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1.
Immunity ; 52(1): 136-150.e6, 2020 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-31940267

RESUMO

Effector CD8+ T cells are important mediators of adaptive immunity, and receptor-ligand interactions that regulate their survival may have therapeutic potential. Here, we identified a subset of effector CD8+ T cells that expressed the inhibitory fragment crystallizable (Fc) receptor FcγRIIB following activation and multiple rounds of division. CD8+ T cell-intrinsic genetic deletion of Fcgr2b increased CD8+ effector T cell accumulation, resulting in accelerated graft rejection and decreased tumor volume in mouse models. Immunoglobulin G (IgG) antibody was not required for FcγRIIB-mediated control of CD8+ T cell immunity, and instead, the immunosuppressive cytokine fibrinogen-like 2 (Fgl2) was a functional ligand for FcγRIIB on CD8+ T cells. Fgl2 induced caspase-3/7-mediated apoptosis in Fcgr2b+, but not Fcgr2b-/-, CD8+ T cells. Increased expression of FcγRIIB correlated with freedom from rejection following withdrawal from immunosuppression in a clinical trial of kidney transplant recipients. Together, these findings demonstrate a cell-intrinsic coinhibitory function of FcγRIIB in regulating CD8+ T cell immunity.


Assuntos
Apoptose/imunologia , Linfócitos T CD8-Positivos/imunologia , Fibrinogênio/imunologia , Receptores de IgG/imunologia , Adulto , Idoso , Animais , Caspase 3/imunologia , Caspase 7/imunologia , Linhagem Celular Tumoral , Feminino , Fibrinogênio/genética , Rejeição de Enxerto/imunologia , Humanos , Imunoglobulina G/imunologia , Imunossupressão , Masculino , Melanoma Experimental , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Receptores de IgG/genética , Adulto Jovem
2.
Immunity ; 52(1): 123-135.e6, 2020 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-31859049

RESUMO

The immune system monitors the health of cells and is stimulated by necrosis. Here we examined the receptors and ligands driving this response. In a targeted screen of C-type lectin receptors, a Clec2d reporter responded to lysates from necrotic cells. Biochemical purification identified histones, both free and bound to nucleosomes or neutrophil extracellular traps, as Clec2d ligands. Clec2d recognized poly-basic sequences in histone tails and this recognition was sensitive to post-translational modifications of these sequences. As compared with WT mice, Clec2d-/- mice exhibited reduced proinflammatory responses to injected histones, and less tissue damage and improved survival in a hepatotoxic injury model. In macrophages, Clec2d localized to the plasma membrane and endosomes. Histone binding to Clec2d did not stimulate kinase activation or cytokine production. Rather, histone-bound DNA stimulated endosomal Tlr9-dependent responses in a Clec2d-dependent manner. Thus, Clec2d binds to histones released upon necrotic cell death, with functional consequences to inflammation and tissue damage.


Assuntos
Histonas/metabolismo , Lectinas Tipo C/imunologia , Lectinas Tipo C/metabolismo , Fígado/lesões , Necrose/patologia , Receptores de Superfície Celular/imunologia , Receptores de Superfície Celular/metabolismo , Animais , Apoptose/imunologia , Endossomos/metabolismo , Células HEK293 , Humanos , Células Jurkat , Lectinas Tipo C/genética , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neutrófilos/imunologia , Receptores de Superfície Celular/genética , Receptor Toll-Like 9/imunologia
3.
J Environ Pathol Toxicol Oncol ; 38(3): 239-251, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31679311

RESUMO

Fucoxanthin, a potent carotenoid present in various natural sources especially from seaweeds; it exhibits several biological effects like anti-neoplastic, anti-mutagenic, anti-diabetic, anti-obesity and anti-inflammatory actions. Fucoxanthin role in chemoprevention of lung cancer in mouse model induced using benzo(a)pyrene [B(a)P] has been presented here. Oral administration of fucoxanthin with and without B(a)P were studied, the results from our study shows that fucoxanthin significantly decreased tumor progression in mice exposed to B(a)P, the obtained data were correlated with increased antioxidant, apoptosis and decreased tumour marker and anti-apoptotic molecules. With respect to apoptosis, fucoxanthin treated animals shows increased apoptosis compared to tumor induced mice by increased expression of caspase 9 and 3 and decreased expression of anti-apoptotic Bcl2 protein. Finally, histopathological and immuno histochemical analysis also revealed that fucoxanthin shows potent anticancer agent by bringing back the damaged tissue treated with B(a)P and also decreases the expression of PCNA in cancer induced mice. The anticancer effect of fucoxanthin may be attributed by several independent mechanisms which play a important roles in the prevention of cancer development, there is also substantial evidences to show that fucoxanthin acts indirectly by increasing the antioxidant capacity of affected tissue and prepared to cope up with oxidative stress which is proved in our study. Thus from our study it is clearly established that fucoxanthin act as a persuasive anticancer drug against lung cancer.


Assuntos
Anti-Inflamatórios/farmacologia , Apoptose/imunologia , Inflamação/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Transdução de Sinais/imunologia , Xantofilas/farmacologia , Animais , Antioxidantes/metabolismo , Apoptose/efeitos dos fármacos , Benzo(a)pireno/toxicidade , Inflamação/induzido quimicamente , Masculino , Camundongos , Transdução de Sinais/efeitos dos fármacos
4.
Biochimie ; 167: 135-144, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31585151

RESUMO

Glycosylphosphatidylinositols (GPIs) are glycolipids described as toxins of protozoan parasites due to their inflammatory properties in mammalian hosts characterized by the production of interleukin (IL)-1, IL-12 and tumor necrosis factor (TNF)-α. In the present work, we studied the cytokines produced by antigen presenting cells in response to ten different GPI species extracted from Babesia divergens, responsible for babesiosis. Interestingly, B. divergens GPIs induced the production of anti-inflammatory cytokines (IL-2, IL-5) and of the regulatory cytokine IL-10 by macrophages and dendritic cells. In contrast to all protozoan GPIs studied until now, GPIs from B. divergens did not stimulate the production of TNF-α and IL-12, leading to a unique Th1/Th2 profile. Analysis of the carbohydrate composition of the B. divergens GPIs indicated that the di-mannose structure was different from the evolutionary conserved tri-mannose structure, which might explain the particular cytokine profile they induce. Expression of major histocompatibility complex (MHC) molecules on dendritic cells and apoptosis of mouse peritoneal cells were also analysed. B. divergens GPIs did not change expression of MHC class I, but decreased expression of MHC class II at the cell surface, while GPIs slightly increased the percentages of apoptotic cells. During pathogenesis of babesiosis, the inflammation-coagulation auto-amplification loop can lead to thrombosis and the effect of GPIs on coagulation parameters was investigated. Incubation of B. divergens GPIs with rat plasma ex vivo led to increase of fibrinogen levels and to prolonged activated partial thromboplastin time, suggesting a direct modulation of the extrinsic coagulation pathway by GPIs.


Assuntos
Antígenos de Protozoários/imunologia , Babesia/imunologia , Citocinas/imunologia , Células Dendríticas/imunologia , Glicosilfosfatidilinositóis/imunologia , Macrófagos/imunologia , Animais , Apoptose/imunologia , Babesiose/sangue , Coagulação Sanguínea , Complexo Principal de Histocompatibilidade/imunologia , Camundongos , Ratos , Ratos Wistar
5.
J Exp Clin Cancer Res ; 38(1): 355, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31412896

RESUMO

BACKGROUND: Human epidermal growth factor receptor 2 (HER2) is overexpressed in multiple cancers, which is associated with poor prognosis. Herceptin and other agents targeting HER2 have potent antitumor efficacy in patients with HER2-positive cancers. However, the development of drug resistance adversely impacts the efficacy of these treatments. It is therefore urgent to develop new HER2-targeted therapies. Bispecific antibodies (BsAbs) could guide immune cells toward tumor cells, and produced remarkable effects in some cancers. METHODS: A BsAb named M802 that targets HER2 and CD3 was produced by introducing a salt bridge and knobs-into-holes (KIHs) packing into the structure. Flow cytometry was performed to determine its binding activity and cytotoxicity. CCK-8, Annexin V/PI staining, western blotting, and ELISA were utilized to study its effect on cell proliferation, apoptosis, the signaling pathways of tumor cells, and the secretion of cytokines by immune cells. Subcutaneous tumor mouse models were used to analyze the in vivo antitumor effects of M802. RESULTS: We generated a new format of BsAb, M802, consisting of a monovalent unit against HER2 and a single chain unit against CD3. Our in vitro and in vivo experiments indicated that M802 recruited CD3-positive immune cells and was more cytotoxic than Herceptin in cells with high expression of HER2, low expression of HER2, and Herceptin resistance. Although M802 showed weaker effects than Herceptin on the PI3K/AKT and MAPK pathways, it was more cytotoxic due to its specific recognition of HER2 and its ability to recruit effector cells via its anti-CD3 moiety. CONCLUSIONS: Our results indicated that M802 exhibited potent antitumor efficacy in vitro and in vivo. M802 retained the function of Herceptin in antitumor signaling pathways, and also recruited CD3-positive immune cells to eliminate HER2-positive tumor cells. Therefore, M802 might be a promising HER2 targeted agent.


Assuntos
Anticorpos Biespecíficos/farmacologia , Antineoplásicos Imunológicos/farmacologia , Complexo CD3/antagonistas & inibidores , Receptor ErbB-2/antagonistas & inibidores , Animais , Anticorpos Biespecíficos/química , Antineoplásicos Imunológicos/química , Apoptose/efeitos dos fármacos , Apoptose/imunologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/imunologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Citocinas/metabolismo , Citotoxicidade Imunológica/efeitos dos fármacos , Modelos Animais de Doenças , Humanos , Ativação Linfocitária/efeitos dos fármacos , Ativação Linfocitária/imunologia , Melanoma Experimental , Camundongos , Peso Molecular , Transdução de Sinais/efeitos dos fármacos , Análise Espectral , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Linfócitos T/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Lupus ; 28(10): 1214-1223, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31399013

RESUMO

OBJECTIVE: The aim of this study was to evaluate the changes in CD8+CD28-/CD8+CD28+ T-cell subset balance and in the CD8+CD28- Treg cell number and function in patients with systemic lupus erythematosus (SLE). METHODS: Cell isolation and flow cytometry analysis were employed to investigate the T-cell subsets. RESULTS: It was found that in high-activity SLE patients, the CD8+CD28+ T-cell subset was reduced, which was inversely correlated with the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI), and that the CD8+CD28-/CD8+CD28+ ratio was elevated, which was positively correlated with SLEDAI and with renal damage and inversely correlated with serum complement level, whereas the CD8+CD28- T-cell subset was increased only in inactive patients. It was also found that apoptosis of CD8+ T cells increased, and Fas, Fas ligand (FasL) and interleukin (IL)-6 expression were high, whereas cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) expression was low by the CD8+CD28+ T cell subset in active SLE patients; apoptosis was positively correlated with SLEDAI and with the expression of Fas and FasL by the CD8+CD28+ T-cell subset in active SLE patients. IL-6 and CTLA-4 expression were found to be low by the CD8+CD28- T cell subset in active SLE patients. CONCLUSION: These data suggest that high expression of Fas, FasL and IL-6 and low expression of CTLA-4 by the CD8+CD28+ T-cell subset promotes the activation-induced cell death of the CD8+CD28+ T-cell subset, resulting in an imbalance of CD8+CD28-/CD8+CD28+ T cells in active SLE patients, which represents an important feature in the immunological pathogenesis of SLE. The CD8+CD28- T-cell subset may play some role in inactive SLE.


Assuntos
Antígenos CD28/imunologia , Linfócitos T CD8-Positivos/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Adulto , Idoso , Apoptose/imunologia , Estudos de Casos e Controles , Feminino , Citometria de Fluxo , Humanos , Masculino , Pessoa de Meia-Idade , Subpopulações de Linfócitos T/imunologia , Linfócitos T Reguladores/imunologia , Adulto Jovem
7.
Fish Shellfish Immunol ; 93: 958-964, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31442589

RESUMO

The protozoan parasite Bonamia ostreae has been associated with the decline of flat oyster Ostrea edulis populations in some European countries. Control of shellfish diseases mostly relies on prevention measures including transfer restrictions and stock management measures such as breeding programmes. These prevention and mitigation measures require a better understanding of interactions between host and pathogens. Previous in vitro studies allowed identifying apoptosis as a mechanism activated by the flat oyster in response to B. ostreae. However, these experiments also suggested that the parasite is able to regulate apoptosis in order to survive and multiply within hemocytes. By simplifying the conditions of infection, in vitro studies allow identifying most distinct features of the response of the host. In order to appreciate the relative importance of apoptosis in this response at the oyster scale, in vivo trials were carried out by injecting with parasites oysters from two French locations, Quiberon Bay (Brittany) and Diana Lagoon (Corsica). Apoptosis was investigated on pools of hemolymph from oysters collected at early and later times after injection using previously developed tools. Apoptotic cellular activities including intracytoplasmic calcium concentration, mitochondrial membrane potential and phosphatidyl serine externalization were analysed using flow cytometry. Moreover, the expression of flat oyster genes involved in both extrinsic and intrinsic pathways was measured using real time quantitative PCR.


Assuntos
Apoptose/imunologia , Haplosporídios/fisiologia , Interações Hospedeiro-Parasita/imunologia , Ostrea/imunologia , Animais , Citometria de Fluxo , França , Ostrea/parasitologia
8.
Mol Immunol ; 114: 314-322, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31442915

RESUMO

Hematopoietic development occurs in the bone marrow, and this process begins with hematopoietic stem cells (HSCs). Ubc9 is a unique E2-conjugating enzyme required for SUMOylation, an evolutionarily conserved post-translational modification system. We herein show that a conditional Ubc9 deletion in the hematopoietic system caused decreased thymus weight and reduced lymphocyte to myeloid cell ratio. Importantly, Ubc9 deletion in the hematopoietic system only selectively impaired the development of common lymphoid progenitors (CLPs) in the bone marrow and perturbed their potential to differentiate into lymphocytes, thereby decreasing the number of T/B cells in the periphery. Ubc9 was found to be required for CLP viability, and therefore, Ubc9 deficiency rendered CLPs to undergo apoptosis and attenuated their proliferation. Thus, Ubc9 plays a critical role in the regulation of CLP function during hematopoietic development in the bone marrow.


Assuntos
Medula Óssea/imunologia , Hematopoese/imunologia , Células-Tronco Hematopoéticas/imunologia , Enzimas de Conjugação de Ubiquitina/deficiência , Enzimas de Conjugação de Ubiquitina/imunologia , Animais , Apoptose/imunologia , Linfócitos B/imunologia , Diferenciação Celular/imunologia , Linhagem da Célula/imunologia , Masculino , Camundongos , Células Progenitoras Mieloides/imunologia , Linfócitos T/imunologia
9.
Biomed Pharmacother ; 117: 109167, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31387180

RESUMO

Hedyotis diffusa is a well-known traditional Chinese herbal medicine. The polysaccharides extracted from H. diffusa (HDP) exhibit a range of pharmacological activities. Transfusion of cytokine-induced killer (CIK) cell is one type of adoptive cellular immunotherapy, which is becoming an important method of cancer immunotherapy. In this present study, we investigate the immunostimulatory effect of HDP on CIK cells. CIK cells were generated by culturing and stimulating peripheral blood monocytes of healthy volunteers. They were treated with HDP at three different concentrations (10, 50, and 100 µg/mL). The effect of HDP on CIK cell populations, intracellular cytokine production, and apoptosis was examined by flow cytometry. The antitumor effect of HDP on CIK cells was determined by cytotoxicity assay. Furthermore, the effect of HDP on the antitumor activity of CIK cells in a mouse model was investigated. HDP increased the percentage of CD3+CD56+ CIK cells but did not significantly change the percentage of CD4+, CD8+, or CD4+CD25+ CIK cells. The HDP-treated CIK cells showed a greater ability to kill tumor cells, as well as higher production of interferon-γ and tumor necrosis factor-α, compared with the no-HDP-treated CIK cells. The HDP-treated CIK cells also found a lower apoptosis level in vitro. Moreover, HDP combined with CIK cells had a stronger inhibitory effect on tumor growth in the mouse model compared with the CIK or HDP treatment alone. In conclusion, the results indicated that HDP enhanced the antitumor activity of CIK cells and could be used for cancer immunotherapy combined with CIK cell therapy.


Assuntos
Antineoplásicos/farmacologia , Células Matadoras Induzidas por Citocinas/efeitos dos fármacos , Células Matadoras Induzidas por Citocinas/imunologia , Hedyotis/química , Polissacarídeos/imunologia , Polissacarídeos/farmacologia , Células A549 , Animais , Apoptose/efeitos dos fármacos , Apoptose/imunologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Antígeno CD56/imunologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Linhagem Celular Tumoral , Citotoxicidade Imunológica/efeitos dos fármacos , Citotoxicidade Imunológica/imunologia , Células HCT116 , Humanos , Imunoterapia Adotiva/métodos , Interferon gama/imunologia , Subunidade alfa de Receptor de Interleucina-2/imunologia , Células MCF-7 , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Fator de Necrose Tumoral alfa/imunologia
10.
Gastroenterology ; 157(6): 1572-1583.e8, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31470007

RESUMO

BACKGROUND & AIMS: Transgenic mice (HBUS) that express the epidermal growth factor receptor (EGFR) ligand HBEGF (heparin-binding epidermal growth factor-like growth factor) and a constitutively active G protein-coupled receptor (US28) in intestinal epithelial cells develop serrated polyps in the cecum. Development of serrated polyps depends on the composition of the gut microbiota and is associated with bacterial invasion of the lamina propria, accompanied by induction of inflammation and up-regulation of interleukin 1 beta (IL1B) and matrix metalloproteinase (MMP) 3 in the cecum. We investigated the mechanisms by which these changes contribute to development of serrated polyps. METHODS: We performed studies with C57BL/6 (control) and HBUS mice. To accelerate polyp development, we increased the exposure of the bacteria to the lamina propria by injecting HBUS mice with diphtheria toxin, which binds transgenic HBEGF expressed by the epithelial cells and causes apoptosis. Mice were given injections of IL1B-neutralizing antibody and the MMP inhibitor N-isobutyl-N-(4-methoxyphenylsulfonyl)glycyl hydroxamic acid. Intestinal tissues were collected from mice and analyzed by histology, reverse-transcription polymerase chain reaction, enzyme-linked immunosorbent assay, immunofluorescence, and flow cytometry. We examined fibroblast subsets in polyps using single-cell RNA sequencing. RESULTS: Administration of diphtheria toxin to HBUS mice accelerated development of serrated polyps (95% of treated mice developed polyps before 100 days of age, compared with 53% given vehicle). IL1B stimulated subsets of platelet-derived growth factor receptor alpha+ (PDGRFA+) fibroblasts isolated from cecum, resulting in increased expression of MMP3. Neutralizing antibodies against IL1B or administration of the MMP inhibitor reduced the number of serrated polyps that formed in the HBUS mice. Single-cell RNA sequencing analysis showed subsets of fibroblasts in serrated polyps that express genes that regulate matrix fibroblasts and inflammation. CONCLUSIONS: In studies of mice, we found that barrier breakdown and expression of inflammatory factors contribute to development of serrated polyps. Subsets of cecal PDGFRA+ fibroblasts are activated by release of IL1B from myeloid cells during the early stages of serrated polyp development. MMP3 produced by PDGFRA+ fibroblasts is important for serrated polyp development. Our findings confirm the functions of previously identified serrated polyp-associated molecules and indicate roles for immune and stromal cells in serrated polyp development.


Assuntos
Pólipos do Colo/imunologia , Receptores ErbB/metabolismo , Interleucina-1beta/metabolismo , Mucosa Intestinal/patologia , Metaloproteinase 3 da Matriz/metabolismo , Animais , Apoptose/imunologia , Ceco/citologia , Ceco/imunologia , Ceco/patologia , Toxina Diftérica/administração & dosagem , Toxina Diftérica/imunologia , Modelos Animais de Doenças , Células Epiteliais/imunologia , Células Epiteliais/patologia , Receptores ErbB/antagonistas & inibidores , Fibroblastos/imunologia , Fibroblastos/metabolismo , Gefitinibe/farmacologia , Fator de Crescimento Semelhante a EGF de Ligação à Heparina/genética , Fator de Crescimento Semelhante a EGF de Ligação à Heparina/metabolismo , Humanos , Ácidos Hidroxâmicos/farmacologia , Interleucina-1beta/imunologia , Mucosa Intestinal/citologia , Mucosa Intestinal/imunologia , Metaloproteinase 3 da Matriz/imunologia , Inibidores de Metaloproteinases de Matriz/farmacologia , Camundongos , Camundongos Transgênicos , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Sulfonamidas/farmacologia
11.
Nat Commun ; 10(1): 3471, 2019 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-31375662

RESUMO

The uptake of apoptotic polymorphonuclear cells (PMN) by macrophages is critical for timely resolution of inflammation. High-burden uptake of apoptotic cells is associated with loss of phagocytosis in resolution phase macrophages. Here, using a transcriptomic analysis of macrophage subsets, we show that non-phagocytic resolution phase macrophages express a distinct IFN-ß-related gene signature in mice. We also report elevated levels of IFN-ß in peritoneal and broncho-alveolar exudates in mice during the resolution of peritonitis and pneumonia, respectively. Elimination of endogenous IFN-ß impairs, whereas treatment with exogenous IFN-ß enhances, bacterial clearance, PMN apoptosis, efferocytosis and macrophage reprogramming. STAT3 signalling in response to IFN-ß promotes apoptosis of human PMNs. Finally, uptake of apoptotic cells promotes loss of phagocytic capacity in macrophages alongside decreased surface expression of efferocytic receptors in vivo. Collectively, these results identify IFN-ß produced by resolution phase macrophages as an effector cytokine in resolving bacterial inflammation.


Assuntos
Interferon beta/metabolismo , Macrófagos/imunologia , Peritonite/imunologia , Pneumonia Bacteriana/imunologia , Adulto , Idoso , Animais , Apoptose/imunologia , Modelos Animais de Doenças , Escherichia coli/imunologia , Feminino , Perfilação da Expressão Gênica , Humanos , Interferon beta/genética , Interferon beta/imunologia , Células Jurkat , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Knockout , Pessoa de Meia-Idade , Neutrófilos , Pneumonia Bacteriana/microbiologia , Cultura Primária de Células , Fator de Transcrição STAT3/imunologia , Fator de Transcrição STAT3/metabolismo
12.
Nat Commun ; 10(1): 3495, 2019 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-31375697

RESUMO

Immune tolerance to allografts has been pursued for decades as an important goal in transplantation. Administration of apoptotic donor splenocytes effectively induces antigen-specific tolerance to allografts in murine studies. Here we show that two peritransplant infusions of apoptotic donor leukocytes under short-term immunotherapy with antagonistic anti-CD40 antibody 2C10R4, rapamycin, soluble tumor necrosis factor receptor and anti-interleukin 6 receptor antibody induce long-term (≥1 year) tolerance to islet allografts in 5 of 5 nonsensitized, MHC class I-disparate, and one MHC class II DRB allele-matched rhesus macaques. Tolerance in our preclinical model is associated with a regulatory network, involving antigen-specific Tr1 cells exhibiting a distinct transcriptome and indirect specificity for matched MHC class II and mismatched class I peptides. Apoptotic donor leukocyte infusions warrant continued investigation as a cellular, nonchimeric and translatable method for inducing antigen-specific tolerance in transplantation.


Assuntos
Rejeição de Enxerto/prevenção & controle , Sobrevivência de Enxerto/imunologia , Tolerância Imunológica , Transplante das Ilhotas Pancreáticas/efeitos adversos , Linfócitos T Reguladores/transplante , Transferência Adotiva , Aloenxertos/imunologia , Animais , Apoptose/imunologia , Modelos Animais de Doenças , Feminino , Rejeição de Enxerto/imunologia , Humanos , Imunossupressores/uso terapêutico , Ilhotas Pancreáticas/imunologia , Macaca mulatta , Masculino , Linfócitos T Reguladores/imunologia , Doadores de Tecidos , Transplante Homólogo/efeitos adversos
13.
PLoS Comput Biol ; 15(7): e1007172, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31365522

RESUMO

In an inflammatory setting, macrophages can be polarized to an inflammatory M1 phenotype or to an anti-inflammatory M2 phenotype, as well as existing on a spectrum between these two extremes. Dysfunction of this phenotypic switch can result in a population imbalance that leads to chronic wounds or disease due to unresolved inflammation. Therapeutic interventions that target macrophages have therefore been proposed and implemented in diseases that feature chronic inflammation such as diabetes mellitus and atherosclerosis. We have developed a model for the sequential influx of immune cells in the peritoneal cavity in response to a bacterial stimulus that includes macrophage polarization, with the simplifying assumption that macrophages can be classified as M1 or M2. With this model, we were able to reproduce the expected timing of sequential influx of immune cells and mediators in a general inflammatory setting. We then fit this model to in vivo experimental data obtained from a mouse peritonitis model of inflammation, which is widely used to evaluate endogenous processes in response to an inflammatory stimulus. Model robustness is explored with local structural and practical identifiability of the proposed model a posteriori. Additionally, we perform sensitivity analysis that identifies the population of apoptotic neutrophils as a key driver of the inflammatory process. Finally, we simulate a selection of proposed therapies including points of intervention in the case of delayed neutrophil apoptosis, which our model predicts will result in a sustained inflammatory response. Our model can therefore provide hypothesis testing for therapeutic interventions that target macrophage phenotype and predict outcomes to be validated by subsequent experimentation.


Assuntos
Inflamação/imunologia , Macrófagos/imunologia , Modelos Imunológicos , Animais , Apoptose/imunologia , Biologia Computacional , Simulação por Computador , Modelos Animais de Doenças , Humanos , Mediadores da Inflamação/imunologia , Ativação de Macrófagos , Macrófagos/classificação , Macrófagos Peritoneais/classificação , Macrófagos Peritoneais/imunologia , Camundongos , Neutrófilos/citologia , Neutrófilos/imunologia , Fenótipo
14.
Int J Mol Sci ; 20(14)2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31319491

RESUMO

Notch is an evolutionarily conserved signaling family which iteratively exerts pleiotropic functions in cell fate decisions and various physiological processes, not only during embryonic development but also throughout adult life. In the context of the respiratory system, Notch has been shown to regulate ciliated versus secretory lineage differentiation of epithelial progenitor cells and coordinate morphogenesis of the developing lung. Reminiscent of its role in development, the Notch signaling pathway also plays a role in repair of lung injuries by regulation of stem cell activity, cell differentiation, cell proliferation and apoptosis. In addition to functions in embryonic development, cell and tissue renewal and various physiological processes, including glucose and lipid metabolism, Notch signaling has been demonstrated to regulate differentiation of literally almost all T-cell subsets, and impact on elicitation of inflammatory response and its outcome. We have investigated the role of Notch in allergic airway inflammation in both acute and chronic settings. In this mini-review, we will summarize our own work and recent advances on the role of Notch signaling in allergic airway inflammation, and discuss potential applications of the Notch signaling family in therapy for allergic airway diseases.


Assuntos
Asma/imunologia , Receptores Notch/imunologia , Transdução de Sinais/imunologia , Células-Tronco/imunologia , Linfócitos T/imunologia , Animais , Apoptose/imunologia , Asma/patologia , Proliferação de Células , Humanos , Inflamação/imunologia , Inflamação/patologia , Células-Tronco/patologia , Linfócitos T/patologia
15.
Fish Shellfish Immunol ; 92: 889-896, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31299465

RESUMO

Ranaviruses belong to the family Iridoviridae, and have become a serious threat to both farmed and natural populations of fish and amphibians. Previous reports showed that ranaviruses could encode viral Bcl-2 family-like proteins (vBcl-2), which play a critical role in the regulation of cell apoptosis. However, the mechanism of ranaviruses vBcl-2 interactions with host protein in mediating apoptosis remains unknown. Tiger frog virus (TFV) belonging to the genus Ranavirus has been isolated from infected tadpoles of Rana tigrina rugulosa, and it causes a high mortality rate among tiger frog tadpoles cultured in southern China. This study elucidated the molecular mechanism underlying the interaction of TFV ORF104R with the VDAC2 protein to regulate cell apoptosis. TFV ORF104R is highly similar to other ranaviruses vBcl-2 and host Mcl-1 proteins, indicating that TFV ORF104R is a postulate vBcl-2 protein. Transcription and protein expression levels showed that TFV orf104r was a late viral gene. Western blot results suggested that TFV ORF104R was a viral structural protein. Subcellular localization analysis indicated that TFV ORF104R was predominantly colocalized with the mitochondria. Overexpressed TFV ORF104R could suppress the release of cytochrome C and the activities of caspase-9 and caspase-3. These results indicated that TFV ORF104R might play an important role in anti-apoptosis. Furthermore, the interaction between TFV ORF104R and VDAC2 was detected by co-immunoprecipitation in vitro. The above observations suggest that the molecular mechanism of TFV-regulated anti-apoptosis is through the interaction of TFV ORF104R with the VDAC2 protein. Our study provided a mechanistic basis for the ranaviruses vBcl-2-mediated inhibition of apoptosis and improved the understanding on how TFV subverts host defense mechanisms in vivo.


Assuntos
Apoptose/imunologia , Cyprinidae , Infecções por Vírus de DNA/veterinária , Doenças dos Peixes/imunologia , Genes Virais , Ranavirus/fisiologia , Canal de Ânion 2 Dependente de Voltagem/imunologia , Animais , Infecções por Vírus de DNA/imunologia , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Fases de Leitura Aberta , Canal de Ânion 2 Dependente de Voltagem/genética
16.
Mol Immunol ; 112: 188-197, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31176198

RESUMO

Rheumatoid arthritis (RA) is a chronic, systemic, synovitis-based inflammatory disease with unknown etiology. Neutrophils play important roles in the pathogenesis of RA. Apoptosis and NETosis of neutrophils are two major mechanisms of programmed cell death that differ in their morphological characteristics and effects on the immune system. In rheumatoid arthritis, delayed neutrophil apoptosis amplifies the inflammatory response; and massive release of NETs and their components may cause tissue damage and provide self-antigens. Emodin is a natural anthraquinone derivative that occurs in many widely used Chinese medicinal herbs. In this study, we evaluated the effect of emodin on a murine adjuvant-induced arthritis (AA) model of RA in vivo and on neutrophil apoptosis and NETosis in vitro. Our results show that emodin alleviated AA by reducing neutrophil infiltration and proinflammatory cytokine (interleukin-6, interferon-gamma and tumor necrosis factor-α) release. Emodin promoted apoptosis and inhibited autophagy and NETosis in neutrophils. These findings indicate that emodin represents a potential therapeutic agent for RA.


Assuntos
Apoptose/imunologia , Artrite Reumatoide/imunologia , Emodina/imunologia , Armadilhas Extracelulares/imunologia , Infiltração de Neutrófilos/imunologia , Neutrófilos/imunologia , Animais , Artrite Experimental/imunologia , Autoantígenos/imunologia , Autofagia/imunologia , Citocinas/imunologia , Modelos Animais de Doenças , Feminino , Interleucina-6/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fator de Necrose Tumoral alfa/imunologia
17.
Nat Commun ; 10(1): 2603, 2019 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-31197149

RESUMO

During thymic negative selection, autoreactive thymocytes carrying T cell receptor (TCR) with overtly strong affinity to self-MHC/self-peptide are removed by Bim-dependent apoptosis, but how Bim is specifically regulated to link TCR activation and apoptosis induction is unclear. Here we identify a murine T cell-specific genomic enhancer EBAB (Bub1-Acoxl-Bim), whose deletion leads to accumulation of thymocytes expressing high affinity TCRs. Consistently, EBAB knockout mice have defective negative selection and fail to delete autoreactive thymocytes in various settings, with this defect accompanied by reduced Bim expression and apoptosis induction. By contrast, EBAB is dispensable for maintaining peripheral T cell homeostasis via Bim-dependent pathways. Our data thus implicate EBAB as an important, developmental stage-specific regulator of Bim expression and apoptosis induction to enforce thymic negative selection and suppress autoimmunity. Our study unravels a part of genomic enhancer codes that underlie complex and context-dependent gene regulation in TCR signaling.


Assuntos
Autoimunidade/genética , Proteína 11 Semelhante a Bcl-2/genética , Elementos Facilitadores Genéticos/imunologia , Receptores de Antígenos de Linfócitos T/metabolismo , Timócitos/fisiologia , Animais , Apoptose/genética , Apoptose/imunologia , Autoimunidade/imunologia , Proteína 11 Semelhante a Bcl-2/metabolismo , Sistemas CRISPR-Cas/genética , Elementos Facilitadores Genéticos/genética , Feminino , Regulação da Expressão Gênica/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Modelos Animais , Receptores de Antígenos de Linfócitos T/imunologia , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Timo/citologia , Timo/imunologia
18.
J Exp Clin Cancer Res ; 38(1): 262, 2019 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-31200739

RESUMO

Autophagy is a catabolic process whose activation may help cancer cells to adapt to cellular stress although, in some instances, it can induce cell death. Autophagy stimulation or inhibition has been considered an opportunity to treat cancer, especially in combination with anticancer therapies, although autophagy manipulation may be viewed as controversial. Thus, whether to induce or to inhibit autophagy may be the best option in the different cancer patients is still matter of debate. Her we will recapitulate the possible advantages or disadvantages of manipulating autophagy in cancer, not only with the aim to obtain cancer cell death and disable oncogenes, but also to evaluate its interplay with the immune response which is fundamental for the success of anticancer therapies.


Assuntos
Antineoplásicos/uso terapêutico , Autofagia/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Neoplasias/etiologia , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/genética , Apoptose/imunologia , Autofagia/genética , Autofagia/imunologia , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Terapia de Alvo Molecular , Neoplasias/metabolismo , Oncogenes , Transdução de Sinais/efeitos dos fármacos , Resposta a Proteínas não Dobradas
19.
Mol Immunol ; 112: 312-321, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31229844

RESUMO

Precise glycosylation plays a crucial and distinctive role in thymic T cell development. The core fucosylation is dramatically up-regulated at the transition from CD4-CD8- (DN) to CD4+CD8+ (DP) in the thymic development. Ablation of core fucosylation in T cells did reduce the size of the thymus due to a significant loss of CD4+ SP, CD8+ SP and DP thymocytes in core fucosyltransferase (Fut8) knockout (Fut8-/-) mice. T cell receptors (TCRs) are heavily core fucosylated glycoproteins. Loss of core fucosylation of TCR contributed to the reduced phosphorylation of ZAP70 (pZAP70) in Fut8-/- DP cells was observed. Compare to the Fut8+/+OT-II DP thymocytes, pZAP70 was significantly reduced in Fut8-/- OT-II DP thymocytes with OVA323-339 stimulation. Also, the pZAP70 of Fut8+/+OT-I DP thymocytes with OVA257-264 stimulation was remarkably attenuated by treatment of the fucosidase. Upon anti-CD3/CD28 Abs stimulation, the increased apoptosis was found in Fut8-/- thymocytes compared with Fut8+/+ thymocytes. Moreover, the TCRhiCD69hi (post-positive selection thymocytes) was markedly depleted in the Fut8-/- thymus without any stimulation. The expression of CD5 was significantly down-regulated on the DP cells in the Fut8-/- thymus. Our results therefore demonstrate that ablation of core fucosylation results in the abnormal T cell development due to the attenuated signaling via TCR.


Assuntos
Fucose/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Transdução de Sinais/imunologia , Linfócitos T/imunologia , Animais , Antígenos CD/imunologia , Antígenos de Diferenciação de Linfócitos T/imunologia , Apoptose/imunologia , Antígenos CD5/imunologia , Diferenciação Celular/imunologia , Fucosiltransferases/imunologia , Glicosilação , Lectinas Tipo C/imunologia , Ativação Linfocitária/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação/imunologia , Timócitos/imunologia , Proteína-Tirosina Quinase ZAP-70/imunologia
20.
Cancer Sci ; 110(9): 2690-2699, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31250942

RESUMO

Senescence is a state of growth arrest induced not only in normal cells but also in cancer cells by aging or stress, which triggers DNA damage. Despite growth suppression, senescent cancer cells promote tumor formation and recurrence by producing cytokines and growth factors; this state is designated as the senescence-associated secretory phenotype. In this study, we examined the susceptibility of senescent human breast cancer cells to immune cell-mediated cytotoxicity. Doxorubicin (DXR) treatment induced senescence in 2 human breast cancer cell lines, MDA-MB-231 and BT-549, with the induction of γH2AX expression and increased expression of p21 or p16. Treatment with DXR also induced the expression of senescence-associated ß-galactosidase and promoted the production of pro-inflammatory cytokines. Importantly, DXR-treated senescent MDA-MB-231 cells showed increased sensitivity to 2 types of immune cell-mediated cytotoxicity: cytotoxicity of activated CD4+ T cells and Ab-dependent cellular cytotoxicity by natural killer cells. This increased sensitivity to cytotoxicity was partially dependent on tumor necrosis factor-related apoptosis-inducing ligand and perforin, respectively. This increased sensitivity was not observed following treatment with the senescence-inducing cyclin-dependent kinase-4/6 inhibitor, abemaciclib. In addition, treatment with DXR, but not abemaciclib, decreased the expression of antiapoptotic proteins in cancer cells. These results indicated that DXR and abemaciclib induced senescence in breast cancer cells, but that they differed in their sensitivity to immune cell-mediated cytotoxicity. These findings could provide an indication for combining anticancer immunotherapy with chemotherapeutic drugs or molecular targeting drugs.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias da Mama/tratamento farmacológico , Linfócitos T CD4-Positivos/imunologia , Senescência Celular/imunologia , Células Matadoras Naturais/imunologia , Aminopiridinas/farmacologia , Aminopiridinas/uso terapêutico , Citotoxicidade Celular Dependente de Anticorpos/efeitos dos fármacos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Apoptose/efeitos dos fármacos , Apoptose/imunologia , Proteínas Reguladoras de Apoptose/imunologia , Proteínas Reguladoras de Apoptose/metabolismo , Benzimidazóis/farmacologia , Benzimidazóis/uso terapêutico , Neoplasias da Mama/imunologia , Neoplasias da Mama/patologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linhagem Celular Tumoral , Senescência Celular/efeitos dos fármacos , Quinase 4 Dependente de Ciclina/antagonistas & inibidores , Quinase 6 Dependente de Ciclina/antagonistas & inibidores , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Células Matadoras Naturais/efeitos dos fármacos , Terapia de Alvo Molecular/métodos , Recidiva Local de Neoplasia
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