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1.
Science ; 368(6493): 897-901, 2020 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-32381591

RESUMO

Cytotoxic T lymphocytes (CTLs) kill infected and cancerous cells. We detected transfer of cytotoxic multiprotein complexes, called supramolecular attack particles (SMAPs), from CTLs to target cells. SMAPs were rapidly released from CTLs and were autonomously cytotoxic. Mass spectrometry, immunochemical analysis, and CRISPR editing identified a carboxyl-terminal fragment of thrombospondin-1 as an unexpected SMAP component that contributed to target killing. Direct stochastic optical reconstruction microscopy resolved a cytotoxic core surrounded by a thrombospondin-1 shell of ~120 nanometer diameter. Cryo-soft x-ray tomography analysis revealed that SMAPs had a carbon-dense shell and were stored in multicore granules. We propose that SMAPs are autonomous extracellular killing entities that deliver cytotoxic cargo targeted by the specificity of shell components.


Assuntos
Citotoxicidade Imunológica , Granzimas/metabolismo , Complexos Multiproteicos/metabolismo , Perforina/metabolismo , Linfócitos T Citotóxicos/metabolismo , Trombospondina 1/metabolismo , Sistemas CRISPR-Cas , Exocitose , Edição de Genes , Humanos , Células K562 , Trombospondina 1/genética , Tomografia por Raios X
2.
Cancer Immunol Immunother ; 69(5): 745-758, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32047957

RESUMO

BACKGROUND: Osteosarcoma (OS) is the most common malignant bone tumor and the prognosis of advanced cases is still poor. Recently, there have been several reports suggesting the relationship between innate immunity and OS, but the detailed mechanism is unknown. We demonstrate the relationship between OS and Toll-like receptor 4 (TLR4) which is one of the most important factors in innate immunity. METHODS: We established a syngenic mouse tumor model using C3H/HeN, C3H/HeJ mouse and a highly metastatic OS cell line, LM8. TLR4 activation with lipopolysaccharide (LPS) was performed on both mice and its influence on the progression of OS was evaluated. We also performed CD8 + cells depletion to examine the influence on TLR4 activation effects. RESULTS: Tumor volume of C3H/HeN mice was significantly smaller and overall survival of C3H/HeN mice was significantly longer than C3H/HeJ mice. We found more CD8+ cells infiltrating in lung metastases of C3H/HeN mice and depletion of CD8+ cells canceled the antitumor effects of LPS. CONCLUSION: TLR4 activation by LPS increased CD8+ cells infiltrating into lung metastases and suppressed OS progression in the mouse model. TLR4 activation may suppress the progression of OS via stimulating CD8+ cells and can be expected as a novel treatment for OS.


Assuntos
Neoplasias Ósseas/imunologia , Neoplasias Pulmonares/imunologia , Osteossarcoma/imunologia , Linfócitos T Citotóxicos/imunologia , Receptor 4 Toll-Like/metabolismo , Adjuvantes Imunológicos/administração & dosagem , Adolescente , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Ósseas/mortalidade , Neoplasias Ósseas/patologia , Neoplasias Ósseas/terapia , Linhagem Celular Tumoral/transplante , Quimioterapia Adjuvante , Criança , Pré-Escolar , Modelos Animais de Doenças , Progressão da Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Lipídeo A/administração & dosagem , Lipídeo A/análogos & derivados , Lipopolissacarídeos/administração & dosagem , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/secundário , Neoplasias Pulmonares/terapia , Depleção Linfocítica , Masculino , Camundongos , Pessoa de Meia-Idade , Osteossarcoma/mortalidade , Osteossarcoma/secundário , Osteossarcoma/terapia , Prognóstico , Intervalo Livre de Progressão , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia , Linfócitos T Citotóxicos/metabolismo , Receptor 4 Toll-Like/agonistas , Receptor 4 Toll-Like/imunologia , Carga Tumoral/imunologia , Adulto Jovem
3.
Cancer Immunol Immunother ; 69(5): 789-797, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32055919

RESUMO

CD160 is an Ig-like glycoprotein expressed by the majority of circulating natural killer cells and γδ T cells. Whether CD160 could regulate CD8+ T-cell functions remains unknown. In this study, we investigated the effects of CD160 on CD8+ T cells in pancreatic cancer. First, we found that the frequency of PD-1+ cells was comparable between CD160+ and CD160-CD8+ T cells, with the former presenting significantly higher PD-1 expression level. In contrast, the frequency of TIM-3+ cells was higher among CD160+ cells but the expression level was comparable between CD160+ and CD160-CD8+ T cells. The IFN-γ and IL-2-expressing CD8+ T cells, directly ex vivo, were highly enriched in the CD160+ subset. However, when CD160+ and CD160-CD8+ T cells were stimulated, the proliferation levels of CD160+ and CD160- cells were initially comparable, but were significantly lower in CD160+CD8+ T cells than in CD160-CD8+ T cells later on. The IFN-γ and IL-2 transcription levels were initially higher in CD160+CD8+ T cells, but eventually reduced in CD160+CD8+ T cells compared to CD160-CD8+ T cells. Also, CD160+CD8+ T cells presented lower cytotoxic capacity than CD160-CD8+ T cells. Interestingly, we observed that tumor-infiltrating CD8+ T cells were significantly enriched with the CD160+ subset in pancreatic cancer patients. In addition, patients with higher frequencies of tumor CD160+CD8+ T cells presented lower survival. Overall, these data demonstrated that tumor-infiltrating CD8+ T cells were enriched with the CD160+ subset in pancreatic cancer, with active effector responses directly ex vivo but limited potential for further activation.


Assuntos
Antígenos CD/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linfócitos do Interstício Tumoral/imunologia , Neoplasias Pancreáticas/imunologia , Receptores Imunológicos/metabolismo , Linfócitos T Citotóxicos/imunologia , Adulto , Idoso , Antígenos CD/imunologia , Biópsia , Linfócitos T CD8-Positivos/metabolismo , Feminino , Proteínas Ligadas por GPI/imunologia , Proteínas Ligadas por GPI/metabolismo , Humanos , Ativação Linfocitária , Linfócitos do Interstício Tumoral/metabolismo , Masculino , Pessoa de Meia-Idade , Pâncreas/citologia , Pâncreas/imunologia , Pâncreas/patologia , Pâncreas/cirurgia , Pancreatectomia , Neoplasias Pancreáticas/sangue , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/cirurgia , Receptores Imunológicos/imunologia , Análise de Sobrevida , Linfócitos T Citotóxicos/metabolismo , Fatores de Tempo
4.
Nat Commun ; 11(1): 622, 2020 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-32001695

RESUMO

The failure of immunotherapies in immune-excluded tumor (IET) is largely ascribed to the void of intratumoral cytotoxic T cells (CTLs). The major obstacles are the excessive stroma, defective vasculatures and the deficiency of signals recruiting CTLs. Here we report a dual-mechanism based CTLs infiltration enhancer, Nano-sapper, which can simultaneously reduce the physical obstacles in tumor microenvironment and recruiting CTLs to potentiate immunotherapy in IET. Nano-sapper consists a core that co-loaded with antifibrotic phosphates-modified α-mangostin and plasmid encoding immune-enhanced cytokine LIGHT. Through reversing the abnormal activated fibroblasts, decreasing collagen deposition, normalizing the intratumoral vasculatures, and in situ stimulating the lymphocyte-recruiting chemoattractants expression, Nano-sapper paves the road for the CTLs infiltration, induces the intratumoral tertiary lymphoid structures, thus reshapes tumor microenvironment and potentiates checkpoint inhibitor against IET. This study demonstrates that the combination of antifibrotic agent and immune-enhanced cytokine might represent a modality in promoting immunotherapy against IET.


Assuntos
Imunoterapia , Nanomedicina/métodos , Neoplasias/imunologia , Neoplasias/terapia , Linfócitos T Citotóxicos/metabolismo , Animais , Citocinas/metabolismo , Modelos Animais de Doenças , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Células NIH 3T3 , Neoplasias/irrigação sanguínea , Receptor de Morte Celular Programada 1 , Microambiente Tumoral
5.
Cancer Immunol Immunother ; 69(4): 629-640, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32020256

RESUMO

The efficacy of immunotherapies in cancer treatment becomes more and more apparent not only in different solid tumors but also in hematological malignancies. However, in acute myeloid leukemia (AML), mechanisms to increase the efficacy of immunotherapeutic approaches have to be further elucidated. Targeting leukemic progenitor and stem cells (LPC/LSC) by specific CTL, for instance, in an adjuvant setting or in minimal residual disease, might be an option to prevent relapse of AML or to treat MRD. Therefore, we investigated the influence of immune checkpoint inhibitors on LAA-specific immune responses by CTL against leukemic myeloid blasts and colony-forming cells including leukemic progenitor cells (CFC/LPC). In functional immunoassays like CFU/CFI (colony-forming units/immunoassays) and ELISpot analysis, we detected specific LAA-directed immune responses against CFC/LPC that are postulated to be the source population of relapse of the disease. The addition of nivolumab (anti-PD-1) significantly increases LAA-directed immune responses against CFC/LPC, no effect is seen when ipilimumab (anti-CTLA-4) is added. The combination of ipilimumab and nivolumab does not improve the effect compared to nivolumab alone. The anti-PD1-directed immune response correlates to PD-L1 expression on progenitor cells. Our data suggest that immunotherapeutic approaches have the potential to target malignant CFC/LPC and anti-PD-1 antibodies could be an immunotherapeutic approach in AML. Moreover, combination with LAA-directed vaccination strategies might also open interesting application possibilities.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Ipilimumab/uso terapêutico , Leucemia Mieloide/terapia , Células-Tronco Neoplásicas/efeitos dos fármacos , Nivolumabe/uso terapêutico , Linfócitos T/imunologia , Doença Aguda , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/imunologia , Antígeno B7-H1/metabolismo , Antígeno CTLA-4/antagonistas & inibidores , Antígeno CTLA-4/imunologia , Antígeno CTLA-4/metabolismo , Humanos , Imunoterapia/métodos , Ipilimumab/administração & dosagem , Leucemia Mieloide/imunologia , Leucemia Mieloide/metabolismo , Células-Tronco Neoplásicas/imunologia , Células-Tronco Neoplásicas/metabolismo , Nivolumabe/administração & dosagem , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/imunologia , Receptor de Morte Celular Programada 1/metabolismo , Linfócitos T/metabolismo , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/metabolismo , Resultado do Tratamento
6.
PLoS One ; 15(1): e0227314, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31951638

RESUMO

Acute lymphoblastic leukemia (ALL) is the most common cancer in children around the globe. Mexico City has one of the highest incidence rates of childhood leukemia worldwide with 49.5 cases per million children under the age of 15 which is similar to that reported for Hispanic populations living in the United States. In addition, it has been noted a dismal prognosis in Mexican and Hispanic ALL pediatric population. Although ALL, like cancer in general, has its origins in endogenous, exogenous, and genetic factors, several studies have shown that the immune system also plays a deterministic role in cancer development. Among various elements of the immune system, T lymphocytes and NK cells seem to dominate the immune response against leukemia. The aim of the present study was to perform a phenotypic and functional characterization of NK cells in ALL Mexican children at the moment of diagnosis and before treatment initiation. A case-control study was conducted by the Mexican Interinstitutional Group for the Identification of the Causes of Childhood Leukemia (MIGICCL). 41 cases were incident ALL children younger than 17 years old and residents of Mexico City. 14 controls were children without leukemia, matched by age and sex with cases. NK cell function was evaluated by degranulation assays towards K562 cells and SLAM-associated protein (SAP) expression was measured by intracellular staining. All assays were performed using peripheral blood mononuclear cells from controls and patients. The results indicate that NK mediated cytotoxicity, measured by CD107a degranulation assays in response to K562 cells, was reduced in ALL patients compared to controls. Interestingly, an impaired NK cell killing of target cells was not equally distributed among ALL patients. In contrast to patients classified as high-risk, standard-risk patients did not display a significant reduction in NK cell-mediated cytotoxicity. Moreover, patients presenting a leukocyte count ≥ 50,000xmm3 displayed a reduction in NK-cell mediated cytotoxicity and a reduction in SAP expression, indicating a positive correlation between a reduced SAP expression and an impaired NK cell-mediated citotoxicity. In the present study it was observed that unlike patients with standard-risk, NK cells from children presenting high-risk ALL, harbor an impaired cytotoxicity towards K562 at diagnosis. In addition, NK cell function was observed to be compromised in patients with a leukocyte count ≥50,000xmm3, where also it was noticed a decreased expression of SAP compared to patients with a leukocyte count <50,000xmm3. These data indicate NK cell-mediated cytotoxicity is not equally affected in ALL patients, nevertheless a positive correlation between low SAP expression and decreased NK cell-mediated cytotoxicity was observed in ALL patients with a leukocyte count ≥50,000xmm3. Finally, an abnormal NK cell-mediated cytotoxicity may represent a prognostic factor for high-risk acute lymphoblastic leukemia.


Assuntos
Células Matadoras Naturais/imunologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/sangue , Proteína Associada à Molécula de Sinalização da Ativação Linfocitária/genética , Linfócitos T Citotóxicos/metabolismo , Adolescente , Estudos de Casos e Controles , Degranulação Celular/genética , Degranulação Celular/imunologia , Criança , Pré-Escolar , Citotoxicidade Imunológica/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Células K562 , Células Matadoras Naturais/patologia , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/patologia , Proteína 1 de Membrana Associada ao Lisossomo/genética , Masculino , México , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Linfócitos T Citotóxicos/patologia
7.
Tumori ; 106(1): 55-63, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31451071

RESUMO

PURPOSE: The present study aims to investigate the efficacy and mechanisms of peroxisome proliferator-activated receptor γ coactivator 1-α agonist, as adjuvant to programmed death-1 (PD-1) blockade in hyporesponsive lung cancer cells-derived in vivo tumor model, using bezafibrate. METHODS: Mouse Lewis lung carcinoma (LLC) xenograft models were established and treated with programmed death-ligand 1 (PD-L1) monoclonal antibodies with or without bezafibrate. Tumors or peripheral blood of mice were harvested to investigate the quality, quantity, and function as well as energetic metabolism of cytotoxic T lymphocytes (CTLs) by flow cytometry or quantitative real-time polymerase chain reaction. RESULTS: The combination of bezafibrate plus anti-PD-L1 reached synergistic tumoricidal effect in LLC xenograft mouse models, even though bezafibrate alone had no effect on tumor growth. Bezafibrate significantly facilitated CD8+ T cells infiltrating into tumor tissues by enhancing the expression of CXCL9 and CXCL10 within tumors as well as the receptor CXCR3 in infiltrating CTLs. Activated CTLs within tumors were also significantly upregulated by bezafibrate. Further data demonstrated that bezafibrate treatment could maintain the survival and functional capacity of tumor-infiltrating CTLs. Moreover, cellular reactive oxygen species in infiltrating CTLs and fatty acid oxidation (FAO)-related genes (PGC-1α, Cpt1a, and LCAD) expression within tumors were significantly increased after treatment with bezafibrate. CONCLUSIONS: Bezafibrate synergized the tumoricidal effect of PD-1 blockade in hyporesponsive lung cancer by expansion of effector CTLs within tumor microenvironment. The potential mechanism may relate to the capacity of bezafibrate in regulating FAO of tumor-infiltrating CTLs.


Assuntos
Neoplasias Pulmonares/etiologia , Neoplasias Pulmonares/metabolismo , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/agonistas , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/metabolismo , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Sinergismo Farmacológico , Ácidos Graxos/metabolismo , Feminino , Humanos , Imunofenotipagem , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/mortalidade , Camundongos , Mitocôndrias/metabolismo , Oxirredução/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Immunology ; 159(2): 193-204, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31631339

RESUMO

Excessive inflammatory immune responses during infections with Plasmodium parasites are responsible for severe complications such as cerebral malaria (CM) that can be studied experimentally in mice. Dendritic cells (DCs) activate cytotoxic CD8+ T-cells and initiate immune responses against the parasites. Batf3-/- mice lack a DC subset, which efficiently induces strong CD8 T-cell responses by cross-presentation of exogenous antigens. Here we show that Batf3-/- mice infected with Plasmodium berghei ANKA (PbA) were protected from experimental CM (ECM), characterized by a stable blood-brain barrier (BBB) and significantly less infiltrated peripheral immune cells in the brain. Importantly, the absence of ECM in Batf3-/- mice correlated with attenuated responses of cytotoxic T-cells, as their parasite-specific lytic activity as well as the production of interferon gamma and granzyme B were significantly decreased. Remarkably, spleens of ECM-protected Batf3-/- mice had elevated levels of regulatory immune cells and interleukin 10. Thus, protection from ECM in PbA-infected Batf3-/- mice was associated with the absence of strong CD8+ T-cell activity and induction of immunoregulatory mediators and cells.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/deficiência , Encéfalo/imunologia , Células Dendríticas/imunologia , Malária Cerebral/prevenção & controle , Plasmodium berghei/patogenicidade , Proteínas Repressoras/deficiência , Linfócitos T Citotóxicos/imunologia , Animais , Fatores de Transcrição de Zíper de Leucina Básica/genética , Barreira Hematoencefálica/imunologia , Barreira Hematoencefálica/parasitologia , Encéfalo/metabolismo , Encéfalo/parasitologia , Células Cultivadas , Células Dendríticas/metabolismo , Células Dendríticas/parasitologia , Modelos Animais de Doenças , Feminino , Granzimas/imunologia , Granzimas/metabolismo , Interações Hospedeiro-Parasita , Interferon gama/imunologia , Interferon gama/metabolismo , Interleucina-10/imunologia , Interleucina-10/metabolismo , Malária Cerebral/imunologia , Malária Cerebral/metabolismo , Malária Cerebral/parasitologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Plasmodium berghei/imunologia , Proteínas Repressoras/genética , Baço/imunologia , Baço/metabolismo , Baço/parasitologia , Linfócitos T Citotóxicos/metabolismo , Linfócitos T Citotóxicos/parasitologia
9.
Carbohydr Polym ; 229: 115457, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31826423

RESUMO

We previously demonstrated that porphyran, a sulfated polysaccharide extracted from Pyropia yezoensis, shows protective effects on LPS-induced septic shock in the mouse. However, the immune cell-mediated inhibitory effect of porphyran in LPS-induced activation of immune cells has not been well investigated. In this study, we found that treatment of porphyran suppressed LPS-induced upregulation of costimulatory molecule and C-C chemokine receptor type 7 (CCR7) expression in bone marrow-derived dendritic cells (BMDCs) in vitro and spleen DCs in vivo. Moreover, the LPS-induced expression of IL-6, IL-12, and TNF-α in the culture medium of BMDCs and serum dose-dependently decreased by porphyran treatment, which contributed to the inhibition of the intracellular cytokine production in spleen DCs. In addition, LPS-induced differentiation of helper T1 (Th1) and cytotoxic T1 (Tc1) cells was effectively suppressed by porphyran treatment in mice. The inhibitory effect of porphyran in LPS-induced immune activation was mediated by competitive binding of porphyran with LPS in spleen DCs. Thus, these results suggest that porphyran is a promising potential therapeutic agent in endotoxin-mediated inflammatory disease and septic shock.


Assuntos
Anti-Inflamatórios/farmacologia , Células Dendríticas/efeitos dos fármacos , Polissacarídeos Bacterianos/farmacologia , Sefarose/análogos & derivados , Animais , Células da Medula Óssea/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Citocinas/metabolismo , Imunidade Celular/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Camundongos Endogâmicos C57BL , Rodófitas/química , Sefarose/farmacologia , Baço/citologia , Linfócitos T Citotóxicos/metabolismo , Células Th1/metabolismo
10.
Nat Commun ; 10(1): 5531, 2019 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-31797935

RESUMO

CD4+ T cell help is required for the generation of CD8+ cytotoxic T lymphocyte (CTL) memory. Here, we use genome-wide analyses to show how CD4+ T cell help delivered during priming promotes memory differentiation of CTLs. Help signals enhance IL-15-dependent maintenance of central memory T (TCM) cells. More importantly, help signals regulate the size and function of the effector memory T (TEM) cell pool. Helped TEM cells produce Granzyme B and IFNγ upon antigen-independent, innate-like recall by IL-12 and IL-18. In addition, helped memory CTLs express the effector program characteristic of helped primary CTLs upon recall with MHC class I-restricted antigens, likely due to epigenetic imprinting and sustained mRNA expression of effector genes. Our data thus indicate that during priming, CD4+ T cell help optimizes CTL memory by creating TEM cells with innate and help-independent antigen-specific recall capacities.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Memória Imunológica/imunologia , Vacinas de DNA/imunologia , Animais , Células Cultivadas , Feminino , Granzimas/imunologia , Granzimas/metabolismo , Antígenos de Histocompatibilidade Classe I/imunologia , Antígenos de Histocompatibilidade Classe I/metabolismo , Interferon gama/imunologia , Interferon gama/metabolismo , Interleucina-12/imunologia , Interleucina-12/metabolismo , Ativação Linfocitária/imunologia , Masculino , Camundongos , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/metabolismo
11.
Nat Commun ; 10(1): 5396, 2019 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-31776337

RESUMO

Killer T cells (cytotoxic T lymphocytes, CTLs) maintain immune homoeostasis by eliminating virus-infected and cancerous cells. CTLs achieve this by forming an immunological synapse with their targets and secreting a pore-forming protein (perforin) and pro-apoptotic serine proteases (granzymes) into the synaptic cleft. Although the CTL and the target cell are both exposed to perforin within the synapse, only the target cell membrane is disrupted, while the CTL is invariably spared. How CTLs escape unscathed remains a mystery. Here, we report that CTLs achieve this via two protective properties of their plasma membrane within the synapse: high lipid order repels perforin and, in addition, exposed phosphatidylserine sequesters and inactivates perforin. The resulting resistance of CTLs to perforin explains their ability to kill target cells in rapid succession and to survive these encounters. Furthermore, these mechanisms imply an unsuspected role for plasma membrane organization in protecting cells from immune attack.


Assuntos
Lipídeos de Membrana/química , Células T Matadoras Naturais/imunologia , Linfócitos T Citotóxicos/metabolismo , Animais , Linfócitos T CD8-Positivos/imunologia , Morte Celular , Linhagem Celular , Membrana Celular/química , Membrana Celular/metabolismo , Colesterol/metabolismo , Lipídeos de Membrana/metabolismo , Camundongos Transgênicos , Perforina/metabolismo , Fosfatidilserinas/metabolismo , Linfócitos T Citotóxicos/química , Linfócitos T Citotóxicos/imunologia
12.
Adv Mater ; 31(52): e1904997, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31721331

RESUMO

Cancer immunotherapy has achieved promising clinical responses in recent years owing to the potential of controlling metastatic disease. However, there is a limited research to prove the superior therapeutic efficacy of immunotherapy on breast cancer compared with melanoma and non-small-cell lung cancer because of its limited expression of PD-L1, low infiltration of cytotoxic T lymphocytes (CTLs), and high level of myeloid-derived suppressor cells (MDSCs). Herein, a multifunctional nanoplatform (FA-CuS/DTX@PEI-PpIX-CpG nanocomposites, denoted as FA-CD@PP-CpG) for synergistic phototherapy (photodynamic therapy (PDT), photothermal therapy (PTT) included) and docetaxel (DTX)-enhanced immunotherapy is successfully developed. The nanocomposites exhibit excellent PDT efficacy and photothermal conversion capability under 650 and 808 nm irradiation, respectively. More significantly, FA-CD@PP-CpG with no obvious side effects can remarkably inhibit the tumor growth in vivo based on a 4T1-tumor-bearing mice modal. A low dosage of loaded DTX in FA-CD@PP-CpG can promote infiltration of CTLs to improve efficacy of anti-PD-L1 antibody (aPD-L1), suppress MDSCs, and effectively polarize MDSCs toward M1 phenotype to reduce tumor burden, further to enhance the antitumor efficacy. Taken together, FA-CD@PP-CpG nanocomposites offer an efficient synergistic therapeutic modality in docetaxel-enhanced immunotherapy for clinical application of breast cancer.


Assuntos
Docetaxel/química , Oligonucleotídeos/química , Linfócitos T Citotóxicos/imunologia , Animais , Anticorpos Monoclonais Humanizados/química , Anticorpos Monoclonais Humanizados/uso terapêutico , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cobre/química , Docetaxel/farmacologia , Docetaxel/uso terapêutico , Portadores de Fármacos/química , Ácido Fólico/química , Humanos , Imunoterapia , Lasers , Camundongos , Nanocompostos/química , Fototerapia , Polietilenoimina/química , Protoporfirinas/química , Espécies Reativas de Oxigênio/metabolismo , Linfócitos T Citotóxicos/citologia , Linfócitos T Citotóxicos/metabolismo , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Neoplasias de Mama Triplo Negativas/terapia
14.
Int J Biol Sci ; 15(9): 1933-1941, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31523194

RESUMO

The prognostic value of programmed death-ligand 1 (PD-L1) has been controversial in recent studies. PD-L1 is known to play a major role in suppressing the immune response, yet increasing studies have reported that PD-L1 expression has a favorable prognostic value for cancer patients. This raises the concern about how to understand PD-L1 expression: merely an immune inhibitory signal, or more likely a reactive process to T-cell response that indicates cytotoxic T lymphocyte (CTL) level in a tumor? To solve this dilemma, an integrative investigation is required. We compared the PD-L1 expression between tumor cells and immune cells, and characterized the inter- and intra-tumor correlation between CTL and PD-L1 expression. The prognostic values between PD-L1 and CTL is compared across 15 solid cancers and 11 independent cohorts of ovarian cancer. PD-L1 and PD-L1-adjusted CTL are analyzed in immunotherapy dataset receiving nivolumab. We observed unexpected high concordance between the prognostic value of PD-L1 and CTL across different cancers and cohorts. We found primarily reactive rather than constitutive PD-L1 expression in most tumors. We revealed that PD-L1-adjusted CTL level, rather than the expression of PD-L1, effectively predicts the responders to immune checkpoint inhibitors. This study highlights the importance of PD-L1 expression, as primarily a signature of reacting efficiency of pre-existing anti-tumor immunity, in balancing the tumor microenvironment. Importantly, it suggests that the reactive efficiency of PD-L1 is more useful to predict the response to immunotherapy.


Assuntos
Antígeno B7-H1/metabolismo , Neoplasias Ovarianas/metabolismo , Antígenos CD8/genética , Antígenos CD8/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Imunoterapia , Técnicas In Vitro , Linfócitos T Citotóxicos/metabolismo
15.
J Cancer Res Clin Oncol ; 145(12): 3055-3065, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31522278

RESUMO

PURPOSE: Combined immunotherapy with anti-programmed cell death-ligand 1 (PD-L1) and an inhibitor of cluster of differentiation 47 (CD47) have exhibited preliminary anti-tumor effect. Our study attempted to describe the PD-L1/CD47 expression status in pulmonary sarcomatoid carcinoma (PSC), and explore its survival impact and relevance with cytotoxic T lymphocytes and macrophages infiltration. METHODS: 148 patients with PSC who underwent surgeries were retrospectively reviewed. Tissue microarrays were conducted for immunohistochemistry (IHC) of PD-L1, CD47, CD8 and CD68. RESULTS: 54 (36.5%) and 78 (52.7%) cases were positive for PD-L1 and CD47, respectively, and 36 (24.3%) of them demonstrated PD-L1/CD47 co-expression. There was a significant correlation between PD-L1 and CD47 expression (P = 0.011). The median overall survival (OS) was 22.5 months (range 0.9-102.4 months). The univariate analysis demonstrated a significantly worse OS in cases with CD47 expression (hazard ratio [HR], 1.66; 95% CI, 1.14-2.42, P = 0.008) and PD-L1/CD47 co-expression (HR, 1.75; 95% CI, 1.15-2.67, P = 0.009). The multivariate analysis demonstrated PD-L1/CD47 co-expression (HR, 1.83; 95% CI, 1.17-2.87, P = 0.008), T stage, M stage, completeness of resection and adjuvant therapy were independent prognostic factors for OS. There was a significant relevance between PD-L1 expression and PD-L1/CD47 co-expression with higher densities of CD8-positive T lymphocytes (P = 0.004, 0.012, respectively) and CD68-positive macrophages (P = 0.026, 0.034, respectively). CONCLUSION: We demonstrated the PD-L1/CD47 co-expression status in PSC. PD-L1 expression correlated with CD47 expression, and PD-L1/CD47 co-expression correlated with poorer prognosis and may serve as a predictive biomarker for combined dual-targeting immunotherapy in PSC patients.


Assuntos
Antígeno B7-H1/metabolismo , Antígeno CD47/metabolismo , Carcinoma/metabolismo , Neoplasias Pulmonares/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/patologia , Carcinoma/patologia , Diferenciação Celular/fisiologia , Feminino , Humanos , Imunoterapia/métodos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias/métodos , Prognóstico , Estudos Retrospectivos , Linfócitos T Citotóxicos/metabolismo , Linfócitos T Citotóxicos/patologia
16.
J Exp Clin Cancer Res ; 38(1): 351, 2019 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-31409352

RESUMO

BACKGROUND: Soluble fibrinogen-like protein 2 (sFGL2), a secretory protein expressed by regulatory T cells (Tregs) with immunosuppressive activity, is highly expressed in both the peripheral blood and tumor tissue of patients with hepatocellular carcinoma (HCC); however, sFGL2 function in HCC remains largely unknown. Here, we elucidated the potential role of sFGL2 in HCC progression. METHODS: T cells, dendritic cells (DCs), and related cytokines in the tumor microenvironment were comparatively analyzed in BALB/c and C57BL/6 mice bearing transplanted hepatomas harboring Fgl2-knockout or receiving sFGL2-antibody treatment. Additionally, the effects of sFGL2 on DCs and T cells were evaluated in vivo and ex vivo. RESULTS: The growth of both subcutaneously and orthotopically transplanted hepatomas was inhibited in Fgl2-knockout mice and those treated with the sFGL2 antibody, respectively, as compared with controls. Moreover, sFGL2 depletion enhanced the proportion and cytotoxicity of cytotoxic T cells, promoted DC maturation, and improved DC activity to proliferate T cells in the tumor microenvironment. Furthermore, we detected lower levels of interleukin (IL)-35 in both types of transplanted hepatomas and higher level of IL-6 in orthotopically transplanted hepatomas following sFGL2 depletion. Mechanistically, we found that sFGL2 impaired bone-marrow-derived DC (BMDCs) function by inhibiting phosphorylation of Akt, nuclear factor-kappaB, cAMP response element binding protein, and p38 and downregulating the expression of major histocompatibility complex II, CD40, CD80, CD86, and CD83 on BMDCs in vitro. CONCLUSIONS: Our data suggest that sFGL2 promotes hepatoma growth by attenuating DC activity and subsequent CD8+ T cell cytotoxicity, suggesting sFGL2 as a novel potential therapeutic target for HCC treatment.


Assuntos
Citotoxicidade Imunológica , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Fibrinogênio/metabolismo , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/metabolismo , Animais , Anticorpos Monoclonais/farmacologia , Biomarcadores , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Citocinas/metabolismo , Citotoxicidade Imunológica/efeitos dos fármacos , Modelos Animais de Doenças , Feminino , Fibrinogênio/antagonistas & inibidores , Fibrinogênio/genética , Fibrinogênio/farmacologia , Xenoenxertos , Humanos , Imunofenotipagem , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Camundongos , Camundongos Knockout , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos
17.
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
18.
Rheumatology (Oxford) ; 58(12): 2325-2329, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31257448

RESUMO

OBJECTIVE: In autoimmune arthritis, TCR signalling is attenuated by peripheral tolerance mechanisms. We have described previously a population of inhibitory receptor LIR-1 expressing autoreactive CD8+ T cells in rheumatoid arthritis. Here, we investigated the role of CD8+ T cells in murine autoimmune arthritis by analysing their expression of the mouse orthologue of LIR-1, PIR-B. METHODS: Frequencies of PIR-B+CD8+ T cells were determined in the SKG arthritis model. The phenotype of those cells was determined ex vivo by FACS and functionality was investigated by means of cytokine production and cytolytic potential upon activation in vitro. RESULTS: SKG mice, under non-SPF (specific pathogen-free) conditions with clinical symptoms of arthritis, were found to harbour significantly increased frequencies of PIR-B+CD8+ T cells. Those cells showed a pro-inflammatory phenotype with preferential production of IL-17 and IFN-γ. The frequency of those cells correlated inversely with the arthritis score, indicating that they might represent autoreactive, but functionally inhibited, CD8+ T cells. CONCLUSION: PIR-B+CD8+ T cells from SKG mice show a cytotoxic and pro-inflammatory phenotype. Inhibition of CD8+ T cell autoreactivity by PIR-B/LIR-1 receptor signalling might be a counter-regulatory mechanism to curb autoreactivity and arthritis.


Assuntos
Artrite Experimental , Artrite Reumatoide/imunologia , Doenças Autoimunes/imunologia , Linfócitos T CD8-Positivos/imunologia , Receptores Imunológicos/biossíntese , Linfócitos T Citotóxicos/imunologia , Animais , Artrite Reumatoide/metabolismo , Artrite Reumatoide/patologia , Doenças Autoimunes/metabolismo , Doenças Autoimunes/patologia , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/patologia , Citometria de Fluxo , Receptor B1 de Leucócitos Semelhante a Imunoglobulina/biossíntese , Glicoproteínas de Membrana , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos DBA , Linfócitos T Citotóxicos/metabolismo , Linfócitos T Citotóxicos/patologia
19.
BMC Cancer ; 19(1): 687, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31307428

RESUMO

BACKGROUND: In a prospective study with long-term follow-up, we analyzed circulating T cell subsets in patients with metastatic colorectal cancer (mCRC) in the context of primary tumor sidedness, KRAS status, and clinical outcome. Our primary goal was to investigate whether baseline levels of circulating T cell subsets serve as a potential biomarker of clinical outcome of mCRC patients treated with an anti-VEGF-based regimen. METHODS: The study group consisted of 36 patients with colorectal adenocarcinoma who started first-line chemotherapy with bevacizumab for metastatic disease. We quantified T cell subsets including Tregs and CD8+ T cells in the peripheral blood prior to therapy initiation. Clinical outcome was evaluated as progression-free survival (PFS), overall survival (OS), and objective response rate (ORR). RESULTS: 1) mCRC patients with KRAS wt tumors had higher proportions of circulating CD8+ cytotoxic T cells among all T cells but also higher measures of T regulatory (Treg) cells such as absolute count and a higher proportion of Tregs in the CD4+ subset. 2) A low proportion of circulating Tregs among CD4+ cells, and a high CD8:Treg ratio at initiation of VEGF-targeting therapy, were associated with favorable clinical outcome. 3) In a subset of patients with primarily right-sided mCRC, superior PFS and OS were observed when the CD8:Treg ratio was high. CONCLUSIONS: The baseline level of circulating immune cells predicts clinical outcome of 1st-line treatment with the anti-VEGF angio/immunomodulatory agent bevacizumab. Circulating immune biomarkers, namely the CD8:Treg ratio, identified patients in the right-sided mCRC subgroup with favorable outcome following treatment with 1st-line anti-VEGF treatment.


Assuntos
Adenocarcinoma/tratamento farmacológico , Inibidores da Angiogênese/uso terapêutico , Bevacizumab/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Metástase Neoplásica/tratamento farmacológico , Linfócitos T Citotóxicos/metabolismo , Linfócitos T Reguladores/metabolismo , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Adenocarcinoma/sangue , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Inibidores da Angiogênese/administração & dosagem , Bevacizumab/administração & dosagem , Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/sangue , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Feminino , Seguimentos , Humanos , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Intervalo Livre de Progressão , Estudos Prospectivos , Proteínas Proto-Oncogênicas p21(ras)/análise , Taxa de Sobrevida
20.
Med Sci Monit ; 25: 4877-4884, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31258152

RESUMO

BACKGROUND CD8+ cytotoxic T lymphocytes (CTLs) have been proved to exert crucial roles in immunological rejection. Exosomes (EXOs) secreted by CD4+CD25+ regulatory T (Treg) cells is believed to be deeply involved in immune regulation. Nevertheless, whether immunomodulatory effect of CD4+CD25+ Treg cells on CD8+ CTL depends on EXOs remains unknown and needs to be explored. MATERIAL AND METHODS We purified CD4+CD25+ Treg cells followed by in vitro amplification. EXOs in culture supernatants of Treg cells was separated and identified. The effect of CD4+CD25+ Treg cells and CD4+CD25+ Treg cells-derived EXOs on CD8+ CTL viability, proliferation, cell cycle mRNA, intracellular cytokines, and protein expression were investigated. RESULTS We successfully obtained EXOs from CD4+CD25+ Treg cells. The inhibition effect of EXOs on CD8+ CTL was concentration-dependent. In addition, the inhibition effect of CD4+CD25+ Treg cells could be reversed by GW4869, an EXOs inhibitor. The inhibition effect was associated with the regulation of IFN-γ and perforin. Our in vivo experiments proved that natural CD4+CD25+ Treg cells-released EXOs can prolong liver allograft survival. CONCLUSIONS CD4+CD25+ Treg cells-derived EXOs could become an alternative tool for manipulating the immune system to discover novel underlying immunomodulatory mechanisms.


Assuntos
Exossomos/metabolismo , Linfócitos T Citotóxicos/metabolismo , Linfócitos T Reguladores/metabolismo , Aloenxertos/imunologia , Animais , Antígenos CD4/imunologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Proliferação de Células/fisiologia , Exossomos/imunologia , Fígado/metabolismo , Transplante de Fígado/métodos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Ratos , Ratos Sprague-Dawley , Ratos Wistar , Linfócitos T Reguladores/imunologia , Tolerância ao Transplante/imunologia
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