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1.
Adv Exp Med Biol ; 1172: 63-78, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31628651

RESUMO

The co-stimulation and co-inhibition signal pathways, immune checkpoints, are among the central mechanisms to regulate the T-cell immunity. Optimal signals involve intricate interactions of numerous ligands and receptors. Manipulation of these signals offers great clinical opportunities and has revolutionized the cancer treatment therapies. The 2018 Nobel Prize in Physiology or Medicine was awarded to James P. Allison and Tasuku Honjo in recognition of their discovery of cancer immunotherapy by inhibition of immune checkpoint molecules. Despite the landmark discovery in cancer immunotherapy, the efforts to harness immunity against cancer are also restricted by the limited knowledge on the co-stimulation and co-inhibition signaling networks. Understanding the structures of these molecules, in particular, tackling the interaction paradigms from the structural perspective, help to provide more accurate insights into the signaling mechanisms, which may further facilitate the development of novel biologics and improve the efficacy of the existing biologics against these targets. Here we review our current understanding on the structures of these co-stimulatory and co-inhibitory molecules. Specifically, we focus on the structural basis of several checkpoint molecules among the CD28-B7 family and discuss the therapeutic drugs against these targets for the treatment of human cancers, autoimmune disorders, and transplantation.


Assuntos
Antígenos CD28 , Linfócitos T , Doenças Autoimunes , Antígenos CD28/química , Antígenos CD28/imunologia , Humanos , Imunoterapia , Neoplasias/terapia , Transplante de Órgãos , Transdução de Sinais/imunologia , Linfócitos T/imunologia
2.
Medicine (Baltimore) ; 98(43): e17608, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31651870

RESUMO

This study aims to investigate the changes of cytokines and the effect of programmed death ligand 1 (PD-L1) signaling pathway on T cell function in patients with immune thrombocytopenic purpura (ITP).Totally, 40 untreated ITP patients were recruited and 30 healthy people were recruited as the healthy control. Then whole blood of ITP patients and healthy control was collected, respectively. The sPD-L1/anti-PD-1 was used to activate or block the programmed death (PD-1)/PD-L1 signaling pathway. The expression of PD-1 and PD-L1 on peripheral blood mononuclear cells (PBMCs) were detected by flow cytometry. PBMCs were treated with cluster of differentiation (CD3), cluster of differentiation 28 (CD28), and phytohaemagglutinin (PHA) for 48 hours. Serum levels of sPD-1, sPD-L1, and cytokines were measured by enzyme-linked immunosorbent assay (ELISA).Compared with the healthy control group, the percentages of PD-1+CD3+CD4+ T cells and PD-L1+HLA-DR+CD11c+ DC cells were increased in ITP patients. The levels of interferon-gamma (IFN-γ), interleukin-17 (IL-17), and sPD-1 in the serum of ITP patients were increased, while IL-4 and transforming growth factor-ß (TGF-ß) were decreased. Additionally, the level of sPD-1 was negatively correlated with the platelet count. Consistently, after treatment with CD3, CD28, and PHA, IFN-γ and IL-17 levels in culture supernatant of PBMCs from ITP patients were significantly higher than those from healthy controls whereas IL-4 and TGF-ß levels were significantly lower. Furthermore, IFN-γ and IL-17 levels secreted by PBMCs from ITP patients decreased after sPD-L1 administration, however, IL-4 and TGF-ß levels were increased. The level of IFN-γ in ITP group remained higher after anti-PD-1 blockage, but the levels of IL-4, TGF-ß, and IL-17 were not significantly influenced.sPD-1 may cause the dysfunction of PD-1/PD-L1 signaling pathway, and its level is related to the severity of ITP patients. Activation of PD-1/PD-L1 with sPD-L1 may restore the imbalance of Th1/Th2 and Treg/Th17 cell subtypes in ITP patients but anti-PD-1 may exacerbate disease by enhancing IFN-γ production.


Assuntos
Antígeno B7-H1/imunologia , Púrpura Trombocitopênica Idiopática/imunologia , Linfócitos T Reguladores/imunologia , Equilíbrio Th1-Th2/fisiologia , Células Th17/imunologia , Adulto , Antígenos CD28/imunologia , Complexo CD3/imunologia , Estudos de Casos e Controles , Citocinas/imunologia , Feminino , Humanos , Interferon gama/metabolismo , Leucócitos Mononucleares , Masculino , Pessoa de Meia-Idade , Fito-Hemaglutininas/imunologia , Receptor de Morte Celular Programada 1/fisiologia , Púrpura Trombocitopênica Idiopática/sangue , Transdução de Sinais/imunologia , Linfócitos T/imunologia , Equilíbrio Th1-Th2/efeitos dos fármacos , Fator de Crescimento Transformador beta/metabolismo
3.
Scand J Immunol ; 90(3): e12802, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31269269

RESUMO

Glucose and nutrient uptake is essential in supporting T cell activation and is increased upon CD3/CD28 stimulation. As T cells from pleural effusions secondary to lung cancer show impaired function, we hypothesized that these cells might have altered expression of nutrient transporters. Here, we analysed by flow cytometry the expression of the transferrin receptor CD71, amino acid transporter CD98 and glucose transporter Glut1 and glucose uptake in pleural effusion-derived T cells from lung cancer patients, after stimulation via CD3/CD28 under normoxia or hypoxia (2% O2 ). We compared the response of T cells from pleural effusions secondary to lung cancer with that of T cells from nonmalignant effusions. In memory T cells from both groups, anti-CD3/CD28-stimulation under normoxia upregulated CD98 and CD71 expression (measured as median fluorescence intensity, MFI) in comparison with anti-CD3-stimulation. Costimulation under hypoxia tended to increase CD98 expression compared to CD3-stimulation in memory T cells from both groups. Remarkably, in the cancer group, memory T cells stimulated via CD3/CD28 under hypoxia failed to increase CD71 and Glut1 expression levels compared to the cells receiving anti-CD3 stimulation, a phenomenon that contrasted with the behaviour of memory T cells from nonmalignant effusions. Consequently, glucose uptake by memory T cells from the cancer group was not increased after CD3/CD28 stimulation under hypoxia, implying that their glycolytic metabolism is defective. As this process is required for inducing an antitumoural response, our study suggests that memory T cells are rendered dysfunctional and are unable to eliminate lung tumour cells.


Assuntos
Antígenos CD28/metabolismo , Complexo CD3/metabolismo , Transportador de Glucose Tipo 1/metabolismo , Glucose/metabolismo , Memória Imunológica/imunologia , Neoplasias Pulmonares/metabolismo , Derrame Pleural/metabolismo , Linfócitos T/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Neoplasias Pulmonares/imunologia , Ativação Linfocitária/imunologia , Masculino , Pessoa de Meia-Idade , Derrame Pleural/imunologia , Linfócitos T/metabolismo
4.
Mol Immunol ; 112: 387-393, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31288148

RESUMO

Programmed cell death 4 (Pdcd4) was found to be related to apoptosis upon first discovery. It was later found to play the role of tumor suppressor gene in a variety of tumors by inhibiting transcription and translation. Recently, it has been proposed that it may play an important role in some inflammatory diseases and in the immune response. In our previous study, deficiency of Pdcd4 was found to attenuate the formation of atherosclerotic plaques. This might be because deficiency of Pdcd4 may increase IL-10 expression and lipoautophagy by macrophages and attenuate the formation of foam cells. However, the effect of Pdcd4 on the subsets of T cells in hyperlipidemic mice still remained unclear. In the present study, results showed that Pdcd4 deficiency decreased the percentage of CD8+ T cells and increased that of regulatory T cells (Tregs) under hyperlipidemic conditions both in vitro and in vivo, which may be due to the reduced expression of co-stimulatory molecules CD28 and CD137, and the enhancive expression of co-inhibitory molecules CTLA-4. These results indicated that endogenous Pdcd4 promotes immune response mediated by T cells through regulation of the co-stimulatory molecules expression, which may contribute to the development of advanced atherosclerotic plaques. The current work provides new data to understand the role of Pdcd4 in different T cell subsets under hyperlipidemic microenvironment.


Assuntos
Proteínas Reguladoras de Apoptose/deficiência , Proteínas Reguladoras de Apoptose/metabolismo , Hiperlipidemias/metabolismo , Proteínas de Ligação a RNA/metabolismo , Subpopulações de Linfócitos T/metabolismo , Animais , Apoptose/fisiologia , Antígenos CD28/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Células Espumosas/metabolismo , Interleucina-10/metabolismo , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Placa Aterosclerótica/metabolismo , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/metabolismo
5.
Scand J Immunol ; 90(5): e12808, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31322752

RESUMO

CD4+ T cell immunotherapy has potential for treatment in HIV-infected patients. A large number of expanded CD4+ T cells and confirmation of functional-related phenotypes are required for ensuring the successful outcomes of treatment. Freshly isolated CD4+ T cells from healthy donors were activated with anti-CD3/28-coated magnetic beads at different bead-to-cell ratios and cultured in the absence and presence of IL-2 supplementation for 3 weeks. Fold expansion, cell viability, growth kinetic and lymphocyte subset identities were determined. Data demonstrated that a 1:1 bead-to-cell ratio rendered the highest expansion of 1044-fold with 88% viability and 99.5% purity followed by the 2:1 and 0.5:1 ratios. No significant difference in proliferation and phenotypes was found between non-IL-2 and IL-2 supplementation groups. Several specific surface molecule expressions of the expanded cells including chemokine receptors, adhesion molecules, co-stimulatory molecules, activation molecules, maturation markers, cytokine receptors and other molecules were altered when compared to the unexpanded cells. This optimized expansion protocol using the 1:1 bead-to-cell ratio of anti-CD3/28-coated magnetic beads and culture condition without IL-2 supplementation provided the satisfactory yield with good reproducibility. Specific surface molecule expressions of the expanded cells presented potential roles in proliferation, differentiation, homeostasis, apoptosis and organ homing.


Assuntos
Antígenos CD28/imunologia , Complexo CD3/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/transplante , Infecções por HIV/terapia , Imunoterapia Adotiva/métodos , Nanopartículas de Magnetita/uso terapêutico , Adulto , Proliferação de Células , Células Cultivadas , Materiais Revestidos Biocompatíveis , Humanos , Interleucina-2/imunologia , Ativação Linfocitária/imunologia , Resultado do Tratamento
6.
Dis Markers ; 2019: 5421985, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31089395

RESUMO

Human endogenous retrovirus-H long terminal repeat-associating protein 2 (HHLA2) and transmembrane and immunoglobulin domain containing 2 (TMIGD2) are new immune checkpoint molecules of the B7:CD28 family; however, little research has been performed on these immune checkpoint molecules. In this study, we used oral squamous cells carcinoma (OSCC) tissue microarrays and immunohistochemistry methods to investigate the expression patterns of HHLA2 and TMIGD2 in OSCC. After comparing the HHLA2 and TMIGD2 expression levels in OSCC, dysplasia, and mucosa, we found increased HHLA2 expression in OSCC and dysplasia, while the TMIGD2 expression was decreased in OSCC and dysplasia. Using the Kaplan-Meier method and log-rank test, we found that higher HHLA2 or TMIGD2 expression levels in OSCC indicate poor prognosis. Furthermore, two-tailed Pearson's statistical analysis revealed that the HHLA2 expression levels in OSCC, dysplasia, and mucosa were positively correlated with the T cell immunoglobulin and mucin-domain containing-3 (TIM3), lymphocyte-activation gene 3 (LAG3), B7 homolog 3 protein (B7-H3), B7 homolog 4 protein (B7H4), and V-domain Ig suppressor of T cell activation (VISTA) levels, while the TMIGD2 expression levels in OSCC, dysplasia, and mucosa were inversely correlated with the TIM3, LAG3, and B7H3 levels. Our current study demonstrates that HHLA2 may serve as an immune target for OSCC therapy and that the TMIGD2 expression level in OSCC could forecast patient prognosis.


Assuntos
Biomarcadores Tumorais/genética , Antígenos CD28/genética , Carcinoma de Células Escamosas/genética , Regulação Neoplásica da Expressão Gênica , Imunoglobulinas/genética , Neoplasias Bucais/genética , Biomarcadores Tumorais/metabolismo , Antígenos CD28/metabolismo , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Feminino , Humanos , Imunoglobulinas/metabolismo , Masculino , Neoplasias Bucais/metabolismo , Neoplasias Bucais/patologia
7.
Monoclon Antib Immunodiagn Immunother ; 38(2): 60-69, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31009338

RESUMO

CD28 superagonist (CD28SA), a therapeutic immunomodulatory monoclonal antibody triggered rapid and exaggerated activation of CD4+ effector memory T cells (TEMs) in humans with unwanted serious adverse effects. It is well known that distinct metabolic programs determine the fate and responses of immune cells. In this study, we show that human CD4+ TEMs stimulated with CD28SA adopt a metabolic program similar to those of tumor cells with enhanced glucose utilization, lipid biosynthesis, and proliferation in hypoxic conditions. Identification of metabolic profiles underlying hyperactive T cell activation would provide a platform to test safety of immunostimulatory antibodies.


Assuntos
Antígenos CD28/imunologia , Linfócitos T CD4-Positivos/imunologia , Glicólise/imunologia , Lipogênese/imunologia , Ativação Linfocitária/imunologia , Neoplasias/metabolismo , Acetilcoenzima A/metabolismo , Anticorpos Monoclonais/imunologia , Antígenos CD28/metabolismo , Proliferação de Células , Glucose/metabolismo , Humanos , Memória Imunológica , Neoplasias/imunologia , Neoplasias/patologia , Proteínas Quinases/metabolismo , Linfócitos T Reguladores/imunologia , Células Tumorais Cultivadas
8.
Nature ; 568(7750): 112-116, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30918399

RESUMO

Chimeric antigen receptors (CARs) are synthetic antigen receptors that reprogram T cell specificity, function and persistence1. Patient-derived CAR T cells have demonstrated remarkable efficacy against a range of B-cell malignancies1-3, and the results of early clinical trials suggest activity in multiple myeloma4. Despite high complete response rates, relapses occur in a large fraction of patients; some of these are antigen-negative and others are antigen-low1,2,4-9. Unlike the mechanisms that result in complete and permanent antigen loss6,8,9, those that lead to escape of antigen-low tumours remain unclear. Here, using mouse models of leukaemia, we show that CARs provoke reversible antigen loss through trogocytosis, an active process in which the target antigen is transferred to T cells, thereby decreasing target density on tumour cells and abating T cell activity by promoting fratricide T cell killing and T cell exhaustion. These mechanisms affect both CD28- and 4-1BB-based CARs, albeit differentially, depending on antigen density. These dynamic features can be offset by cooperative killing and combinatorial targeting to augment tumour responses to immunotherapy.


Assuntos
Antígenos de Neoplasias/imunologia , Antígenos de Neoplasias/metabolismo , Leucemia/imunologia , Receptores de Antígenos Quiméricos/imunologia , Linfócitos T/imunologia , Linfócitos T/metabolismo , Evasão Tumoral/imunologia , Ligante 4-1BB/imunologia , Animais , Antígenos CD28/imunologia , Citotoxicidade Imunológica , Feminino , Imunoterapia Adotiva , Leucemia/patologia , Masculino , Camundongos , Camundongos Endogâmicos NOD , Recidiva Local de Neoplasia/imunologia , Linfócitos T/citologia
9.
Autoimmun Rev ; 18(4): 325-333, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30825520

RESUMO

BACKGROUND: Myositis is a heterogeneous group of muscular auto-immune diseases with clinical and pathological criteria that allow the classification of patients into different sub-groups. Inclusion body myositis is the most frequent myositis above fifty years of age. Diagnosing inclusion body myositis requires expertise and is challenging. Little is known concerning the pathogenic mechanisms of this disease in which conventional suppressive-immune therapies are inefficacious. OBJECTIVES: Our aim was to deepen our understanding of the immune mechanisms involved in inclusion body myositis and identify specific biomarkers. METHODS: Using a panel of thirty-six markers and mass cytometry, we performed deep immune profiling of peripheral blood cells from inclusion body myositis patients and healthy donors, divided into two cohorts: test and validation cohorts. Potential biomarkers were compared to myositis controls (anti-Jo1-, anti-3-hydroxyl-3-methylglutaryl CoA reductase-, and anti-signal recognition particle-positive patients). RESULTS: Unsupervised analyses revealed substantial changes only within CD8+ cells. We observed an increase in the frequency of CD8+ cells that expressed high levels of T-bet, and containing mainly both effector and terminally differentiated memory cells. The senescent marker CD57 was overexpressed in CD8+T-bet+ cells of inclusion body myositis patients. As expected, senescent CD8+T-bet+ CD57+ cells of both patients and healthy donors were CD28nullCD27nullCD127null. Surprisingly, non-senescent CD8+T-bet+ CD57- cells in inclusion body myositis patients expressed lower levels of CD28, CD27, and CD127, and expressed higher levels of CD38 and HLA-DR compared to healthy donors. Using classification and regression trees alongside receiver operating characteristics curves, we identified and validated a frequency of CD8+T-bet+ cells >51.5% as a diagnostic biomarker specific to inclusion body myositis, compared to myositis control patients, with a sensitivity of 94.4%, a specificity of 88.5%, and an area under the curve of 0.97. CONCLUSION: Using a panel of thirty-six markers by mass cytometry, we identify an activated cell population (CD8+T-bet+ CD57- CD28lowCD27lowCD127low CD38+ HLA-DR+) which could play a role in the physiopathology of inclusion body myositis, and identify CD8+T-bet+ cells as a predominant biomarker of this disease.


Assuntos
Biomarcadores , Linfócitos T CD8-Positivos/fisiologia , Miosite de Corpos de Inclusão/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Antígenos CD28/metabolismo , Linfócitos T CD8-Positivos/imunologia , Humanos , Pessoa de Meia-Idade , Miosite de Corpos de Inclusão/imunologia , Proteínas com Domínio T/metabolismo
10.
Med Sci Monit ; 25: 1917-1927, 2019 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-30867406

RESUMO

BACKGROUND Numerous studies have been conducted on whether CD28 rs3116496 polymorphism affected cancer susceptibility, and these findings have been controversial. Thus, the purpose of this study was to assess the relationship between rs3116496 and susceptibility to cancer. MATERIAL AND METHODS The research published as of October 25, 2018 were comprehensively searched in PubMed, Embase, Cochrane Library and Chinese Wanfang database, CNKI, CBM. Statistical calculations performed using Stata12.0. RESULTS Overall analyses found that rs3116496 was a risk factor for cancer (C versus T, OR=1.14, 95% CI: 1.01-1.29, PH=0.003), and the heterogeneity was moderate (I²=53.3%). In subgroup analysis results by cancer types, the analysis showed that rs3116496 was a risk factor for breast cancer and leukemia. In the subgroup analysis by ethnicity, rs3116496 was a risk factor for cancer in the Asian population. After PHWE<0.05 was deleted, the analysis showed that rs3116496 might be related to the increased risk of colorectal cancer. CONCLUSIONS Our meta-analysis confirmed that rs3116496 was significantly related to cancer risk, especially in an Asian population, and was strongly correlated with the increased risk of breast cancer, leukemia and colorectal cancer.


Assuntos
Antígenos CD28/genética , Neoplasias/genética , Alelos , Grupo com Ancestrais do Continente Asiático/genética , Antígenos CD28/fisiologia , Estudos de Casos e Controles , Grupo com Ancestrais do Continente Europeu/genética , Frequência do Gene/genética , Predisposição Genética para Doença/genética , Genótipo , Humanos , Razão de Chances , Polimorfismo de Nucleotídeo Único/genética , Fatores de Risco
11.
Proc Natl Acad Sci U S A ; 116(3): 1007-1016, 2019 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-30598454

RESUMO

T cells proliferate vigorously following acute depletion of CD4+ Foxp3+ T regulatory cells [natural Tregs (nTregs)] and also when naive T cells are transferred to syngeneic, nTreg-deficient Rag1 -/- hosts. Here, using mice raised in an antigen-free (AF) environment, we show that proliferation in these two situations is directed to self ligands rather than food or commensal antigens. In both situations, the absence of nTregs elevates B7 expression on host dendritic cells (DCs) and enables a small subset of naive CD4 T cells with high self affinity to respond overtly to host DCs: bidirectional T/DC interaction ensues, leading to progressive DC activation and reciprocal strong proliferation of T cells accompanied by peripheral Treg (pTreg) formation. Likewise, high-affinity CD4 T cells proliferate vigorously and form pTregs when cultured with autologous DCs in vitro in the absence of nTregs: this anti-self response is MHCII/peptide dependent and elicited by the raised level of B7 on cultured DCs. The data support a model in which self tolerance is imposed via modulation of CD28 signaling and explains the pathological effects of superagonistic CD28 antibodies.


Assuntos
Proliferação de Células , Células Dendríticas/imunologia , Tolerância Imunológica , Modelos Imunológicos , Linfócitos T Reguladores/imunologia , Animais , Antígenos B7/genética , Antígenos B7/imunologia , Antígenos CD28/genética , Antígenos CD28/imunologia , Células Dendríticas/citologia , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/imunologia , Camundongos , Camundongos Knockout , Linfócitos T Reguladores/citologia
12.
Methods Mol Biol ; 1899: 103-118, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30649768

RESUMO

Alloantigen-specific hyporesponsiveness can be induced in alloreactive T cells contained within the whole peripheral blood mononuclear cell (PBMC) population by stimulating these responder cells ex vivo with HLA-mismatched stimulator PBMC as the antigen presenting cell (APC) source, in the presence of a CD28 costimulation blocking agent. As a result of this approach, specific alloreactivity is markedly decreased (by 1-2 logs), but third-party alloresponses and in vitro responses relying on the activation of pathogen- and tumor-associated antigen T-cell functional activities are not globally impinged upon (Guinan et al. N Engl J Med 340(22):1704-1714, 1999, Davies et al. Transplantation 86(6):854-864, 2008, Davies et al. Cell Transplant 21(9):2047-61, 2012). This method has been used clinically to alloanergize bone marrow and PBMC allografts, creating ex vivo cell therapies for adoptive transfer to blood cancer patients at high risk of disease relapse whose best option was to receive haploidentical hematopoietic cell transplants. These early phase trials consisting of, or containing, alloanergized T-cell infusions show promise in reducing graft-versus-host disease (GvHD), providing more rapid immune reconstitution, and decreasing severe post-transplant infectious complications and disease relapse. Herein, we describe this straightforward technique for generating alloanergized PBMC as it is performed in the research lab setting using belatacept for CD28-mediated costimulatory blockade (CSB) and PBMC isolated by Ficoll Hypaque gradient centrifugation as responders and APC. We also describe methods for evaluating subsequent alloproliferation to first and third party stimulation as well as assessment of cell division, pathogen-specific immunity, or allosuppression. The technique has successfully been transferred to collaborating labs, largely owing to the flexibility of using fresh or frozen PBMC, the lack of a requirement for specially isolated APC populations, and the ability to scale up or scale down the cell numbers that are to be anergized.


Assuntos
Antígenos CD28/imunologia , Tolerância Imunológica , Ativação Linfocitária/imunologia , Teste de Cultura Mista de Linfócitos/métodos , Linfócitos T Reguladores/imunologia , Células Apresentadoras de Antígenos/imunologia , Medula Óssea/imunologia , Transplante de Células-Tronco Hematopoéticas , Humanos , Isoantígenos/imunologia , Leucócitos Mononucleares/imunologia , Transplante Homólogo
13.
Gene ; 688: 84-92, 2019 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-30529248

RESUMO

Cluster of differentiation 28 (CD28) is a co-stimulatory receptor found on the surface of T cells. Takifugu obscurus is a kind of anadromous fish species. In this study, the full-length sequence of To-CD28 was obtained, including a 672-bp open reading frame that encodes a peptide chain of 223 amino acids. The phylogenetic analysis showed that To-CD28 is similar to the CD28 protein in Takifugu rubripes. The total hematocyte count distinctly decreased after TBT-Cl exposure, showing the adverse effects of TBT-Cl invasion and self-adjusting ability upon To-CD28 accumulation. The production of reactive oxygen species increased, demonstrating the oxidation resistance of T. obscurus when exposed to TBT-Cl. The tissue expression patterns indicated To-CD28 is a widely distributed receptor in T. obscurus. Its high expression in the liver and gill suggests that To-CD28 could be potentially functioned in TBT-Cl toxic process. The mRNA levels of To-CD28 and relative genes in the TLR-MyD88 signal pathway were significantly up-regulated under TBT-Cl exposure. The immunohistochemistry also showed that the To-CD28 protein signal was enhanced under TBT-Cl exposure, which proved that the positive protection of To-CD28 for maintaining homeostasis. Our study indicated that To-CD28 might participate in the toxicity mechanism upon TBT-Cl exposure and regulate homeostasis stability of T. obscurus.


Assuntos
Antígenos CD28/metabolismo , Fator 88 de Diferenciação Mieloide/metabolismo , Transdução de Sinais/efeitos dos fármacos , Takifugu/metabolismo , Compostos de Trialquitina/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Brânquias/metabolismo , Homeostase/efeitos dos fármacos , Filogenia , RNA Mensageiro/metabolismo , Rios , Transdução de Sinais/fisiologia , Regulação para Cima/efeitos dos fármacos
14.
Cancer Sci ; 110(2): 530-539, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30548441

RESUMO

B7-H5 and its cognate receptor CD28H are T lymphocyte second signaling transduction molecules. Here we aimed to explore the function of this pathway in pancreatic cancer in vitro and in vivo, and evaluated the clinical significance in 136 patients with pancreatic ductal adenocarcinoma enrolled from January 2012 to February 2017 in our hospital. Surgical tumor specimens were collected for immunohistochemical staining to evaluate B7-H5 expression. Patients' baseline characteristics, including gender, age, tumor size, tumor location, tumor grading, clinical TNM staging, tumor infiltrating lymphocytes, CA19-9 and chemotherapy treatment, along with the subsequent follow-up data, were documented and analyzed. When co-cultured with T cells, pancreatic cancer PC cells with high B7-H5 expression induced a more potent immune reaction, indicated by elevated cytokine release and increased proliferation of T lymphocytes compared with cells exhibiting low B7-H5 expression. Xenograft pancreatic tumors derived from high B7-H5 expression PC cells exhibited attenuated growth compared to tumors from low B7-H5 expression cells after transfusion with T lymphocytes in immune-deficient mice. Of the 136 PDAC tumor tissues, 93 (68.38%) were strong and 43 (31.62%) were weak B7-H5 expression. Patients with strong B7-H5 expression had significantly longer overall survival than those with weak expression (median: 16.5 vs 11.5 months, P = .017). TNM staging, tumor location and subsequent chemotherapy were also prognostic factors in these patients. Collectively, B7-H5/CD28H is a co-stimulatory signal pathway, and expression of B7-H5 is associated with improved disease prognosis in patients with pancreatic cancer.


Assuntos
Adenocarcinoma/metabolismo , Antígenos B7/metabolismo , Antígenos CD28/metabolismo , Carcinoma Ductal Pancreático/metabolismo , Transdução de Sinais/fisiologia , Adenocarcinoma/patologia , Adulto , Idoso , Animais , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Feminino , Humanos , Linfócitos do Interstício Tumoral/metabolismo , Linfócitos do Interstício Tumoral/patologia , Masculino , Camundongos , Pessoa de Meia-Idade , Estadiamento de Neoplasias/métodos , Prognóstico , Linfócitos T/metabolismo , Linfócitos T/patologia
15.
Front Immunol ; 9: 2864, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30564247

RESUMO

T cell activation is initiated upon ligand engagement of the T cell receptor (TCR) and costimulatory receptors. The CD28 molecule acts as a major costimulatory receptor in promoting full activation of naive T cells. However, despite extensive studies, why naive T cell activation requires concurrent stimulation of both the TCR and costimulatory receptors remains poorly understood. Here, we explore this issue by analyzing calcium response as a key early signaling event to elicit T cell activation. Experiments using mouse naive CD4+ T cells showed that engagement of the TCR or CD28 with the respective cognate ligand was able to trigger a rise in fluctuating calcium mobilization levels, as shown by the frequency and average response magnitude of the reacting cells compared with basal levels occurred in unstimulated cells. The engagement of both TCR and CD28 enabled a further increase of these two metrics. However, such increases did not sufficiently explain the importance of the CD28 pathways to the functionally relevant calcium responses in T cell activation. Through the autocorrelation analysis of calcium time series data, we found that combined but not separate TCR and CD28 stimulation significantly prolonged the average decay time (τ) of the calcium signal amplitudes determined with the autocorrelation function, compared with its value in unstimulated cells. This increasement of decay time (τ) uniquely characterizes the fluctuating calcium response triggered by concurrent stimulation of TCR and CD28, as it could not be achieved with either stronger TCR stimuli or by co-engaging both TCR and LFA-1, and likely represents an important feature of competent early signaling to provoke efficient T cell activation. Our work has thus provided new insights into the interplay between the TCR and CD28 early signaling pathways critical to trigger naive T cell activation.


Assuntos
Antígenos CD28/metabolismo , Linfócitos T CD4-Positivos/imunologia , Sinalização do Cálcio/imunologia , Ativação Linfocitária , Receptores de Antígenos de Linfócitos T/metabolismo , Animais , Células Apresentadoras de Antígenos , Antígenos CD28/imunologia , Linfócitos T CD4-Positivos/metabolismo , Células COS , Células Cultivadas , Cercopithecus aethiops , Técnicas de Cocultura , Antígeno-1 Associado à Função Linfocitária/imunologia , Antígeno-1 Associado à Função Linfocitária/metabolismo , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos CBA , Camundongos Transgênicos , Cultura Primária de Células , Receptores de Antígenos de Linfócitos T/imunologia
16.
Fontilles, Rev. leprol ; 31(6): 443-466, sept.-dic. 2018. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-178459

RESUMO

Objetivos: 1. Evaluar la immunohistoquimica de los granulomas de la lepra en las muestras de biopsias cutáneas de pacientes con lepra tuberculoide y lepromatosa, con respecto a la presencia y distribución de células T CD4+, CD8+ y CD28+, células CD 68+ y células CD1a+. 2. Evaluar los hallazgos inmunohistoquimicos observados en leprorreacciones. Metodología: Estudio descriptivo. Se seleccionaron para el estudio biopsias cutaneas, en las que se había diagnosticado clínica e histopatologicamente lepra entre el 1.8.2016 al 31.5.2017 en el Instituto Medico Gubernamental, Kozhikode. Se estudió la immunohistoquimica de las lesiones cutáneas en lepra y leprorreacciones, observando específicamente la distribución de células CD4/ CD8/ CD28/ CD68/ CD1a en la lepra en distintos escenarios. Resultados: En el estudio se incluyeron veintiséis casos tuberculoides y 14 lepromatosos. Todos los granulomas independientemente del tipo de enfermedad presentaron tinción positiva por CD4 y CD68. Dos de los 14 casos lepromatosos (14・3%), y 15/26 (57・7%) de las muestras tuberculoides presentaron expresion CD4 de moderada a fuerte. Se detectó negatividad CD28 en cuatro casos tuberculoides (15・4%) y en 10 lepromatosos (71・4%). La expresion CD4 moderada a fuerte se detectó en más del 70% de los T1R incremento mientras que en los demás grupos solo fue de 20%–50%. Más del 80% de las T1R estáticas e incremento presentaban positividad CD28, mayor de que el 30%-50% registrado en otros grupos. Conclusiones: Los resultados revelan que la inmunohistoquimica tiene un papel en aclarar los complejos procesos inmunológicos empleados en la lepra y las leprorreacciones


Objectives: 1. To study the immunohistochemistry of leprosy granulomas in the skin biopsy specimens of patients with tuberculoid and lepromatous leprosy, with respect to the presence and arrangement of CD4+, CD8+ and CD28+ T cells, CD 68+ cells and CD1a+ cells. 2. To study the immunohistochemistry findings observed in leprosy reactions. Design: Descriptive study. Skin biopsies in which the clinical and histopathological diagnosis of leprosy was reported between 1.8.2016 to 31.5.2017 in the Government Medical College, Kozhikode, were selected for the study. Immunohistochemistry of the skin lesions in leprosy and leprosy reactions was studied, looking specifically for the distribution of CD4/ CD8/ CD28/ CD68/ CD1a positive cells in leprosy at different scenarios. Results: Twenty-six tuberculoid and 14 lepromatous cases were included in the study. All granulomas irrespective of disease type showed positive staining for CD4 and CD68. Two of the 14 lepromatous leprosy cases (14・3%), and 15/26 (57・7%) tuberculoid specimens manifested moderate to strong CD4 expression. CD28 negativity was documented in four tuberculoid (15・4%) and 10 lepromatous cases (71・4%). Moderate to strong CD4 expression was noted in more than 70% of upgrading T1R while a similar finding was documented in only 20%-50% of other groups. More than 80% of static and upgrading T1R showed CD28 positivity, which was higher than the 30%-50% positivity recorded in other groups. Conclusions: The observations of the current study indicate a role for immunohistochemistry analysis in delineating the complex immunological processes involved in leprosy and leprosy reactions


Assuntos
Humanos , Imuno-Histoquímica , Granuloma/diagnóstico , Hanseníase Virchowiana/diagnóstico , Hanseníase Tuberculoide/diagnóstico , Biópsia , Granuloma/patologia , Hanseníase Virchowiana/patologia , Hanseníase Tuberculoide/patologia , Epiderme/citologia , Epiderme/patologia , Antígenos CD28/análise , Antígenos CD1/análise , Antígenos CD4/análise , Antígenos CD8/análise
17.
Proc Natl Acad Sci U S A ; 115(34): E8027-E8036, 2018 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-30087184

RESUMO

Activated T cells undergo metabolic reprogramming and effector-cell differentiation but the factors involved are unclear. Utilizing mice lacking DUSP6 (DUSP6-/-), we show that this phosphatase regulates T cell receptor (TCR) signaling to influence follicular helper T (TFH) cell differentiation and T cell metabolism. In vitro, DUSP6-/- CD4+ TFH cells produced elevated IL-21. In vivo, TFH cells were increased in DUSP6-/- mice and in transgenic OTII-DUSP6-/- mice at steady state. After immunization, DUSP6-/- and OTII-DUSP6-/- mice generated more TFH cells and produced more antigen-specific IgG2 than controls. Activated DUSP6-/- T cells showed enhanced JNK and p38 phosphorylation but impaired glycolysis. JNK or p38 inhibitors significantly reduced IL-21 production but did not restore glycolysis. TCR-stimulated DUSP6-/- T cells could not induce phosphofructokinase activity and relied on glucose-independent fueling of mitochondrial respiration. Upon CD28 costimulation, activated DUSP6-/- T cells did not undergo the metabolic commitment to glycolysis pathway to maintain viability. Unexpectedly, inhibition of fatty acid oxidation drastically lowered IL-21 production in DUSP6-/- TFH cells. Our findings suggest that DUSP6 connects TCR signaling to activation-induced metabolic commitment toward glycolysis and restrains TFH cell differentiation via inhibiting IL-21 production.


Assuntos
Diferenciação Celular/fisiologia , Fosfatase 6 de Especificidade Dupla , Glicólise/fisiologia , Receptores de Antígenos de Linfócitos T , Transdução de Sinais/fisiologia , Linfócitos T Auxiliares-Indutores , Animais , Formação de Anticorpos/fisiologia , Antígenos CD28/genética , Antígenos CD28/imunologia , Antígenos CD28/metabolismo , Fosfatase 6 de Especificidade Dupla/genética , Fosfatase 6 de Especificidade Dupla/imunologia , Fosfatase 6 de Especificidade Dupla/metabolismo , Imunoglobulina G/imunologia , Imunoglobulina G/metabolismo , Interleucinas/genética , Interleucinas/imunologia , Interleucinas/metabolismo , MAP Quinase Quinase 4/genética , MAP Quinase Quinase 4/imunologia , MAP Quinase Quinase 4/metabolismo , Camundongos , Camundongos Knockout , Mitocôndrias/genética , Mitocôndrias/imunologia , Mitocôndrias/metabolismo , Consumo de Oxigênio/fisiologia , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/imunologia , Receptores de Antígenos de Linfócitos T/metabolismo , Linfócitos T Auxiliares-Indutores/citologia , Linfócitos T Auxiliares-Indutores/imunologia , Linfócitos T Auxiliares-Indutores/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/imunologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
18.
Cancer Immunol Immunother ; 67(11): 1695-1707, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30128739

RESUMO

Tumor-mediated immunosuppression via regulatory T-cells is a key player among the various immune-escape mechanisms in multiple myeloma. We analyzed the generation, distribution, function and immunophenotype of CD8+CD28- regulatory T-cells in patients with multiple myeloma. Functionality of CD8+CD28- T-cells was assessed by immunological assays using ex vivo generated antigen-specific T-cells from patients with plasma cell dyscrasias and healthy donors. Detailed analysis of distribution, immunophenotype and cytotoxic potential of CD8+CD28- T-cells was performed by flow cytometry and ELISA. We found that the amount of CD8+CD28- T-cells was directly correlated with the suppression of antigen-specific T-cell responses in patients with plasma cell dyscrasia. Analyzing the CD8+CD28- T-cells in detail, increased numbers of these cells were observed in the bone marrow (i.e., tumor microenvironment) of patients with plasma cell dyscrasia. Furthermore, we identified the expression of lymphocyte function-associated antigen 1 (LFA-1) as a marker of immunosuppression and defined the CD8+CD28-CD57+LFA-1high population as the relevant immunosuppressive compartment. These regulatory T-cells act as immunosuppressors via soluble factors and incubation with IL-10 augmented their immunosuppressive capacity. The immunosuppressive regulatory network of IL-10 and the CD8+CD28-CD57+LFA-1high regulatory T-cells show unique characteristics and contribute to the tumor immune escape mechanism in patients with multiple myeloma.


Assuntos
Antígenos CD28/imunologia , Antígenos CD8/imunologia , Linfócitos T CD8-Positivos/imunologia , Interleucina-10/farmacologia , Mieloma Múltiplo/imunologia , Paraproteinemias/imunologia , Subpopulações de Linfócitos T/imunologia , Linfócitos T Reguladores/imunologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Estudos de Casos e Controles , Células Cultivadas , Humanos , Ativação Linfocitária , Mieloma Múltiplo/metabolismo , Mieloma Múltiplo/patologia , Paraproteinemias/metabolismo , Paraproteinemias/patologia , Subpopulações de Linfócitos T/efeitos dos fármacos , Linfócitos T Citotóxicos/efeitos dos fármacos , Linfócitos T Citotóxicos/imunologia , Linfócitos T Reguladores/efeitos dos fármacos
19.
J Immunol Res ; 2018: 2484825, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30057914

RESUMO

Blockade of the CD28:CD80/86 costimulatory pathway has been shown to be potent in blocking T cell activation in vitro and in vivo. The costimulation blocker CTLA4Ig has been approved for the treatment of autoimmune diseases and transplant rejection. The therapeutic application of regulatory T cells (Tregs) has recently gained much attention for its potential of improving allograft survival. However, neither costimulation blockade with CTLA4Ig nor Treg therapy induces robust tolerance on its own. Combining CTLA4Ig with Treg therapy would be an attractive approach for minimizing immunosuppression or for possibly achieving tolerance. However, since the CD28 pathway is more complex than initially thought, the question arose whether blocking CD80/86 would inadvertently impact immunological tolerance by interfering with Treg generation and function. We therefore wanted to investigate the compatibility of CTLA4Ig with regulatory T cells by evaluating direct effects of CTLA4Ig on murine Treg generation and function in vitro. For generation of polyclonal-induced Tregs, we utilized an APC-free in vitro system and added titrated doses of CTLA4Ig at different time points. Phenotypical characterization by flow cytometry and functional characterization in suppressor assays did not reveal negative effects by CTLA4Ig. The costimulation blocker CTLA4Ig does not impair but rather improves murine iTreg generation and suppressor function in vitro.


Assuntos
Abatacepte/farmacologia , Rejeição de Enxerto/terapia , Imunossupressores/farmacologia , Transplante de Órgãos , Linfócitos T Reguladores/fisiologia , Abatacepte/uso terapêutico , Animais , Antígeno B7-1/metabolismo , Antígeno B7-2/metabolismo , Antígenos CD28/metabolismo , Diferenciação Celular , Células Cultivadas , Feminino , Rejeição de Enxerto/imunologia , Imunossupressão , Imunossupressores/uso terapêutico , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos C57BL , Fator de Crescimento Transformador beta/metabolismo
20.
Ecotoxicol Environ Saf ; 162: 208-217, 2018 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-29990733

RESUMO

Zearalenone (ZEA) is particularly toxic to the female reproductive system. Nevertheless, the effect of ZEA on the immune system is still not fully understood. The following study investigates the effects and mechanism of ZEA on mouse T cell activation in vitro. Briefly, T lymphocytes were extracted from primary splenic lymphocyte in mice, activated by concanavalin A, and then were exposed to different concentrations of ZEA for a certain period of time. Flow cytometry was used to detect the expression of activating and co-stimulatory molecules, and the secretion of cytokines in T cells at various stages. The expression of initiation regulatory protein in T cell activation, nuclear factor protein and co-stimulatory molecule related PI3K-Akt-mTOR signaling pathway proteins were detected by western blot. Our data showed that ZEA exposure inhibits the activity of T cell, and inhibits the expression of different activation signals in T cell. Additionally, ZEA exposure reduces the expression of initiative regulatory protein, i.e. LAT, Lck, Zap-70 during the activation of T cells. Thus, the results showed that ZEA exposure inhibits the formation and transmission of activated signal in T cells, interferes with signal pathway of T cell activation nuclear factor NFAT and NFκB, and decreases the secretion of cytokines after activation. Moreover, ZEA exposure interferes with co-stimulatory molecule CD28 during T cell activation, and with the activity of the PI3K-Akt-mTOR signaling pathway downstream of CD28. To conclude, our results indicated that ZEA toxin interferes with the activation of mouse T lymphocytes by affecting TCR signal and co-stimulatory signal, thus playing an essential role in immune toxicity.


Assuntos
Ativação Linfocitária/efeitos dos fármacos , Linfócitos T/efeitos dos fármacos , Zearalenona/toxicidade , Animais , Antígenos CD28/metabolismo , Células Cultivadas , Citocinas/metabolismo , Camundongos , NF-kappa B/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais/efeitos dos fármacos
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