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1.
Nat Commun ; 11(1): 4520, 2020 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-32908154

RESUMO

Tumor extracellular matrix has been associated with drug resistance and immune suppression. Here, proteomic and RNA profiling reveal increased collagen levels in lung tumors resistant to PD-1/PD-L1 blockade. Additionally, elevated collagen correlates with decreased total CD8+ T cells and increased exhausted CD8+ T cell subpopulations in murine and human lung tumors. Collagen-induced T cell exhaustion occurs through the receptor LAIR1, which is upregulated following CD18 interaction with collagen, and induces T cell exhaustion through SHP-1. Reduction in tumor collagen deposition through LOXL2 suppression increases T cell infiltration, diminishes exhausted T cells, and abrogates resistance to anti-PD-L1. Abrogating LAIR1 immunosuppression through LAIR2 overexpression or SHP-1 inhibition sensitizes resistant lung tumors to anti-PD-1. Clinically, increased collagen, LAIR1, and TIM-3 expression in melanoma patients treated with PD-1 blockade predict poorer survival and response. Our study identifies collagen and LAIR1 as potential markers for immunotherapy resistance and validates multiple promising therapeutic combinations.


Assuntos
Adenocarcinoma de Pulmão/tratamento farmacológico , Antineoplásicos Imunológicos/farmacologia , Linfócitos T CD8-Positivos/imunologia , Colágeno/metabolismo , Resistencia a Medicamentos Antineoplásicos/imunologia , Neoplasias Pulmonares/tratamento farmacológico , Receptores Imunológicos/metabolismo , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/imunologia , Adenocarcinoma de Pulmão/patologia , Aminoácido Oxirredutases/genética , Aminoácido Oxirredutases/metabolismo , Animais , Antineoplásicos Imunológicos/uso terapêutico , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/imunologia , Biomarcadores Tumorais/metabolismo , Carcinoma Pulmonar de Lewis/tratamento farmacológico , Carcinoma Pulmonar de Lewis/imunologia , Carcinoma Pulmonar de Lewis/patologia , Linhagem Celular Tumoral , Conjuntos de Dados como Assunto , Modelos Animais de Doenças , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/imunologia , Matriz Extracelular/patologia , Feminino , Técnicas de Silenciamento de Genes , Células HEK293 , Receptor Celular 2 do Vírus da Hepatite A/metabolismo , Humanos , Pulmão/imunologia , Pulmão/patologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Camundongos Transgênicos , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/imunologia , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/genética , RNA-Seq , Receptores Imunológicos/genética
2.
Proc Natl Acad Sci U S A ; 117(25): 14342-14353, 2020 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-32513716

RESUMO

Immature T cells undergo a process of positive selection in the thymus when their new T cell receptor (TCR) engages and signals in response to self-peptides. As the T cell matures, a slew of negative regulatory molecules, including the inhibitory surface glycoprotein CD5, are up-regulated in proportion to the strength of the self-peptide signal. Together these regulators dampen TCR-proximal signaling and help avoid any subsequent peripheral activation of T cells by self-peptides. Paradoxically, antigen-specific T cells initially expressing more CD5 (CD5hi) have been found to better persist as effector/memory cells after a peripheral challenge. The molecular mechanisms underlying such a duality in CD5 function is not clear. We found that CD5 alters the basal activity of the NF-κB signaling in resting peripheral T cells. When CD5 was conditionally ablated, T cells were unable to maintain higher expression of the cytoplasmic NF-κB inhibitor IκBα. Consistent with this, resting CD5hi T cells expressed more of the NF-κB p65 protein than CD5lo cells, without significant increases in transcript levels, in the absence of TCR signals. This posttranslationally stabilized cellular NF-κB depot potentially confers a survival advantage to CD5hi T cells over CD5lo ones. Taken together, these data suggest a two-step model whereby the strength of self-peptide-induced TCR signal lead to the up-regulation of CD5, which subsequently maintains a proportional reserve of NF-κB in peripheral T cells poised for responding to agonistic antigen-driven T cell activation.


Assuntos
Antígenos CD5/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/imunologia , Inibidor de NF-kappaB alfa/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo , Linfócitos T/imunologia , Transferência Adotiva , Animais , Apresentação do Antígeno/imunologia , Antígenos CD5/genética , Linhagem Celular Tumoral , Separação Celular , Sobrevivência Celular/imunologia , Feminino , Citometria de Fluxo , Lipopolissacarídeos/imunologia , Ativação Linfocitária , Camundongos , Camundongos Knockout , Modelos Animais , Cultura Primária de Células , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Receptores de Antígenos de Linfócitos T alfa-beta/metabolismo , Transdução de Sinais/imunologia , Linfócitos T/metabolismo , Linfócitos T/transplante , Timo/citologia , Timo/crescimento & desenvolvimento , Timo/imunologia , Fator de Transcrição RelA/metabolismo , Regulação para Cima
3.
Adv Exp Med Biol ; 1204: 215-230, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32152949

RESUMO

Siglecs are a family of transmembrane receptor-like glycan-recognition proteins expressed primarily on leukocytes. Majority of Siglecs have an intracellular sequence motif called immunoreceptor tyrosine-based inhibitory motif (ITIM) and associate with Src homology region 2 domain-containing tyrosine phosphatase-1 (SHP-1), and negatively regulate tyrosine phosphorylation-mediated intracellular signaling events. On the other hand, some Siglecs have a positively charged amino acid residue in the transmembrane domain and associate with DNAX activation protein of 12 kDa (DAP12), which in turn recruits spleen tyrosine kinase (Syk). These DAP12-associated Siglecs play diverse functions. For example, Siglec-15 is conserved throughout vertebrate evolution and plays a role in bone homeostasis by regulating osteoclast development and function. Human Siglec-14 and -16 have inhibitory counterparts (Siglec-5 and -11, respectively), which show extremely high sequence similarity with them at the extracellular domain but interact with SHP-1. The DAP12-associated Siglec in such "paired receptor" configuration counteracts the pathogens that exploit the inhibitory counterpart. Polymorphisms (mutations) that render DAP12-associated inactive Siglecs are found in humans, and some of these appear to be associated with sensitivity or resistance of human hosts to bacterially induced conditions. Studies of mouse Siglec-H have revealed complex and intriguing functions it plays in regulating adaptive immunity. Many questions remain unanswered, and further molecular and genetic studies of DAP12-associated Siglecs will yield valuable insights with translational relevance.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas de Membrana/metabolismo , Lectinas Semelhantes a Imunoglobulina de Ligação ao Ácido Siálico/imunologia , Lectinas Semelhantes a Imunoglobulina de Ligação ao Ácido Siálico/metabolismo , Animais , Humanos , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo , Transdução de Sinais
4.
PLoS One ; 15(1): e0227449, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32004354

RESUMO

The SOD3 variant, SOD3R213G, results from substitution of arginine to glycine at amino acid 213 (R213G) in its heparin binding domain (HBD) and is a common genetic variant, reported to be associated with ischemic heart disease. However, little is understood about the role of SOD3R213G in innate immune function, and how it leads to dysfunction of the cardiovascular system. We observed pathologic changes in SOD3R213G transgenic (Tg) mice, including cystic medial degeneration of the aorta, heart inflammation, and increased circulating and organ infiltrating neutrophils. Interestingly, SOD3R213G altered the profile of SOD3 interacting proteins in neutrophils in response to G-CSF. Unexpectedly, we found that G-CSF mediated tyrosine phosphatase, SH-PTP1 was down-regulated in the neutrophils of SOD3R213G overexpressing mice. These effects were recovered by reconstitution with Wt SOD3 expressing bone marrow cells. Overall, our study reveals that SOD3R213G plays a crucial role in the function of the cardiovascular system by controlling innate immune response and signaling. These results suggest that reconstitution with SOD3 expressing bone marrow cells may be a therapeutic strategy to treat SOD3R213G mediated diseases.


Assuntos
Infiltração de Neutrófilos/fisiologia , Neutrófilos/metabolismo , Superóxido Dismutase/metabolismo , Animais , Aorta/metabolismo , Aorta/patologia , Células da Medula Óssea/citologia , Células da Medula Óssea/metabolismo , Proliferação de Células , Modelos Animais de Doenças , Regulação para Baixo , Fator Estimulador de Colônias de Granulócitos/metabolismo , Cardiopatias/imunologia , Cardiopatias/metabolismo , Cardiopatias/patologia , Imunidade Inata , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mutagênese Sítio-Dirigida , Miocárdio/metabolismo , Miocárdio/patologia , Neutrófilos/citologia , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo , Receptores CCR2/metabolismo , Transdução de Sinais , Superóxido Dismutase/genética
5.
Cancer Cell ; 37(2): 216-225.e6, 2020 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-32004441

RESUMO

Chimeric antigen receptor (CAR) T cell costimulation mediated by CD28 and 4-1BB is essential for CAR-T cell-induced tumor regression. However, CD28 and 4-1BB differentially modulate kinetics, metabolism and persistence of CAR-T cells, and the mechanisms governing these differences are not fully understood. We found that LCK recruited into the synapse of CD28-encoding CAR by co-receptors causes antigen-independent CAR-CD3ζ phosphorylation and increased antigen-dependent T cell activation. In contrast, the synapse formed by 4-1BB-encoding CAR recruits the THEMIS-SHP1 phosphatase complex that attenuates CAR-CD3ζ phosphorylation. We further demonstrated that the CAR synapse can be engineered to recruit either LCK to enhance the kinetics of tumor killing of 4-1BB CAR-T cells or SHP1 to tune down cytokine release of CD28 CAR-T cells.


Assuntos
Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo , Receptores de Antígenos Quiméricos/metabolismo , Animais , Antígenos CD28/imunologia , Linhagem Celular Tumoral , Citocinas/metabolismo , Humanos , Ativação Linfocitária/imunologia , Camundongos Transgênicos , Receptores de Antígenos de Linfócitos T/imunologia , Linfócitos T/imunologia , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/metabolismo
6.
Nature ; 577(7792): 682-688, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31942069

RESUMO

Mycobacterium tuberculosis is an intracellular pathogen that uses several strategies to interfere with the signalling functions of host immune molecules. Many other bacterial pathogens exploit the host ubiquitination system to promote pathogenesis1,2, but whether this same system modulates the ubiquitination of M. tuberculosis proteins is unknown. Here we report that the host E3 ubiquitin ligase ANAPC2-a core subunit of the anaphase-promoting complex/cyclosome-interacts with the mycobacterial protein Rv0222 and promotes the attachment of lysine-11-linked ubiquitin chains to lysine 76 of Rv0222 in order to suppress the expression of proinflammatory cytokines. Inhibition of ANAPC2 by specific short hairpin RNA abolishes the inhibitory effect of Rv0222 on proinflammatory responses. Moreover, mutation of the ubiquitination site on Rv0222 impairs the inhibition of proinflammatory cytokines by Rv0222 and reduces virulence during infection in mice. Mechanistically, lysine-11-linked ubiquitination of Rv0222 by ANAPC2 facilitates the recruitment of the protein tyrosine phosphatase SHP1 to the adaptor protein TRAF6, preventing the lysine-63-linked ubiquitination and activation of TRAF6. Our findings identify a previously unrecognized mechanism that M. tuberculosis uses to suppress host immunity, and provide insights relevant to the development of effective immunomodulators that target M. tuberculosis.


Assuntos
Proteínas de Bactérias/imunologia , Proteínas de Bactérias/metabolismo , Interações Hospedeiro-Patógeno/imunologia , Mycobacterium tuberculosis/imunologia , Tuberculose/imunologia , Ubiquitinação , Ciclossomo-Complexo Promotor de Anáfase/química , Animais , Subunidade Apc2 do Ciclossomo-Complexo Promotor de Anáfase/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Células Cultivadas , Citocinas/antagonistas & inibidores , Citocinas/imunologia , Citocinas/metabolismo , Feminino , Mediadores da Inflamação/antagonistas & inibidores , Mediadores da Inflamação/imunologia , Mediadores da Inflamação/metabolismo , Lisina/metabolismo , Macrófagos/imunologia , Macrófagos/metabolismo , Macrófagos/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo , Transdução de Sinais , Fator 6 Associado a Receptor de TNF/antagonistas & inibidores , Fator 6 Associado a Receptor de TNF/metabolismo , Fator de Transcrição AP-1/metabolismo , Tuberculose/microbiologia , Virulência/imunologia
7.
Nat Immunol ; 21(1): 54-64, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31819256

RESUMO

Ptpn6 is a cytoplasmic phosphatase that functions to prevent autoimmune and interleukin-1 (IL-1) receptor-dependent, caspase-1-independent inflammatory disease. Conditional deletion of Ptpn6 in neutrophils (Ptpn6∆PMN) is sufficient to initiate IL-1 receptor-dependent cutaneous inflammatory disease, but the source of IL-1 and the mechanisms behind IL-1 release remain unclear. Here, we investigate the mechanisms controlling IL-1α/ß release from neutrophils by inhibiting caspase-8-dependent apoptosis and Ripk1-Ripk3-Mlkl-regulated necroptosis. Loss of Ripk1 accelerated disease onset, whereas combined deletion of caspase-8 and either Ripk3 or Mlkl strongly protected Ptpn6∆PMN mice. Ptpn6∆PMN neutrophils displayed increased p38 mitogen-activated protein kinase-dependent Ripk1-independent IL-1 and tumor necrosis factor production, and were prone to cell death. Together, these data emphasize dual functions for Ptpn6 in the negative regulation of p38 mitogen-activated protein kinase activation to control tumor necrosis factor and IL-1α/ß expression, and in maintaining Ripk1 function to prevent caspase-8- and Ripk3-Mlkl-dependent cell death and concomitant IL-1α/ß release.


Assuntos
Apoptose/imunologia , Caspase 8/imunologia , Neutrófilos/imunologia , Proteínas Quinases/imunologia , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/imunologia , Animais , Caspase 8/genética , Células Cultivadas , Deleção de Genes , Inflamação/imunologia , Interleucina-1/imunologia , Interleucina-1alfa/metabolismo , Interleucina-1beta/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína Tirosina Fosfatase não Receptora Tipo 6/genética , Receptores Tipo I de Interleucina-1/imunologia , Fator de Necrose Tumoral alfa/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
8.
Zhonghua Yi Xue Za Zhi ; 99(36): 2811-2815, 2019 Sep 24.
Artigo em Chinês | MEDLINE | ID: mdl-31550807

RESUMO

Objective: To assess the methylation level of SHP-1 promoter region and the effects on the phosphorylation of the Signal Transducers and Activators of Transcription 3 (STAT3) protein in bone marrow specimen of patients with myelodysplastic syndrome (MDS), and to explore the relationship of SHP-1 methylation and prognosis of the patients. Method: Bone marrow specimens of 93 patients with MDS were collected from the General Hospital of Tianjin Medical University from September 2010 to June 2014. The enrolled subjects included 54 males and 39 females and they were divided into the low-risk group (IPSS score:0-1.0, median: 0.5) and the high-risk group (IPSS score: 1.5-3.0, median: 2.5) according to the International Prognostic Score System (IPSS). The methylation level of SHP-1 was detected by methylation-specific polymerase chain reaction, and the level of p-STAT3 was detected using Western blot. Results: In the high-risk group, 64.44% (29/45) of the patients had methylation in the SHP-1 promoter region, which was significantly higher than the low-risk group 22.92% (11/48). Therefore, SHP-1 methylation was frequently presented in the patients of the high-risk group. Similarly, 66.67% (30/45) of the patients in the high-risk group had positive STAT3 phosphorylation status, whereas only 20.83% (10/48) were tested positive in the low-risk group. In addition, correlation analysis also revealed that the SHP-1 methylation rate was positively correlated with the positive rate of STAT3 phosphorylation (r=0.57,P<0.001). Conclusions: SHP-1 methylation is significantly correlated with the risk of MDS patients. It may be used as an independent predictor of shorter survival in patients of the high-risk group. The increased level of SHP-1 methylation will lead to the uncontrolled activation of the downstream JAK/STAT3 pathway, which in turn can cause further positive feedback to amplify the carcinogenic signal.


Assuntos
Síndromes Mielodisplásicas , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo , Fator de Transcrição STAT3/metabolismo , Metilação de DNA , Feminino , Humanos , Masculino , Fosforilação , Prognóstico
9.
Elife ; 82019 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-31436532

RESUMO

The immunoreceptor tyrosine-based inhibition motif (ITIM)-containing receptor G6b-B is critical for platelet production and activation. Loss of G6b-B results in severe macrothrombocytopenia, myelofibrosis and aberrant platelet function in mice and humans. Using a combination of immunohistochemistry, affinity chromatography and proteomics, we identified the extracellular matrix heparan sulfate (HS) proteoglycan perlecan as a G6b-B binding partner. Subsequent in vitro biochemical studies and a cell-based genetic screen demonstrated that the interaction is specifically mediated by the HS chains of perlecan. Biophysical analysis revealed that heparin forms a high-affinity complex with G6b-B and mediates dimerization. Using platelets from humans and genetically modified mice, we demonstrate that binding of G6b-B to HS and multivalent heparin inhibits platelet and megakaryocyte function by inducing downstream signaling via the tyrosine phosphatases Shp1 and Shp2. Our findings provide novel insights into how G6b-B is regulated and contribute to our understanding of the interaction of megakaryocytes and platelets with glycans.


Assuntos
Plaquetas/fisiologia , Heparitina Sulfato/metabolismo , Megacariócitos/fisiologia , Receptores Imunológicos/metabolismo , Animais , Humanos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Ligação Proteica , Multimerização Proteica , Proteína Tirosina Fosfatase não Receptora Tipo 11/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo , Receptores Imunológicos/deficiência , Receptores Imunológicos/genética , Transdução de Sinais
10.
Immunobiology ; 224(5): 605-613, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31402149

RESUMO

PURPOSE: The delayed rejection caused by strong cell-mediated innate and adaptive xenogeneic immune responses continues to be a major obstacle. Therefore, suppressing macrophage function could be effective in avoiding this type of rejection. In this study, the suppression of T-cell immunoglobulin and ITIM domain (TIGIT) function against macrophage-mediated xenogeneic rejection was investigated. MATERIAL AND METHODS: Naïve porcine aortic endothelial cell (PAEC) and PAEC transfectant with TIGIT (PAEC/TIGIT) were co-cultured with M1 macrophages, and the degree of cytotoxicity was determined by a counting beads assay. The anti/pro-inflammatory gene expression was determined by RT-PCR and the phosphorylated SHP-1 in the macrophages after co-culturing with PAEC or PAEC/TIGIT was evaluated by western blotting. RESULTS: CD155 was expressed at essentially equal levels on both M1 and M2 macrophages, whereas TIGIT was highly expressed on M2 macrophages but not in M1 macrophages. TIGIT on PAEC significantly reduced the cytotoxicity of M1 macrophages but no significant suppression of phagocytosis was detected. TIGIT also caused a decrease in the expression of pro-inflammatory cytokines, namely TNFα, IL-1ß and IL-12 in M1 macrophages. Furthermore, PAEC/TIGIT caused a significant increase in phosphorylated SHP-1 in M1 macrophages compared to PAEC. CONCLUSION: The findings of this study indicate that TIGIT suppresses xenogeneic M1 macrophage-induced cytotoxicity, probably at least in part, via the phosphorylation of SHP-1. In addition, the reduced expression of some pro-inflammatory cytokines, namely TNFα, IL-1ß and IL-12, was observed in M1 macrophages that had been cultured with PAEC/TIGIT.


Assuntos
Aorta/metabolismo , Citotoxicidade Imunológica , Células Endoteliais/metabolismo , Macrófagos/imunologia , Macrófagos/metabolismo , Receptores Imunológicos/genética , Imunidade Adaptativa , Animais , Aorta/imunologia , Células Cultivadas , Citocinas/metabolismo , Citotoxicidade Imunológica/genética , Células Endoteliais/imunologia , Expressão Gênica , Rejeição de Enxerto/genética , Rejeição de Enxerto/imunologia , Xenoenxertos , Humanos , Imunidade Inata , Mediadores da Inflamação/metabolismo , Modelos Biológicos , Fagocitose/genética , Fagocitose/imunologia , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo , Receptores Imunológicos/metabolismo , Receptores Virais/genética , Receptores Virais/metabolismo , Transdução de Sinais , Suínos , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo
11.
Int Immunopharmacol ; 74: 105702, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31228819

RESUMO

Sauchinone, the biologically active lignan of Saururus chinensis, has been reported to have anti-inflammatory, antitumor, antioxidant, and hepatoprotective properties. However, little is known about the effect of sauchinone on FcεRI-mediated mast cell activation. The aim of this study was to evaluate the anti-allergic activity of sauchinone and the underlying mechanism using mouse bone marrow-derived mast cells (BMMCs) and the mast cell-mediated passive cutaneous anaphylaxis (PCA) model. Sauchinone markedly suppressed FcεRI-mediated activation of positive signaling mediators, including Syk, linker for activation of T cells (LAT), phospholipase C (PLC)γ, mitogen-activated protein (MAP) kinases, Akt, IκB kinase (IKK), and intracellular Ca2+, and increased the activation of negative signaling mediators, including liver kinase B (LKB)1/AMP-activated protein kinase (AMPK) and Src homology 2 domain-containing protein tyrosine phosphatase (SHP)-1. Interestingly, sauchinone increased the interaction between SHP-1 and Syk. Consequently, sauchinone significantly suppressed FcεRI-mediated BMMC degranulation and synthesis of eicosanoids and cytokines. These inhibitory effects of sauchinone were diminished in BMMCs treated with siRNAs targeting LKB1, AMPKα2, or SHP-1, and in BMMCs isolated from AMPKα2-deficient mice. In addition, administration of sauchinone markedly suppressed the IgE-mediated PCA reaction in wild-type mice, and this inhibitory effect was significantly reduced in AMPKα2-/- mice. Taken together, these data suggest that sauchinone suppresses FcεRI-mediated mast cell activation and anaphylaxis through modulation of the LKB1/AMPK and SHP-1/Syk pathways. Therefore, sauchinone might be a potential therapeutic agent for the treatment of allergic inflammatory diseases.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Anafilaxia/tratamento farmacológico , Hipersensibilidade/tratamento farmacológico , Mastócitos/fisiologia , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Quinase Syk/metabolismo , Proteínas Quinases Ativadas por AMP/genética , Animais , Células Cultivadas , Modelos Animais de Doenças , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores de IgG/metabolismo , Transdução de Sinais
12.
Immunity ; 51(2): 310-323.e7, 2019 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-31204070

RESUMO

The tumor necrosis factor receptor superfamily member HVEM is one of the most frequently mutated surface proteins in germinal center (GC)-derived B cell lymphomas. We found that HVEM deficiency increased B cell competitiveness during pre-GC and GC responses. The immunoglobulin (Ig) superfamily protein BTLA regulated HVEM-expressing B cell responses independently of B-cell-intrinsic signaling via HVEM or BTLA. BTLA signaling into T cells through the phosphatase SHP1 reduced T cell receptor (TCR) signaling and preformed CD40 ligand mobilization to the immunological synapse, thus diminishing the help delivered to B cells. Moreover, T cell deficiency in BTLA cooperated with B cell Bcl-2 overexpression, leading to GC B cell outgrowth. These results establish that HVEM restrains the T helper signals delivered to B cells to influence GC selection outcomes, and they suggest that BTLA functions as a cell-extrinsic suppressor of GC B cell lymphomagenesis.


Assuntos
Linfócitos B/imunologia , Centro Germinativo/imunologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Receptores Imunológicos/metabolismo , Membro 14 de Receptores do Fator de Necrose Tumoral/metabolismo , Linfócitos T Auxiliares-Indutores/imunologia , Animais , Proliferação de Células , Sinapses Imunológicas , Ativação Linfocitária , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Comunicação Parácrina , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Receptores de Antígenos de Linfócitos T/metabolismo , Receptores Imunológicos/genética , Transdução de Sinais
13.
Emerg Microbes Infect ; 8(1): 734-748, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31130074

RESUMO

Many pathogens infect hosts through various immune evasion strategies. However, the molecular mechanisms by which pathogen proteins modulate and evade the host immune response remain unclear. Enterohemorrhagic Escherichia coli (EHEC) is a pathological strain that can induce mitogen-activated protein (MAP) kinase (Erk, Jnk and p38 MAPK) and NF-κB pathway activation and proinflammatory cytokine production, which then causes diarrheal diseases such as hemorrhagic colitis and hemolytic uremic syndrome. Transforming growth factor ß-activated kinase-1 (TAK1) is a key regulator involved in distinct innate immune signalling pathways. Here we report that EHEC translocated intimin receptor (Tir) protein inhibits the expression of EHEC-induced proinflammatory cytokines by interacting with the host tyrosine phosphatase SHP-1, which is dependent on the phosphorylation of immunoreceptor tyrosine-based inhibition motifs (ITIMs). Mechanistically, the association of EHEC Tir with SHP-1 facilitated the recruitment of SHP-1 to TAK1 and inhibited TAK1 phosphorylation, which then negatively regulated K63-linked polyubiquitination of TAK1 and downstream signal transduction. Taken together, these results suggest that EHEC Tir negatively regulates proinflammatory responses by inhibiting the activation of TAK1, which is essential for immune evasion and could be a potential target for the treatment of bacterial infection.


Assuntos
Escherichia coli Êntero-Hemorrágica/patogenicidade , Infecções por Escherichia coli/fisiopatologia , Proteínas de Escherichia coli/metabolismo , Interações Hospedeiro-Patógeno , Evasão da Resposta Imune , MAP Quinase Quinase Quinases/antagonistas & inibidores , Receptores de Superfície Celular/metabolismo , Fatores de Virulência/metabolismo , Animais , Infecções por Escherichia coli/microbiologia , Células HEK293 , Humanos , Macrófagos Peritoneais , Camundongos , Camundongos Endogâmicos C57BL , Ligação Proteica , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo , Células RAW 264.7
14.
Med Sci Monit ; 25: 3238-3246, 2019 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-31044775

RESUMO

BACKGROUND The TMEFF2 gene encodes the transmembrane protein with EGF like and two follistatin-like domains 2 and has been reported to be a tumor suppressor gene, but its role remains unknown in pancreatic cancer. This study aimed to investigate the expression of TMEFF2 in human pancreatic cancer tissue and the effects of knockdown of TMEFF2 on cell, proliferation, and apoptosis in human pancreatic cell lines. MATERIAL AND METHODS Thirty-five samples of human pancreatic tissue and adjacent normal pancreatic tissue, and five human pancreatic cancer cell lines, CAPAN1, ASPC1, BXPC3, SW1990, and CFPAC were studied. RNA expression, protein expression, cell proliferation, and apoptosis were studied using real-time polymerase chain reaction (RT-PCR), Western blot, the cell counting kit-8 (CCK-8) assay, and flow cytometry, respectively. A co-immunoprecipitation assay evaluated protein interactions. RESULTS TMEFF2 expression was down-regulated in pancreatic cancer tissue compared with normal pancreas. In human pancreatic cancer cell lines, overexpression of TMEFF2 suppressed cell proliferation and enhanced apoptosis, suppressed the expression of p-STAT3, MCL1, VEGF and increased the expression of the tyrosine-specific protein phosphatase, SHP-1. The co-immunoprecipitation assay showed that TMEFF2 interacted with SHP-1. Knockdown of expression of TMEFF2 resulted in the increased expression of p-STAT3, MCL1, and VEGF, increased cell proliferation and decreased cell apoptosis, which were reversed by overexpression of SHP-1. CONCLUSIONS In pancreatic cancer, TMEFF2 exerted as a tumor suppressor effect by regulating p-STAT3, MCL1, and VEGF via SHP-1.


Assuntos
Proteínas de Membrana/biossíntese , Proteínas de Neoplasias/biossíntese , Neoplasias Pancreáticas/metabolismo , Antineoplásicos Fitogênicos/farmacologia , Apoptose/fisiologia , Pontos de Checagem do Ciclo Celular/fisiologia , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Regulação para Baixo , Técnicas de Silenciamento de Genes , Células HEK293 , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Mitocôndrias/metabolismo , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Metástase Neoplásica , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo , Fator de Transcrição STAT3/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
15.
Physiol Rep ; 7(8): e14066, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-31033226

RESUMO

Sickle cell disease (SCD)-induced urinary concentration defect has been proposed as caused by impaired ability of the occluded vasa recta due to red blood cell sickling to serve as countercurrent exchangers and renal tubules to absorb water and solutes. However, the exact molecular mechanisms remain largely unknown. The present studies were undertaken to determine the effects of SCD on vasopressin, aquaporin2 (AQP2), urea transporter A1 (UTA1), Na-K-Cl co-transporter 2 (NKCC2), epithelial Na channels (ENaC), aquaporin1 (AQP1), nuclear factor of activated T cells 5 (NFAT5) and Src homology region-2 domain-containing phosphatase-1 (SHP-1), an important regulator of NFAT5, in the Berkeley SCD mouse kidney medulla. Under water repletion, SCD only induced a minor urinary concentration defect associated with increased urinary vasopressin level alone with the well-known effects of vasopressin: protein abundance of AQP2, UTA1 and ENaC-ß and apical targeting of AQP2 as compared with non-SCD. SCD did not significantly affect AQP1 protein level. Water restriction had no further significant effect on SCD urinary vasopressin. NFAT5 is also critical to urinary concentration. Instead, water restriction-activated NFAT5 associated with inhibition of SHP-1 in the SCD mice. Yet, water restriction only elevated urinary osmolality by 28% in these mice as opposed to 104% in non-SCD mice despite similar degree increases of protein abundance of AQP2, NKCC2 and AQP2-S256-P. Water-restriction had no significant effect on protein abundance of ENaC or AQP1 in either strain. In conclusion, under water repletion SCD, only induces a minor defect in urinary concentration because of compensation from the up-regulated vasopressin system. However, under water restriction, SCD mice struggle to concentrate urine despite activating NFAT5. SCD-induced urinary concentration defect appears to be resulted from the poor blood flow in vasa recta rather than the renal tubules' ability to absorb water and solutes.


Assuntos
Anemia Falciforme/metabolismo , Aquaporina 2/metabolismo , Canais Epiteliais de Sódio/metabolismo , Rim/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Membro 1 da Família 12 de Carreador de Soluto/metabolismo , Vasopressinas/metabolismo , Anemia Falciforme/urina , Animais , Aquaporina 1/metabolismo , Aquaporina 2/genética , Canais Epiteliais de Sódio/genética , Feminino , Masculino , Proteínas de Membrana Transportadoras/genética , Camundongos , Proteína Tirosina Fosfatase não Receptora Tipo 6/genética , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo , Membro 1 da Família 12 de Carreador de Soluto/genética , Fatores de Transcrição/metabolismo , Regulação para Cima , Equilíbrio Hidroeletrolítico
16.
Biochem Biophys Res Commun ; 513(2): 360-367, 2019 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-30961932

RESUMO

Apoptosis of tubular epithelium cells (TECs) plays critical roles in renal ischemia reperfusion (I/R) injury, but the molecular regulatory mechanisms of apoptosis still require further investigation. Recently, phosphatase family members have been suggested to regulate multiple aspects of the injury and regeneration response. However, the roles of SHP-1, an important protein-tyrosine phosphatase, in the regulation of renal I/R injury remain unknown. Here, we found that SHP-1 knockdown in vivo significantly increased renal I/R injury and aggravated the apoptosis of TECs. Consistently, after SHP-1 knockdown in TECs in vitro, a sharp increase of apoptosis induced by cobalt dichloride was found. The protective role of SHP-1 was also validated in a TEC cell line stably overexpressing SHP-1. Mechanistically, the ASK1/MKK4/JNK pro-apoptosis signal was over activated after SHP-1 knockdown, and SHP-1 could bind to and dephosphorylate ASK1 to inhibit its activation, thus repressing apoptosis.


Assuntos
MAP Quinase Quinase Quinase 5/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo , Insuficiência Renal/metabolismo , Traumatismo por Reperfusão/metabolismo , Animais , Apoptose , Células HEK293 , Humanos , Rim/metabolismo , Rim/patologia , Camundongos Endogâmicos C57BL , Fosforilação , Insuficiência Renal/patologia , Traumatismo por Reperfusão/patologia , Transdução de Sinais
17.
Eur J Pharmacol ; 854: 62-69, 2019 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-30951721

RESUMO

Src Homology 2 domain-containing protein tyrosine phosphatase 1 (SHP1) interacts specifically with GluN2A subunit of N-methyl-D-aspartate (NMDA) subtype of glutamate receptors in spinal cord dorsal horn. This molecular interaction is involved in the development of GluN2A-dependent spinal sensitization of nociceptive behaviors. Intrathecal application of a GluN2A-derived polypeptide (short for pep-GluN2A) has been shown to disturb spinal GluN2A/SHP1 interaction and inhibit inflammatory pain. Here we found that SHP1 was also located at dorsal root ganglion (DRG) neurons and formed complexes with GluN2A subunit. Peripheral inflammation activated SHP1 in DRG neurons, which promoted GluN2A tyrosine phosphorylation. The SHP1 binding to GluN2A facilitated the glutamate release from primary afferent fibers and exaggerated nociceptive synaptic transmission onto postsynaptic spinal cord neurons. Our data showed that intradermal application of pep-GluN2A disrupted GluN2A/SHP1 interaction in DRG neurons, attenuated the ability of GluN2A subunit-containing NMDA receptors to regulate the presynaptic glutamate release and more importantly, alleviated the pain hypersensitivity caused by carrageenan, complete Freund's adjuvant and formalin. The neuropathic pain induced by spared nerve injury was also ameliorated by intradermal pep-GluN2A application. These data suggested that disruption of GluN2A/SHP1 interaction in DRG neurons generated an effective analgesic action against pathological pain.


Assuntos
Gânglios Espinais/efeitos dos fármacos , Neuralgia/tratamento farmacológico , Peptídeos/farmacologia , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Sequência de Aminoácidos , Animais , Comportamento Animal/efeitos dos fármacos , Gânglios Espinais/patologia , Masculino , Neuralgia/metabolismo , Neuralgia/patologia , Neuralgia/fisiopatologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Nociceptividade/efeitos dos fármacos , Peptídeos/química , Peptídeos/uso terapêutico , Ligação Proteica/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
18.
Nat Immunol ; 20(4): 447-457, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30833791

RESUMO

Invariant natural killer T cells (iNKT cells) develop through an incompletely understood process that requires positive selection by CD4+CD8+ double-positive thymocytes and SLAM family receptors (SFRs). Here we found that SFRs promoted the development of iNKT cells by reducing the strength of the T cell antigen receptor (TCR) signal after positive selection. This effect improved the survival of iNKT cells and their responses to antigen. Loss of SFRs upregulated the expression of inhibitory receptors, including PD-1, on iNKT cells to mitigate the deleterious effect of SFR deficiency. The role of SFRs could be mimicked by expression of SLAMF6 alone in SFR-deficient mice, and this involved the adaptor SAP-kinase Fyn complex and the phosphatase SHP-1. Thus, SFRs foster iNKT cell development by attenuating TCR signal strength after positive selection.


Assuntos
Células T Matadoras Naturais/imunologia , Receptores de Antígenos de Linfócitos T/metabolismo , Família de Moléculas de Sinalização da Ativação Linfocitária/fisiologia , Animais , Proliferação de Células , Sobrevivência Celular , Receptores Coestimuladores e Inibidores de Linfócitos T/metabolismo , Humanos , Camundongos , Camundongos Knockout , Células T Matadoras Naturais/enzimologia , Proteína Tirosina Fosfatase não Receptora Tipo 6/genética , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Proto-Oncogênicas c-fyn/metabolismo , Receptores de Antígenos de Linfócitos T/imunologia , Transdução de Sinais , Proteína Associada à Molécula de Sinalização da Ativação Linfocitária/genética , Família de Moléculas de Sinalização da Ativação Linfocitária/genética , Família de Moléculas de Sinalização da Ativação Linfocitária/metabolismo
19.
Leukemia ; 33(10): 2416-2428, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-30872780

RESUMO

The BCL-2 inhibitor venetoclax has only limited activity in DLBCL despite frequent BCL-2 overexpression. Since constitutive activation of the B cell receptor (BCR) pathway has been reported in both ABC and GCB DLBCL, we investigated whether targeting SYK or BTK will increase sensitivity of DLBCL cells to venetoclax. We report that pharmacological inhibition of SYK or BTK synergistically enhances venetoclax sensitivity in BCL-2-positive DLBCL cell lines with an activated BCR pathway in vitro and in a xenograft model in vivo, despite the only modest direct cytotoxic effect. We further show that these sensitizing effects are associated with inhibition of the downstream PI3K/AKT pathway and changes in the expression of MCL-1, BIM, and HRK. In addition, we show that BCR-dependent GCB DLBCL cells are characterized by deficiency of the phosphatase SHP1, a key negative regulator of the BCR pathway. Re-expression of SHP1 in GCB DBLCL cells reduces SYK, BLNK, and GSK3 phosphorylation and induces corresponding changes in MCL1, BIM, and HRK expression. Together, these findings suggest that SHP1 deficiency is responsible for the constitutive activation of the BCR pathway in GCB DLBCL and identify SHP1 and BCL-2 as potential predictive markers for response to treatment with a venetoclax/BCR inhibitor combination.


Assuntos
Tirosina Quinase da Agamaglobulinemia/metabolismo , Antineoplásicos/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Sulfonamidas/farmacologia , Quinase Syk/metabolismo , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Linfoma Difuso de Grandes Células B/metabolismo , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
20.
Mol Med Rep ; 19(4): 3273-3282, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30816454

RESUMO

The human protein tyrosine phosphatase, non­receptor type 6 (PTPN6) gene is located on chromosome 12p13 and encodes an Mr 68,000 non­receptor type protein­tyrosine phosphatase. The PTPN6 gene has been considered as a candidate tumor suppressor in hematological and solid malignancies, and promoter methylation may be an epigenetic modification silencing its expression. However, the detailed role of PTPN6 and its promoter methylation status in the pathogenesis of esophageal squamous cell carcinoma (ESCC) has not been fully elucidated. The aim of the present study was to investigate PTPN6 expression in ESCC tissues and esophageal cancer cell lines, detect the effect of CpG hypermethylation on the activity of PTPN6, and additionally elucidate the role and prognostic significance of PTPN6 in ESCC tumorigenesis and progression. The expression of PTPN6 was identified to be significantly downregulated in esophageal cancer cell lines and ESCC tissues. Marked upregulation of PTPN6 was detected in 5­aza­2'­deoxycytidine­treated esophageal cancer cells, and frequent hypermethylation of the CpG sites within the P2 promoter (P2) was detected in ESCC tissues and esophageal cancer cell lines. The expression and methylation status of PTPN6 was associated with tumor node metastasis stage, pathological differentiation and lymph node metastasis in patients with ESCC. Aberrant hypermethylation of the P2 exhibited marked tumor specificity and was identified to be associated with the expression level of PTPN6. Downregulation and hypermethylation of PTPN6 were identified to be associated with poor ESCC patient survival. Furthermore, upregulation of PTPN6 inhibited the proliferation and invasion of esophageal cancer cells in vitro. The results of the present study suggest that PTPN6 may serve as a tumor suppressor in ESCC, and it may serve as a potential target for antitumor therapy.


Assuntos
Metilação de DNA , Carcinoma de Células Escamosas do Esôfago/genética , Carcinoma de Células Escamosas do Esôfago/patologia , Regulação Neoplásica da Expressão Gênica , Regiões Promotoras Genéticas , Proteína Tirosina Fosfatase não Receptora Tipo 6/genética , Adulto , Idoso , Azacitidina/farmacologia , Biomarcadores Tumorais , Linhagem Celular Tumoral , Ilhas de CpG , Progressão da Doença , Epigênese Genética , Carcinoma de Células Escamosas do Esôfago/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Estudos de Associação Genética , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Metástase Neoplásica , Estadiamento de Neoplasias , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo
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