RESUMO
The polarization of leukocytes toward chemoattractants is essential for the directed migration (chemotaxis) of leukocytes. How leukocytes acquire polarity after encountering chemical gradients is not well understood. We found here that leukocyte polarity was generated by TIPE2 (TNFAIP8L2), a transfer protein for phosphoinositide second messengers. TIPE2 functioned as a local enhancer of phosphoinositide-dependent signaling and cytoskeleton remodeling, which promoted leading-edge formation. Conversely, TIPE2 acted as an inhibitor of the GTPase Rac, which promoted trailing-edge polarization. Consequently, TIPE2-deficient leukocytes were defective in polarization and chemotaxis, and TIPE2-deficient mice were resistant to leukocyte-mediated neural inflammation. Thus, the leukocyte polarizer is a dual-role phosphoinositide-transfer protein and represents a potential therapeutic target for the treatment of inflammatory diseases.
Assuntos
Quimiotaxia de Leucócito/genética , Encefalomielite Autoimune Experimental/imunologia , Peptídeos e Proteínas de Sinalização Intracelular/genética , Linfócitos T/imunologia , Animais , Polaridade Celular/genética , Quimiotaxia de Leucócito/fisiologia , Inflamação/genética , Inflamação/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fosfatidilinositóis/metabolismo , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Proteínas rac de Ligação ao GTP/antagonistas & inibidoresRESUMO
OBJECTIVES: To explore the value of the synthetic MRI (SyMRI), combined with amide proton transfer-weighted (APTw) MRI for quantitative and morphologic assessment of sinonasal lesions, which could provide relative scale for the quantitative assessment of tissue properties. METHODS: A total of 80 patients (31 malignant and 49 benign) with sinonasal lesions, who underwent the SyMRI and APTw examination, were retrospectively analyzed. Quantitative parameters (T1, T2, proton density (PD)) and APT % were obtained through outlining the region of interest (ROI) and comparing the two groups utilizing independent Student t test or a Wilcoxon test. Receiver operating characteristic curve (ROC), Delong test, and logistic regression analysis were performed to assess the diagnostic efficiency of one-parameter and multiparametric models. RESULTS: SyMRI-derived mean T1, T2, and PD were significantly higher and APT % was relatively lower in benign compared to malignant sinonasal lesions (p < 0.05). The ROC analysis showed that the AUCs of the SyMRI-derived quantitative (T1, T2, PD) values and APT % ranged from 0.677 to 0.781 for differential diagnosis between benign and malignant sinonasal lesions. The T2 values showed the best diagnostic performance among all single parameters for differentiating these two masses. The AUCs of combined SyMRI-derived multiple parameters with APT % (AUC = 0.866) were the highest than that of any single parameter, which was significantly improved (p < 0.05). CONCLUSION: The combination of SyMRI and APTw imaging has the potential to reflect intrinsic tissue characteristics useful for differentiating benign from malignant sinonasal lesions. CLINICAL RELEVANCE STATEMENT: Combining synthetic MRI with amide proton transfer-weighted imaging could function as a quantitative and contrast-free approach, significantly enhancing the differentiation of benign and malignant sinonasal lesions and overcoming the limitations associated with the superficial nature of endoscopic nasal sampling. KEY POINTS: ⢠Synthetic MRI and amide proton transfer-weighted MRI could differentiate benign from malignant sinonasal lesions based on quantitative parameters. ⢠The diagnostic efficiency could be significantly improved through synthetic MRI + amide proton transfer-weighted imaging. ⢠The combination of synthetic MRI and amide proton transfer-weighted MRI is a noninvasive method to evaluate sinonasal lesions.
RESUMO
Tumour cells evade immune surveillance by upregulating the surface expression of programmed death-ligand 1 (PD-L1), which interacts with programmed death-1 (PD-1) receptor on T cells to elicit the immune checkpoint response1,2. Anti-PD-1 antibodies have shown remarkable promise in treating tumours, including metastatic melanoma2-4. However, the patient response rate is low4,5. A better understanding of PD-L1-mediated immune evasion is needed to predict patient response and improve treatment efficacy. Here we report that metastatic melanomas release extracellular vesicles, mostly in the form of exosomes, that carry PD-L1 on their surface. Stimulation with interferon-γ (IFN-γ) increases the amount of PD-L1 on these vesicles, which suppresses the function of CD8 T cells and facilitates tumour growth. In patients with metastatic melanoma, the level of circulating exosomal PD-L1 positively correlates with that of IFN-γ, and varies during the course of anti-PD-1 therapy. The magnitudes of the increase in circulating exosomal PD-L1 during early stages of treatment, as an indicator of the adaptive response of the tumour cells to T cell reinvigoration, stratifies clinical responders from non-responders. Our study unveils a mechanism by which tumour cells systemically suppress the immune system, and provides a rationale for the application of exosomal PD-L1 as a predictor for anti-PD-1 therapy.
Assuntos
Antígeno B7-H1/imunologia , Exossomos/metabolismo , Tolerância Imunológica/imunologia , Melanoma/imunologia , Receptor de Morte Celular Programada 1/imunologia , Evasão Tumoral/imunologia , Animais , Anticorpos Monoclonais Humanizados/farmacologia , Anticorpos Monoclonais Humanizados/uso terapêutico , Antineoplásicos Imunológicos/farmacologia , Antineoplásicos Imunológicos/uso terapêutico , Antígeno B7-H1/sangue , Antígeno B7-H1/metabolismo , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Estudos de Casos e Controles , Linhagem Celular Tumoral , Progressão da Doença , Feminino , Humanos , Tolerância Imunológica/efeitos dos fármacos , Interferon gama/sangue , Interferon gama/imunologia , Melanoma/tratamento farmacológico , Melanoma/patologia , Camundongos , Camundongos Nus , Metástase Neoplásica , Prognóstico , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Evasão Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Responsive feeding serves as an important protective factor for infant growth and overall health development. This study based on self-determination theory (SDT) aimed to assess the effects of a responsive breastfeeding (RBF) intervention programme on maternal breastfeeding and infant growth and development. A total of 110 mother-infant pairs were recruited and randomly divided into an intervention group (n = 55) and a control group (n = 55). The primary outcomes were breastfeeding motivation score, breastfeeding self-efficacy (BSE) and exclusive breastfeeding rate; the secondary outcomes were infant physical development at 6 weeks and 3 months. A repeated measures ANOVA indicated that the intervention group had significantly higher Enjoyment scores compared to the control group at three time points: at discharge (MD: 5.28; 95% CI: 3.68 to 6.89; p < 0.001), 6 weeks post-partum (MD: 5.06; 95% CI: 3.80 to 6.31; p < 0.001) and 3 months post-partum (MD: 5.24; 95% CI: 4.12 to 6.35; p < 0.001). Similarly, the intervention group reported significantly higher connection and mother's self-perception scores at discharge (MD: 4.31; 95% CI: 3.07 to 5.56; p < 0.001), 6 weeks post-partum (MD: 4.69; 95% CI: 3.71 to 5.68; p < 0.001) and 3 months post-partum (MD: 4.93; 95% CI: 4.14 to 5.72; p < 0.001), compared to the control group. In contrast, the pressure from significant others scores were higher in the control group relative to the intervention group at discharge (MD: -2.09; 95% CI: -2.88 to -1.31; p < 0.001), 6 weeks post-partum (MD: -4.35; 95% CI: -5.20 to -3.49; p < 0.001) and 3 months (MD: -4.89; 95% CI: -5.70 to -4.08; p < 0.001). Finally, the intervention group also reported higher Instrumental Needs scores at all three time points: at discharge (MD: 1.96; 95% CI: 1.35 to 2.58; p < 0.001), 6 weeks post-partum (MD: 3.58; 95% CI: 3.05 to 4.11; p < 0.001) and 3 months post-partum (MD: 1.18; 95% CI: 0.68 to 1.69; p < 0.001). BSE scores were significantly higher in the intervention group compared to the control group at discharge (MD: 14.29; 95% CI: 10.38 to 18.21; p < 0.001), 6 weeks post-partum (MD: 14.04; 95% CI: 11.05 to 17.02; p < 0.001) and 3 months post-partum (MD: 6.80; 95% CI: 4.66 to 8.94; p < 0.001). The rates of exclusive breastfeeding were higher in the intervention group than in the control group at each stage of the intervention (p < 0.01). At 6 weeks post-partum, the intervention group's infants showed slower weight (t = -0.90, p = 0.371) and length (t = -0.69, p = 0.495) growth compared to the control group, though not significantly. By 3 months post-partum, there was a significant difference in both weight (t = -3.46, p = 0.001) and length (t = -2.95, p = 0.004) between the groups. The findings in this study suggest that the RBF intervention programme based on SDT may be effective in improving mothers' motivation to breastfeed, building breastfeeding self-confidence and increasing the rate of exclusive breastfeeding. The effects of the intervention on infant physical development will need to be verified with longer follow-up in future research.
Assuntos
Aleitamento Materno , Autoeficácia , Humanos , Aleitamento Materno/estatística & dados numéricos , Aleitamento Materno/psicologia , Feminino , China , Adulto , Lactente , Desenvolvimento Infantil/fisiologia , Motivação , Mães/psicologia , Recém-Nascido , Adulto Jovem , Masculino , Promoção da Saúde/métodosRESUMO
Immune homeostasis is essential for the normal functioning of the immune system, and its breakdown leads to fatal inflammatory diseases. We report here the identification of a member of the tumor necrosis factor-alpha-induced protein-8 (TNFAIP8) family, designated TIPE2, that is required for maintaining immune homeostasis. TIPE2 is preferentially expressed in lymphoid tissues, and its deletion in mice leads to multiorgan inflammation, splenomegaly, and premature death. TIPE2-deficient animals are hypersensitive to septic shock, and TIPE2-deficient cells are hyper-responsive to Toll-like receptor (TLR) and T cell receptor (TCR) activation. Importantly, TIPE2 binds to caspase-8 and inhibits activating protein-1 and nuclear factor-kappaB activation while promoting Fas-induced apoptosis. Inhibiting caspase-8 significantly blocks the hyper-responsiveness of TIPE2-deficient cells. These results establish that TIPE2 is an essential negative regulator of TLR and TCR function, and its selective expression in the immune system prevents hyperresponsiveness and maintains immune homeostasis.
Assuntos
Homeostase , Imunidade , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Animais , Apoptose , Caspase 8/metabolismo , Linhagem Celular , Encefalomielite Autoimune Experimental , Humanos , Imunidade Celular , Inflamação/imunologia , Peptídeos e Proteínas de Sinalização Intracelular/química , Peptídeos e Proteínas de Sinalização Intracelular/genética , Tecido Linfoide/imunologia , Macrófagos/imunologia , Camundongos , Dados de Sequência Molecular , NF-kappa B/metabolismo , Receptores de Antígenos de Linfócitos T/imunologia , Choque Séptico/imunologia , Transdução de Sinais , Medula Espinal/imunologia , Linfócitos T/imunologia , Fator de Transcrição AP-1/metabolismo , Receptor fas/metabolismoRESUMO
The connection between cancer and inflammation is widely recognized, yet the underlying molecular mechanisms are poorly understood. We report here that TIPE2 provides a molecular bridge from inflammation to cancer by targeting the Ras signaling pathway. TIPE2 binds the Ras-interacting domain of the RalGDS family of proteins, which are essential effectors of activated Ras. This binding prevented Ras from forming an active complex, thereby inhibiting the activation of the downstream signaling molecules Ral and AKT. Consequently, TIPE2 deficiency led to heightened activation of Ral and AKT, resistance to cell death, increased migration, and dysregulation of exocyst complex formation. Conversely, TIPE2 overexpression induced cell death and significantly inhibited Ras-induced tumorigenesis in mice. Importantly, TIPE2 expression was either completely lost or significantly downregulated in human hepatic cancer. Thus, TIPE2 is an inhibitor of both inflammation and cancer, and a potential drug target for inflammatory and neoplastic diseases.
Assuntos
Genes ras , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Apoptose/genética , Sítios de Ligação , Ligação Competitiva , Carcinoma Hepatocelular/genética , Movimento Celular/genética , Transformação Celular Neoplásica/genética , Células HEK293 , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias Hepáticas/genética , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Células NIH 3T3 , Proteína Oncogênica v-akt/genética , Proteínas ral de Ligação ao GTP/genética , Fator ral de Troca do Nucleotídeo Guanina/metabolismoRESUMO
The TNF-α-induced protein 8 (TNFAIP8 or TIPE) is a risk factor for cancer and bacterial infection, and its expression is upregulated in a number of human cancers. However, its physiologic and pathologic functions are unclear. In this study, we describe the generation of TIPE-deficient mice and their increased sensitivity to colonic inflammation. TIPE-deficient mice were generated by germ line gene targeting and were born without noticeable developmental abnormalities. Their major organs, including lymphoid organs and intestines, were macroscopically and microscopically normal. However, after drinking dextran sodium sulfate-containing water, TIPE-deficient mice developed more severe colitis than wild type mice did, as demonstrated by decreased survival rates, increased body weight loss, and enhanced leukocyte infiltration, bacterial invasion, and inflammatory cytokine production in the colon. Bone marrow chimeric experiments revealed that TIPE deficiency in nonhematopoietic cells was responsible for the exacerbated colitis in TIPE-deficient mice. Consistent with this result, TIPE-deficient intestinal epithelial cells had increased rate of cell death and decreased rate of proliferation as compared with wild type controls. These findings indicate that TIPE plays an important role in maintaining colon homeostasis and in protecting against colitis.
Assuntos
Proteínas Reguladoras de Apoptose/deficiência , Colite/genética , Colite/patologia , Animais , Proteínas Reguladoras de Apoptose/genética , Linhagem Celular , Proliferação de Células , Sobrevivência Celular/genética , Colite/induzido quimicamente , Colite/metabolismo , Citocinas/sangue , Citocinas/metabolismo , Sulfato de Dextrana/efeitos adversos , Modelos Animais de Doenças , Progressão da Doença , Células Epiteliais/metabolismo , Feminino , Ordem dos Genes , Marcação de Genes , Vetores Genéticos/genética , Humanos , Mediadores da Inflamação/sangue , Mediadores da Inflamação/metabolismo , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Mucosa Intestinal/patologia , Leucócitos/patologia , Masculino , Camundongos , Camundongos Knockout , FenótipoRESUMO
TNF-α-induced protein 8 (TNFAIP8 or TIPE) is a newly described regulator of cancer and infection. However, its precise roles and mechanisms of actions are not well understood. We report in this article that TNFAIP8 regulates Listeria monocytogenes infection by controlling pathogen invasion and host cell apoptosis in a RAC1 GTPase-dependent manner. TNFAIP8-knockout mice were resistant to lethal L. monocytogenes infection and had reduced bacterial load in the liver and spleen. TNFAIP8 knockdown in murine liver HEPA1-6 cells increased apoptosis, reduced bacterial invasion into cells, and resulted in dysregulated RAC1 activation. TNFAIP8 could translocate to plasma membrane and preferentially associate with activated RAC1-GTP. The combined effect of reduced bacterial invasion and increased sensitivity to TNF-α-induced clearance likely protected the TNFAIP8-knockout mice from lethal listeriosis. Thus, by controlling bacterial invasion and the death of infected cells through RAC1, TNFAIP8 regulates the pathogenesis of L. monocytogenes infection.
Assuntos
Proteínas Reguladoras de Apoptose/genética , Apoptose/genética , Listeria monocytogenes/imunologia , Listeriose/genética , Listeriose/imunologia , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Resistência à Doença/genética , Resistência à Doença/imunologia , Guanosina Trifosfato/metabolismo , Listeriose/metabolismo , Listeriose/mortalidade , Camundongos , Camundongos Knockout , Modelos Biológicos , Ligação Proteica , Fator de Necrose Tumoral alfa/metabolismo , Proteínas rac1 de Ligação ao GTP/metabolismoRESUMO
The purpose of this study is to assess the safety and efficacy of GreenLight laser photoselective vaporization of the prostate (PVP) for the treatment of benign prostate hyperplasia/lower urinary tract symptoms (BPH/LUTS) in patients with different post-void residual urine (PVR). BPH/LUTS patients treated with PVP from January 2014 to January 2016 were enrolled in the present study. All patients were divided into PVR > 50, 50 ≤ PVR < 400, and PVR ≥ 400 ml groups, and standard general and urological methods for BPH/LUTS were carried out. PVP surgery was performed, and the follow-up outcome was investigated 6 months after surgery. A total of 429 patients were included, and there were no significant differences in comorbid diseases or habits among the three groups. The maximum urinary flow rate (Qmax) differed significantly among the groups (P < 0.001), while patients in the PVR < 50 ml group had higher maximum detrusor pressure (Pdet.max) level than the other two groups (P < 0.001). Patients in 50 ≤ PVR < 400 (P < 0.001) and PVR ≥ 400 (P < 0.001) ml groups were more likely to develop detrusor underactivity than those in the PVR < 50 ml group. All patients were treated with PVP, and there were no severe complications requiring rehospitalization or reoperation except nine designed re-treatments. Follow-up data of 387 patients were available. Significant improvement in outcome parameters (International Prostate Symptom Score [IPSS], Qmax, and PVR) was observed in comparison with baseline measurements for the three groups. PVP significantly improved the IPSS, Qmax, and PVR in patients with different PVR; PVP is a safe and effective procedure for BPH/LUTS patients.
Assuntos
Terapia a Laser/métodos , Sintomas do Trato Urinário Inferior/cirurgia , Hiperplasia Prostática/cirurgia , Retenção Urinária/cirurgia , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Cuidados Pré-Operatórios , Ressecção Transuretral da Próstata/métodos , Resultado do Tratamento , Retenção Urinária/etiologiaRESUMO
In this study, we aimed to evaluate the impact of preoperative anemia (PA) on oncological outcomes among patients with non-muscle-invasive bladder cancer (NMIBC) treated with GreenLight laser vaporization of bladder tumor (PV-BT). Between January 2010 and December 2015, 407 patients with NMIBC who underwent PV-BT surgery were stratified into normal and anemia groups based on the World Health Organization classification (anemia cutoff value: hemoglobin level, <13.0 m g/dL in men and <12.0 mg/dL in women). The Student's t test and chi-square test were performed to assess the effects of PA on clinical and pathological characteristics of patients with NMIBC. The Kaplan-Meier method was used to investigate the influence of PA on oncological survival outcomes. Before PV-BT, 139 patients (34.2%) were anemic. No significant differences in age, sex, smoking habit, tumor size, focality, grade, and stage were found between the anemia and normal groups. At a median follow-up period of 32.5 months (range, 8-60 months), 74 patients (18.2%) had urothelial recurrence, 30 (7.4%) died from any cause, and 21 (5.2%) died from bladder cancer. In the Kaplan-Meier analysis, preoperative anemia was significantly associated with decreased cancer-specific survival (CSS) and overall survival (OS) of the patients with NMIBC. However, recurrence-free survival (RFS) showed no statistically significant difference between the PA and normal groups. The preoperative anemic patients with NMIBC who underwent PV-BT surgery had worse CSS and OS. PA can be a useful and cost-effective prognostic marker in the clinical practice for NMIBC treatment.
Assuntos
Anemia/complicações , Terapia a Laser/métodos , Músculos/patologia , Cuidados Pré-Operatórios , Neoplasias da Bexiga Urinária/complicações , Neoplasias da Bexiga Urinária/cirurgia , Idoso , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Recidiva Local de Neoplasia/patologia , Prognóstico , Neoplasias da Bexiga Urinária/patologiaAssuntos
Abscesso Encefálico/diagnóstico , Trombose do Corpo Cavernoso/diagnóstico , Sinusite Esfenoidal/diagnóstico , Adulto , Anticoagulantes/uso terapêutico , Abscesso Encefálico/complicações , Abscesso Encefálico/etiologia , Trombose do Corpo Cavernoso/tratamento farmacológico , Trombose do Corpo Cavernoso/etiologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Sinusite Esfenoidal/complicaçõesRESUMO
Both commensal bacteria and infiltrating inflammatory cells play essential roles in the pathogenesis of inflammatory bowel disease. The molecular mechanisms whereby these pathogenic factors are regulated during the disease are not fully understood. We report in this article that a member of the TNF-α-induced protein 8 (TNFAIP8) family called TIPE2 (TNFAIP8-like 2) plays a crucial role in regulating commensal bacteria dissemination and inflammatory cell function in experimental colitis induced by dextran sodium sulfate (DSS). Following DSS treatment, TIPE2-deficient mice, or chimeric mice that are deficient in TIPE2 only in their hematopoietic cells, lost less body weight and survived longer than wild-type controls. Consistent with this clinical observation, TIPE2-deficient mice exhibited significantly less severe colitis and colonic damage. This was associated with a marked reduction in the colonic expression of inflammatory cytokines, such as TNF-α, IL-6, and IL-12. Importantly, the ameliorated DSS-induced colitis in TIPE2(-/-) mice also was associated with reduced local dissemination of commensal bacteria and a weaker systemic inflammatory response. Combined with our previous report that TIPE2 is a negative regulator of antibacterial immunity, these results indicate that TIPE2 promotes colitis by inhibiting mucosal immunity to commensal bacteria.
Assuntos
Colite/genética , Peptídeos e Proteínas de Sinalização Intracelular/deficiência , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Animais , Bactérias/genética , Colite/induzido quimicamente , Colite/patologia , Colo/efeitos dos fármacos , Colo/microbiologia , Colo/patologia , Células-Tronco Hematopoéticas/imunologia , Células-Tronco Hematopoéticas/microbiologia , Células-Tronco Hematopoéticas/patologia , Inflamação/imunologia , Inflamação/patologia , Inflamação/prevenção & controle , Peptídeos e Proteínas de Sinalização Intracelular/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Quimera por Radiação , Sulfatos/toxicidadeRESUMO
Phagocytosis and oxidative burst are two major effector arms of innate immunity. Although it is known that both are activated by Toll-like receptors (TLRs) and Rac GTPases, how their strengths are controlled in quiescent and TLR-activated cells is not clear. We report here that TIPE2 (TNFAIP8L2) serves as a negative regulator of innate immunity by linking TLRs to Rac. TLRs control the expression levels of TIPE2, which in turn dictates the strengths of phagocytosis and oxidative burst by binding to and blocking Rac GTPases. Consequently, TIPE2 knockout cells have enhanced phagocytic and bactericidal activities and TIPE2 knockout mice are resistant to bacterial infection. Thus, TIPE2 sets the strengths of phagocytosis and oxidative burst and may be targeted to effectively control infections.
Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Fagocitose , Explosão Respiratória/imunologia , Motivos de Aminoácidos , Animais , Linhagem Celular , Membrana Celular/metabolismo , Cruzamentos Genéticos , Humanos , Hidrólise , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Macrófagos/citologia , Macrófagos/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , Transporte Proteico , Receptores Toll-Like/metabolismo , Proteínas rac de Ligação ao GTP/metabolismoRESUMO
RNA receptors such as TLR3 and retinoid acid-inducible gene I/melanoma differentiation-associated gene 5 play essential roles in innate immunity to RNA viruses. However, how innate immunity to RNAs is controlled at the molecular level is not well understood. We describe in this study a new regulatory pathway of anti-RNA immunity that is composed of PI3K, its target GTPase Rac, and the newly described immune regulator TNF-α-induced protein 8 like-2 (TIPE2, or TNFAIP8L2). Polyinosinic-polycytidylic acid [Poly (I:C)], a dsRNA receptor ligand, activates Rac via its guanine nucleotide exchange factor Tiam; this leads to the activation of cytokine genes and, paradoxically, downregulation of the Tipe2 gene. TIPE2 is a negative regulator of immunity; its deficiency leads to hyperactivation of the PI3K-Rac pathway as exemplified by enhanced AKT, Rac, P21-activated kinase, and IFN regulatory factor 3 activities. As a consequence, TIPE2 knockout myeloid cells are hyperreactive to Poly (I:C) stimulation, and TIPE2 knockout mice are hypersensitive to Poly (I:C)-induced lethality. These results indicate that TIPE2 controls innate immunity to RNA by targeting the PI3K-Rac pathway. Therefore, manipulating TIPE2 or Rac functions can be effective for controlling RNA viral infections.
Assuntos
Imunidade Inata , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Fosfatidilinositol 3-Quinase/fisiologia , Transdução de Sinais/imunologia , Proteínas rac de Ligação ao GTP/metabolismo , Animais , Células Cultivadas , Células HEK293 , Humanos , Imunidade Inata/genética , Peptídeos e Proteínas de Sinalização Intracelular/deficiência , Peptídeos e Proteínas de Sinalização Intracelular/genética , Células L , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Inibidores de Fosfoinositídeo-3 Quinase , Poli I-C/antagonistas & inibidores , Poli I-C/farmacologia , Transdução de Sinais/genética , Proteínas rac de Ligação ao GTP/antagonistas & inibidores , Proteínas rac de Ligação ao GTP/fisiologiaRESUMO
Tissue infiltration by circulating leukocytes via directed migration (also referred to as chemotaxis) is a common pathogenic mechanism of inflammatory diseases. G protein-coupled receptors (GPCRs) are essential for sensing chemokine gradients and directing the movement of leukocytes during immune responses. The tumor necrosis factor α-induced protein 8-like (TIPE or TNFAIP8L) family of proteins are newly described pilot proteins that control directed migration of murine leukocytes. However, how leukocytes integrate site-specific directional cues, such as chemokine gradients, and utilize GPCR and TIPE proteins to make directional decisions are not well understood. Using both gene knockdown and biochemical methods, we demonstrated here that 2 human TIPE family members, TNFAIP8 and TIPE2, were essential for directed migration of human CD4+ T cells. T cells deficient in both of these proteins completely lost their directionality. TNFAIP8 interacted with the Gαi subunit of heterotrimeric (α, ß, γ) G proteins, whereas TIPE2 bound to PIP2 and PIP3 to spatiotemporally control immune cell migration. Using deletion and site-directed mutagenesis, we established that Gαi interacted with TNFAIP8 through its C-terminal amino acids, and that TIPE2 protein interacted with PIP2 and PIP3 through its positively charged amino acids on the α0 helix and at the grip-like entrance. We also discovered that TIPE protein membrane translocation (i.e. crucial for sensing chemokine gradients) was dependent on PIP2. Collectively, our work describes a new mechanistic paradigm for how human T cells integrate GPCR and phospholipid signaling pathways to control directed migration. These findings have implications for therapeutically targeting TIPE proteins in human inflammatory and autoimmune diseases.
Assuntos
Sistemas do Segundo Mensageiro , Transdução de Sinais , Humanos , Animais , Camundongos , Quimiocinas , Aminoácidos , Lipídeos , Peptídeos e Proteínas de Sinalização IntracelularRESUMO
OBJECTIVE: TNFAIP8 and TIPE2 belong to TNFa-induced protein 8 (TNFAIP8/TIPE) family. They control apoptosis and direct leukocyte migration. Nucleus pulposus (NP) cell loss is a hallmark of intervertebral disc (IVD) degeneration in response to injury, and inflammation may cause pain. Here, we examined the effects of TNFAIP8/TIPE2 deficiency on the IVDs in mice with these genes deleted. DESIGN: Tail IVDs in Tnfaip8 or Tipe2 single and double knockout mice (Tnfaip8-/-, Tipe2-/-, and Tnfaip8/Tipe2 dko), and wild type (WT) controls were injured. The spine motion segments were stained with Safranin O to reveal proteoglycans. Macrophages were identified by immunostaining, and selected inflammatory marker and collagen gene expression was examined by Real Time PCR. RESULTS: The injured tail IVDs of Tnfaip-/-, Tipe2-/-, and Tnfaip8/Tipe2 dko mice all displayed higher levels of proteoglycans than WT controls. Fewer macrophages were found in the injured IVDs of Tipe2-/- and Tnfaip8/Tipe2 dko mice than WT. Il6, Adam8 and Col1 gene expression was downregulated in the injured IVDs of Tnfip8/Tipe2 dko mice. CONCLUSIONS: TNFAIP8 and TIPE2 loss of function ameliorated proteoglycan loss and inflammation in the injured IVDs. They may serve as molecular targets to preserve disc structure and reduce inflammation.
RESUMO
BACKGROUND: Probiotics have been used in livestock production for many years, but information on their benefits during the early life of calves is inconsistent. This study aimed to assess the effects of probiotics on the performance of pre-weaning dairy calves and identify the factors influencing their effect sizes. RESULTS: Forty-nine studies were selected for meta-analysis based on the inclusion and exclusion criteria. The study qualities were evaluated using a predefined risk assessment tool following GRADE guidelines. Meta-analysis results showed that probiotics increased the growth performance (body weight by 1.988 kg and average daily gain by 40.689 g/d), decreased digestibility and feed efficiency (feed conversion rate by 0.073), altered rumen parameter (decreased acetate by 2.815 mmol/L and increased butyrate by 0.788 mmol/L), altered blood parameter (decreased AST by 4.188 U/L, increased BHBA by 0.029 mmol/L and IgG by 0.698 g/L), increased faecal parameter (faecal bacteria counts by 0.680 log10 CFU/g), based on the strict criteria (PSMD < 0.05, I2 < 50%). Additionally, probiotics increased digestibility and feed efficiency (starter dry matter intake by 0.034 kg/d and total dry matter intake by 0.020 kg/d), altered blood parameter (increased IgA by 0.313 g/L, IgM by 0.262 g/L, and total antioxidant capacity by 0.441 U/mL, decreased MDA by 0.404 nmol/mL), decreased faecal parameter (faecal score by 0.052), based on the loose criteria (PSMD < 0.05, I2 > 50%). Regression and sub-group analyses showed that probiotic strains, supplementation dosage, and methods significantly affected the performance of calves. The probiotics supplied with more than 9.5 log10 CFU/d significantly increased IgA and IgM contents (PSMD < 0.05). Additionally, the compound probiotics significantly increased TDMI, IgA, and IgM (PSMD ≤ 0.001). Furthermore, probiotics supplemented in liquid (whole milk or milk replacer) significantly increased TDMI and decreased faecal score (PSMD < 0.05), while in whole milk, they significantly increased body weight, IgA, and IgM (PSMD < 0.001). CONCLUSIONS: Probiotics could improve the growth performance, feed intake and efficiency, rumen fermentation, immune and antioxidant capacity, and health of pre-weaning calves. However, the effect sizes were related to the dosage, composition, and supplementation methods of probiotics.
RESUMO
A man diagnosed as TAFRO syndrome was successfully responded to a novel immunosuppressive regimen containing methylprednisolone and mycophenolate mofetil. Blood cells firstly recovered, followed by the general situation and complete recover 1 month later, highlighting the danger of TAFRO syndrome and the importance of immunosuppressive agents in reversing pathological course.
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OBJECTIVES: The early molecular events after intervertebral disc injury remain unclear. In this study, we aimed to compare inflammatory markers from 1 day to 4 wks after injury to have a comprehensive understanding of the intervertebral disc response to injury. DESIGN: Mouse tail intervertebral disc injury was induced by a needle puncture. Inflammatory marker gene expression and morphological changes were recorded at 1 day, 1 wk, and 4 wks after injury. RESULTS: Tnfa , Il6 , and Cxcl1 gene expression peaked at day 1 post-needle puncture of the mouse intervertebral disc, Adam8 gene expression peaked at 1-wk time point, while Tipe2 gene expression was upregulated at week 4 postinjury. F4/80 positive cells, likely to be macrophages, are present as early as day 1 in the injured intervertebral discs and consistently present at week 4 postinjury. Loss of Safranin O staining and increased histological scores of the injured intervertebral discs are consistent with progressive degeneration after injury. CONCLUSIONS: Inflammatory cytokines including Tnfa precede Tipe2 , suggesting that Tipe2 is likely induced by Tnfa . Upregulation of Adam8 and Cxcl1 gene expression persisted at week 4, suggesting that they play a role in the transition to chronic phase of intervertebral disc degeneration.
Assuntos
Degeneração do Disco Intervertebral , Disco Intervertebral , Traumatismos da Coluna Vertebral , Camundongos , Animais , Cauda/lesões , Degeneração do Disco Intervertebral/patologia , Disco Intervertebral/lesões , Agulhas , Modelos Animais de Doenças , Proteínas de Membrana/genética , Antígenos CD/metabolismo , Proteínas ADAM/metabolismoRESUMO
Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population of leukocytes that are important for tumorigenesis and tumor immunotherapy. They comprise up to 10% of leukocytes in the blood of tumor patients and their depletion may be required for successful tumor immunotherapy. However, the identity of MDSCs remains obscure, primarily due to their heterogeneity and lack of a known lineage-specific transcription factor specifying their differentiation. Using single-cell transcriptomics and gene knockout approaches, we now describe a subset of murine and human myeloid suppressor cells, named rel-dependent monocytes (rMos), which are programmed by the transcription factor c-Rel of the NF-κB family. Unlike MDSCs described previously, the c-Rel-dependent monocytes expressed a high amount of the proinflammatory cytokine IL-1ß together with a low level of suppressive molecule arginase 1. Both in vitro and in tumor-bearing mice, these c-Rel+ IL-1ßhi Arg1- monocytes promoted tumor growth by potently suppressing T cell function and showed a strong migratory phenotype, all of which were impaired by c-Rel deficiency or inhibition. Mechanistic studies revealed that c-Rel controlled the expression of monocyte signature genes through a unique transcriptional complex called the c-Rel enhanceosome, and IL-1ß-CCL2 crosstalk between tumor cells and the rel-dependent monocytes maintained the suppressive tumor microenvironment. Thus, c-Rel specifies the development of a suppressive monocyte population and could be selectively targeted for treating cancer.