pathogenesis of coeliac disease, showing that these cells increase in number during the progression of the disease and contribute to define a pro-inflammatory microenvironment.


Assuntos
Doença Celíaca/imunologia , Doença Celíaca/patologia , Gliadina/imunologia , Mastócitos/imunologia , Linfócitos T/imunologia , Doença Celíaca/genética , Enterócitos/metabolismo , Cadeias alfa de HLA-DQ/genética , Cadeias alfa de HLA-DQ/imunologia , Humanos , Tolerância Imunológica/imunologia , Imunidade Inata/imunologia , Mastócitos/patologia , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia
10.
Nat Commun ; 10(1): 3353, 2019 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-31350389

RESUMO

The diverse repertoire of T cell receptors (TCR) and immunoglobulins is generated through the somatic rearrangement of respective V, D and J gene segments, termed V(D)J recombination, during early T or B cell development. However, epigenetic regulation of V(D)J recombination is still not fully understood. Here we show that the deficiency of Setd2, a histone methyltransferase that catalyzes lysine 36 trimethylation on histone 3 (H3K36me3) in mice, causes a severe developmental block of thymocytes at the CD4-CD8- DN3 stage. While H3K36me3 is normally enriched at the TCRß locus, Setd2 deficiency reduces TCRß H3K36me3 and suppresses TCRß V(D)J rearrangement by impairing RAG1 binding to TCRß loci and the DNA double-strand break repair. Similarly, Setd2 ablation also impairs immunoglobulin V(D)J rearrangement to induce B cell development block at the pro-B stage. Lastly, SETD2 is frequently mutated in patients with primary immunodeficiency. Our study thus demonstrates that Setd2 is required for optimal V(D)J recombination and normal lymphocyte development.


Assuntos
Histona-Lisina N-Metiltransferase/metabolismo , Recombinação V(D)J , Motivos de Aminoácidos , Animais , Linfócitos B/citologia , Linfócitos B/enzimologia , Diferenciação Celular , Pré-Escolar , Epigênese Genética , Histona-Lisina N-Metiltransferase/genética , Histonas/química , Histonas/metabolismo , Humanos , Lactente , Lisina/genética , Lisina/metabolismo , Masculino , Metilação , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mutação , /genética , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Receptores de Antígenos de Linfócitos T alfa-beta/metabolismo , Linfócitos T/citologia
11.
Scand J Immunol ; 90(5): e12806, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31276223

RESUMO

The Standard model of T cell recognition asserts that T cell receptor (TCR) specificities are positively and negatively selected during ontogeny in the thymus and that peripheral T cell repertoire has mild self-major histocompatibility complex (MHC) reactivity, known as MHC restriction of foreign antigen. Thus, the TCR must bind both a restrictive molecule (MHC allele) and a peptide reclining in its groove (pMHC ligand) in order to transmit signal into a T cell. The Standard and Cohn's Tritope models suggest contradictory roles for complementarity-determining regions (CDRs) of the TCRs. Here, I discuss both concepts and propose a different solution to ontogenetic mechanism for TCR-MHC-conserved interaction. I suggest that double (CD4+ CD8+ )-positive (DP) developing thymocytes compete with their αßTCRs for binding to self-pMHC on cortical thymic epithelial cells (cTECs) that present a selected set of tissue-restricted antigens. The competition between DPs involves TCR editing and secondary rearrangements, similar to germinal-centre B cell somatic hypermutation. These processes would generate cells with higher TCR affinity for self-pMHC, facilitating sufficiently long binding to cTECs to become thymic T regulatory cells (tTregs). Furthermore, CD4+ Foxp3+ tTregs can be generated by mTECs via Aire-dependent and Aire-independent pathways, and additionally on thymic bone marrow-derived APCs including thymic Aire-expressing B cells. Thymic Tregs differ from the induced peripheral Tregs, which comprise the negative feedback loop to restrain immune responses. The implication of thymocytes' competition for the highest binding to self-pMHC is the co-evolution of species-specific αßTCR V regions with MHC alleles.


Assuntos
Regiões Determinantes de Complementaridade/imunologia , Complexo Principal de Histocompatibilidade/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Linfócitos T Reguladores/imunologia , Humanos , Ativação Linfocitária/imunologia , Especificidade do Receptor de Antígeno de Linfócitos T/imunologia , Timo/imunologia , Fatores de Transcrição/metabolismo
12.
Braz J Infect Dis ; 23(3): 151-159, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31271732

RESUMO

BACKGROUND: HIV infection harms adaptive cellular immunity mechanisms. Long-term virological control by combined antiretroviral therapy (cART) reduces the risk of mycobacterial infections. Thus, we aimed to study cellular responses to mycobacterial antigens in 20 HIV-infected adolescents with at least one year of virological control (HIV-RNA <40 copies/mL) and 20 healthy adolescents. METHODS: We evaluated CD8 and γδ T-cell degranulation by measurement of CD107a membrane expression after stimulation with lysates from BCG (10 µg/mL) and H37RA Mycobacterium tuberculosis (Mtb, 10 µg/mL). Immune activation and antigen-presenting ability were also assessed by determination of HLA-DR, CD80, and CD86 markers. RESULTS: TCR γδ T-cell CD107a expression was similar between groups in response to mycobacterial antigens, and lower in the HIV-infected group in response to mitogen. Higher baseline HLA-DR expression and lower mycobacterial-stimulated expression was found within the HIV-infected group. CONCLUSIONS: Similar degranulation in stimulated CD8+ and TCR γδ T-cells from HIV-infected adolescents, when compared to healthy controls suggests long-term immunological preservation with immune reconstitution under successful cART. However, differences in HLA-DR expression may represent ongoing inflammation and lower specific responses in HIV-infected youth. These features may be relevant in the context of the precocity and severity of vertically acquired HIV infection.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/imunologia , Fármacos Anti-HIV/uso terapêutico , Antígenos de Bactérias/imunologia , Linfócitos T CD8-Positivos/imunologia , Mycobacterium tuberculosis/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Tuberculose/imunologia , Apresentação do Antígeno/imunologia , Antígenos de Bactérias/efeitos dos fármacos , Biomarcadores/sangue , Estudos Transversais , Feminino , Humanos , Imunofenotipagem , Transmissão Vertical de Doença Infecciosa , Masculino , Estudos Prospectivos , Adulto Jovem
13.
Immunohorizons ; 3(1): 1-12, 2019 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-31356172

RESUMO

Respiratory syncytial virus (RSV) is the most common cause of lower respiratory tract infection and hospitalization in infants. It is well established that both CD4+ and CD8+ T cells are critical for mediating viral clearance but also contribute to the induction of immunopathology following RSV infection. C57BL/6 mice are often used to study T cell responses following RSV infection given the wide variety of genetically modified animals available. To date, few RSV-derived CD4+ and CD8+ T cell epitopes have been identified in C57BL/6 mice. Using an overlapping peptide library spanning the entire RSV proteome, intracellular cytokine staining for IFN-γ was performed to identify novel CD4+ and CD8+ T cell epitopes in C57BL/6 mice. We identified two novel CD4+ T cell epitopes and three novel CD8+ T cell epitopes located within multiple RSV proteins. Additionally, we characterized the newly described T cell epitopes by determining their TCR Vß expression profiles and MHC restriction. Overall, the novel RSV-derived CD4+ and CD8+ T cell epitopes identified in C57BL/6 mice will aid in future studies of RSV-specific T cell responses.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Epitopos de Linfócito T/metabolismo , Infecções por Vírus Respiratório Sincicial/patologia , Vírus Sincicial Respiratório Humano/metabolismo , Animais , Linhagem Celular Tumoral , Feminino , Antígenos de Histocompatibilidade Classe I/imunologia , Interferon gama/metabolismo , Pulmão/patologia , Camundongos , Camundongos Endogâmicos C57BL , Biblioteca de Peptídeos , Receptores de Antígenos de Linfócitos T alfa-beta/metabolismo , Proteínas Virais/metabolismo
14.
Biochem Soc Trans ; 47(4): 1077-1089, 2019 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-31249100

RESUMO

In T cell development, a pivotal decision-making stage, termed ß-selection, integrates a TCRß checkpoint to coordinate survival, proliferation and differentiation to an αß T cell. Here, we review how transcriptional regulation coordinates fate determination in early T cell development to enable ß-selection. Errors in this transcription control can trigger T cell acute lymphoblastic leukaemia. We describe how the ß-selection checkpoint goes awry in leukaemic transformation.


Assuntos
Carcinogênese , Sobrevivência Celular , Regulação da Expressão Gênica , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia , Linfócitos T/citologia , Transcrição Genética , Ativação Metabólica , Animais , Diferenciação Celular , Proliferação de Células , Humanos , Leucemia-Linfoma Linfoblástico de Células T Precursoras/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Linfócitos T/imunologia
15.
Nat Immunol ; 20(8): 1046-1058, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31209405

RESUMO

The neonatal thymus generates Foxp3+ regulatory T (tTreg) cells that are critical in controlling immune homeostasis and preventing multiorgan autoimmunity. The role of antigen specificity on neonatal tTreg cell selection is unresolved. Here we identify 17 self-peptides recognized by neonatal tTreg cells, and reveal ligand specificity patterns that include self-antigens presented in an age- and inflammation-dependent manner. Fate-mapping studies of neonatal peptidyl arginine deiminase type IV (Padi4)-specific thymocytes reveal disparate fate choices. Neonatal thymocytes expressing T cell receptors that engage IAb-Padi4 with moderate dwell times within a conventional docking orientation are exported as tTreg cells. In contrast, Padi4-specific T cell receptors with short dwell times are expressed on CD4+ T cells, while long dwell times induce negative selection. Temporally, Padi4-specific thymocytes are subject to a developmental stage-specific change in negative selection, which precludes tTreg cell development. Thus, a temporal switch in negative selection and ligand binding kinetics constrains the neonatal tTreg selection window.


Assuntos
Autoantígenos/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Tolerância a Antígenos Próprios/imunologia , Linfócitos T Reguladores/citologia , Animais , Autoimunidade/imunologia , Diferenciação Celular/imunologia , Linhagem Celular , Feminino , Fatores de Transcrição Forkhead/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Desiminases de Arginina em Proteínas/metabolismo , Linfócitos T Reguladores/imunologia , Timo/citologia
16.
Environ Toxicol Pharmacol ; 71: 103211, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31212134

RESUMO

We exploratively characterized T cell receptor (TCR) repertoires from occupational medicamentosa-like dermatitis due to trichloroethylene (OMDT) patients to better understand the underlying pathological mechanism. We used a combination of multiplex-PCR, Illumina sequencing and IMGT/High V-QUEST to analyze the characteristics and polymorphisms of the TCR ß-chain complementarity-determining region 3 (CDR3) gene in 10 OMDT cases and 10 trichloroethylene-exposed healthy tolerant controls. Compared with the tolerant controls, OMDT cases showed no significant difference in TCR repertoire diversity including repertoire breadth, highly expanded clone, and CDR3 length distribution. However, we observed several differences in TRBV/TRBJ usage and combination between the two groups, as well as some shared and unique T cell clones in the cases. The pilot study delineated some features of TCR repertoire in OMDT patients that warrant further investigation.


Assuntos
Regiões Determinantes de Complementaridade/sangue , Erupção por Droga/sangue , Doenças Profissionais/sangue , Exposição Ocupacional/análise , Receptores de Antígenos de Linfócitos T alfa-beta/sangue , Tricloroetileno/toxicidade , Adulto , Estudos de Casos e Controles , Regiões Determinantes de Complementaridade/genética , Erupção por Droga/genética , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Exposição Ocupacional/efeitos adversos , Projetos Piloto , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Linfócitos T/efeitos dos fármacos
17.
Immunology ; 157(4): 322-330, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31206171

RESUMO

Primary and chronic human immunodeficiency virus (HIV) infection alters γδ T-cell features. However, there is no evidence about early combined antiretroviral therapy (cART) and γδ T-cell dynamics. In the present study, HIV-positive individuals were divided into those with early primary infection (EPI) and those with late primary infection (LPI). The analysis of γδ T cells was performed by flow cytometry before and after therapy. Polyfunctional profile was assessed after in vitro peripheral blood mononuclear cell (PBMC) exposure to specific antigens. The results show that primary infection induced an expansion of Vδ1 T cells in LPI. Before treatment, a massive activation of γδ T-cell subsets was observed in both groups of patients, that correlated with disease progression and was significantly reduced after cART introduction. Despite this, CD107A-expressing Vδ1 T cells in both groups were significantly fewer than in healthy donors, but were restored by therapy introduction. Polyfunctional analysis of Vδ1 T cells from HIV-positive individuals revealed a lower frequency of CD107A+  CCL-4+ Vδ1 T-cell subsets than healthy donors that persists after therapy. Functional profile of Vδ2 was similar to that in healthy donors before therapy but, at 6 months, a lower frequency of CD107A, interferon-γ- or tumor necrosis factor-α-producing Vδ2 T cells was observed in the EPI group. Finally, individuals with LPI showed a lower frequency of quadruple-functional Vδ2 T-cell subset. In conclusion, during primary HIV infection, the baseline Vδ1 T-cell activation is correlated with immune reconstitution potential. Moreover, an altered γδ polyfunctional profile occurred, persisting after cART. Further studies are needed to understand whether a longer treatment of primary infection may increase γδ T-cell functionality.


Assuntos
Antirretrovirais/administração & dosagem , Infecções por HIV/imunologia , HIV-1/imunologia , Ativação Linfocitária/efeitos dos fármacos , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Linfócitos T/imunologia , Adulto , Quimiocina CCL4/imunologia , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/patologia , Humanos , Interferon gama/imunologia , Proteína 1 de Membrana Associada ao Lisossomo/imunologia , Masculino , Pessoa de Meia-Idade , Linfócitos T/patologia , Fator de Necrose Tumoral alfa/imunologia
18.
PLoS Biol ; 17(5): e3000262, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31071093

RESUMO

Intestinal intraepithelial lymphocytes (IELs) expressing CD8αα on αß T cells (TCRαß+CD8αα+ IELs) have suppressive capabilities in enterocolitis, but the mechanism that maintains homeostasis and cell number is not fully understood. Here, we demonstrated that the number of TCRαß+CD8αα+ IELs was severely reduced in mice lacking recombination signal binding protein for immunoglobulin kappa J region (Rbpj) or Notch1 and Notch2 in T cells. Rbpj-deficient TCRαß+CD8αα+ IELs expressed low levels of Atp8a2, which encodes a protein with flippase activity that regulates phospholipid asymmetry of plasma membrane such as flipping phosphatidylserine in the inner leaflet of plasma membrane. Rbpj-deficient TCRαß+CD8αα+ IELs cannot maintain phosphatidylserine in the inner leaflet of the plasma membrane. Furthermore, depletion of intestinal macrophages restored TCRαß+CD8αα+ IELs in Rbpj-deficient mice, suggesting that exposure of phosphatidylserine on the plasma membrane in Rbpj-deficient TCRαß+CD8αα+ IELs acts as an "eat-me" signal. Together, these results revealed that Notch-Atp8a2 is a fundamental regulator for IELs and highlighted that membrane phospholipid asymmetry controlled by Notch-mediated flippase expression is a critical determinant in setting or balancing the number of TCRαß+CD8αα+ IELs.


Assuntos
Linfócitos T CD8-Positivos/metabolismo , Linfócitos Intraepiteliais/metabolismo , Fosfolipídeos/metabolismo , Receptores de Antígenos de Linfócitos T alfa-beta/metabolismo , Receptores Notch/metabolismo , Adenosina Trifosfatases/metabolismo , Animais , Proteína de Ligação a Sequências Sinal de Recombinação J de Imunoglobina/metabolismo , Macrófagos/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Proteínas de Transferência de Fosfolipídeos/metabolismo
19.
PLoS One ; 14(5): e0216815, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31071196

RESUMO

Using induced pluripotent stem cells (iPSCs) to derive chimeric antigen receptor-modified T (CAR-T) cells has great industrial potential. A previous study used αß T cell-derived CAR-modified iPSCs to produce CAR-T cells. However, these αß T cells are restricted to autologous use and only recognize single cancer antigen. To make CAR-T alternative for allogeneic use, we reprogrammed γδ T cell into iPSCs (γδ T-iPSCs) to circumvent the risk of graft-versus-host disease. To target multiple cancer-associated antigens, we used an "NK cell-promoting" protocol to differentiate γδ T-iPSCs and to induce expression of natural killer receptors (NKRs). Through such two-step strategy, mimetic γδ T cells endowed with an array of NKRs and thus designated as "γδ natural killer T (γδ NKT) cells" were derived. With no/low-level expression of inhibitory killer cell immunoglobulin-like receptors (KIRs) and immune checkpoint receptors, γδ NKT cells may provide a potent "off-the-shelf" cytotoxic cell source to recognize multiple ubiquitous antigens in a broad spectrum of cancers.


Assuntos
Antígenos de Neoplasias/imunologia , Células-Tronco Pluripotentes Induzidas/imunologia , Células T Matadoras Naturais/imunologia , Neoplasias/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Receptores de Antígenos Quiméricos/imunologia , Antígenos de Neoplasias/genética , Células HCT116 , Células Hep G2 , Humanos , Células-Tronco Pluripotentes Induzidas/patologia , Células K562 , Células MCF-7 , Células T Matadoras Naturais/patologia , Neoplasias/genética , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Receptores de Antígenos Quiméricos/genética , Células THP-1
20.
Orphanet J Rare Dis ; 14(1): 97, 2019 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-31053147

RESUMO

BACKGROUND: Mosaic variegated aneuploidy (MVA) syndrome is a chromosomal instability disorder that leads to aneuploidies of different chromosomes in various tissues. Type 1 MVA (MVA1) is caused by mutations in the budding uninhibited by benzimidazoles 1 homolog beta (BUB1B) gene. The main clinical features of MVA1 syndrome are growth and mental retardation, central nervous system anomalies, microcephaly, and predisposition to cancers. There have been no reports of hematopoietic stem cell transplantation (HSCT) in MVA patients. RESULTS: We report an 11-year old boy diagnosed with MVA1 syndrome. The BUB1B gene mutations c.498_505delAAACTTTA and c.1288 + 5G > A were detected using the next generation sequencing (NGS) method. The patient presented with cytopenia soon after birth, but remained stable until 9 years of age, when he developed myelodysplastic syndrome associated with monosomy of chromosome 7. Due to severe dependence on blood transfusions, a TCRαß+/CD19+ depleted HSCT was performed from a matched unrelated donor (MUD) using a treosulfan-based reduced intensity conditioning (RIC) regimen. The engraftment occurred, and no severe toxicity was observed soon after the HSCT, but on day + 47, graft rejection was detected. It was followed by prolonged pancytopenia and sepsis with multi-organ Enterococcus faecium infection, which led to the patient's death on day + 156 after HSCT. CONCLUSIONS: In conclusion, we demonstrate that RIC HSCT with TCRαß+/CD19+ depletion was well tolerated and resulted in complete hematologic recovery in our MVA1 patient, but, unfortunately, it was followed by rapid graft rejection. This fact needs to be taken into consideration for HSCT in other MVA patients.


Assuntos
Antígenos CD19/metabolismo , Transtornos Cromossômicos/metabolismo , Transplante de Células-Tronco Hematopoéticas , Receptores de Antígenos de Linfócitos T alfa-beta/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Instabilidade Cromossômica/genética , Instabilidade Cromossômica/fisiologia , Transtornos Cromossômicos/genética , Transtornos Cromossômicos/terapia , Humanos , Mosaicismo , Mutação/genética , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo
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