目的研究脓毒症致大鼠急性肺损伤肺组织中CD200/CD200R的表达。方法采用盲肠结扎穿孔术复制大鼠脓毒症急性肺损伤(ALI)模型,将36只大鼠随机分为急性肺损伤组和假手术组,每组设8、16、24 h 3个观察时间点,急性肺损伤组为A、B、C组,假手...目的研究脓毒症致大鼠急性肺损伤肺组织中CD200/CD200R的表达。方法采用盲肠结扎穿孔术复制大鼠脓毒症急性肺损伤(ALI)模型,将36只大鼠随机分为急性肺损伤组和假手术组,每组设8、16、24 h 3个观察时间点,急性肺损伤组为A、B、C组,假手术组与之相对应的时间点分别为D、E、F组,各组大鼠在相应的时间点行动脉血气分析、检测IL-4、肺湿/干质量比测定、肺组织病理学观察,采用RT-PCR法检测肺组织CD200/CD200R mRNA表达、免疫印迹法检测肺组织CD200/CD200R的蛋白表达。结果①CD200/CD200R蛋白及mRNA表达情况:急性肺损伤A、B组较相应对照D、E组表达显著降低(P<0.05),而急性肺损伤C组与相应对照F组比较无显著差异(P>0.05);B组较A组表达显著上升(P<0.05),C组较B组表达显著上升(P<0.05),急性肺损伤组随着病情进展CD200/CD200R的蛋白及mRNA逐渐恢复至假手术对照组水平,各组间差异有统计学意义(P<0.05);②动脉血气分析:A组较相应对照D组无显著差异(P>0.05),B、C组较相应对照E、F组显著降低(P<0.05);急性肺损伤组随着病情进展动脉血氧分压逐渐降低;③IL-4检测:A组较相应对照D组无显著差异(P>0.05),B、C组较相应对照E、F组显著升高(P<0.05),急性肺损伤组随着病情进展IL-4浓度逐渐增加,差异有统计学意义(P<0.05);④肺湿/干质量比:A组较相应对照D组无显著差异(P>0.05),B、C组较相应对照E、F组显著升高(P<0.05),急性肺损伤组随着病情进展肺湿/干质量比逐渐增加,差异有统计学意义(P<0.05);肺组织病理变化:急性肺损伤组随病情进展,病理变化逐渐加重,假手术组病理学变化不明显。结论急性肺损伤组大鼠肺组织CD200/CD200R蛋白及mRNA早期表达降低,至24 h恢复至假手组水平,IL-4呈逐渐升高趋势,参与肺损伤炎症反应,提示CD200/CD200R参与脓毒症ALI。展开更多
Distinct neutrophil populations arise during certain pathological conditions.The generation of dysfunctional neutrophils during sepsis and their contribution to septicemia-related systemic immune suppression remain un...Distinct neutrophil populations arise during certain pathological conditions.The generation of dysfunctional neutrophils during sepsis and their contribution to septicemia-related systemic immune suppression remain unclear.In this study,using an experimental sepsis model that features immunosuppression,we identified a novel population of pathogenic CD200R^(high) neutrophils that are generated during the initial stages of sepsis and contribute to systemic immune suppression by enhancing regulatory T(T_(reg))cells.Compared to their CD200R^(low)counterparts,sepsis-generated CD200Rhigh neutrophils exhibit impaired autophagy and dysfunction,with reduced chemotactic migration,superoxide anion production,and TNF-αproduction.Increased soluble CD200 blocks autophagy and neutrophil maturation in the bone marrow during experimental sepsis,and recombinant CD200 treatment in vitro can induce neutrophil dysfunction similar to that observed in CD200R^(high) neutrophils.The administration of anα-CD200R antibody effectively reversed neutrophil dysfunction by enhancing autophagy and protecting against a secondary infection challenge,leading to increased survival.Transcriptome analysis revealed that CD200R^(high) neutrophils expressed high levels of Igf1,which elicits the generation of Treg cells,while the administration of anα-CD200R antibody inhibited Treg cell generation in a secondary infection model.Taken together,our findings revealed a novel CD200R^(high) neutrophil population that mediates the pathogenesis of sepsis-induced systemic immunosuppression by generating Treg cells.展开更多
文摘目的研究脓毒症致大鼠急性肺损伤肺组织中CD200/CD200R的表达。方法采用盲肠结扎穿孔术复制大鼠脓毒症急性肺损伤(ALI)模型,将36只大鼠随机分为急性肺损伤组和假手术组,每组设8、16、24 h 3个观察时间点,急性肺损伤组为A、B、C组,假手术组与之相对应的时间点分别为D、E、F组,各组大鼠在相应的时间点行动脉血气分析、检测IL-4、肺湿/干质量比测定、肺组织病理学观察,采用RT-PCR法检测肺组织CD200/CD200R mRNA表达、免疫印迹法检测肺组织CD200/CD200R的蛋白表达。结果①CD200/CD200R蛋白及mRNA表达情况:急性肺损伤A、B组较相应对照D、E组表达显著降低(P<0.05),而急性肺损伤C组与相应对照F组比较无显著差异(P>0.05);B组较A组表达显著上升(P<0.05),C组较B组表达显著上升(P<0.05),急性肺损伤组随着病情进展CD200/CD200R的蛋白及mRNA逐渐恢复至假手术对照组水平,各组间差异有统计学意义(P<0.05);②动脉血气分析:A组较相应对照D组无显著差异(P>0.05),B、C组较相应对照E、F组显著降低(P<0.05);急性肺损伤组随着病情进展动脉血氧分压逐渐降低;③IL-4检测:A组较相应对照D组无显著差异(P>0.05),B、C组较相应对照E、F组显著升高(P<0.05),急性肺损伤组随着病情进展IL-4浓度逐渐增加,差异有统计学意义(P<0.05);④肺湿/干质量比:A组较相应对照D组无显著差异(P>0.05),B、C组较相应对照E、F组显著升高(P<0.05),急性肺损伤组随着病情进展肺湿/干质量比逐渐增加,差异有统计学意义(P<0.05);肺组织病理变化:急性肺损伤组随病情进展,病理变化逐渐加重,假手术组病理学变化不明显。结论急性肺损伤组大鼠肺组织CD200/CD200R蛋白及mRNA早期表达降低,至24 h恢复至假手组水平,IL-4呈逐渐升高趋势,参与肺损伤炎症反应,提示CD200/CD200R参与脓毒症ALI。
基金supported by Basic Science Research Program(NRF-2020M3A9D3038435,NRF-2017R1A5A1014560)the Korea Initiative for Fostering the University of Research and Innovation Program(NRF-2020M3H1A1077095)+1 种基金through the National Research Foundation of Korea(NRF)funded by the Ministry of Science,ICT and Future Planning and by a grant from the Korea Health Technology R&D Project through the Korea Health Industry Development Institute(KHIDI)funded by the Ministry of Health&Welfare,Republic of Korea(grant number:HI22C2004).
文摘Distinct neutrophil populations arise during certain pathological conditions.The generation of dysfunctional neutrophils during sepsis and their contribution to septicemia-related systemic immune suppression remain unclear.In this study,using an experimental sepsis model that features immunosuppression,we identified a novel population of pathogenic CD200R^(high) neutrophils that are generated during the initial stages of sepsis and contribute to systemic immune suppression by enhancing regulatory T(T_(reg))cells.Compared to their CD200R^(low)counterparts,sepsis-generated CD200Rhigh neutrophils exhibit impaired autophagy and dysfunction,with reduced chemotactic migration,superoxide anion production,and TNF-αproduction.Increased soluble CD200 blocks autophagy and neutrophil maturation in the bone marrow during experimental sepsis,and recombinant CD200 treatment in vitro can induce neutrophil dysfunction similar to that observed in CD200R^(high) neutrophils.The administration of anα-CD200R antibody effectively reversed neutrophil dysfunction by enhancing autophagy and protecting against a secondary infection challenge,leading to increased survival.Transcriptome analysis revealed that CD200R^(high) neutrophils expressed high levels of Igf1,which elicits the generation of Treg cells,while the administration of anα-CD200R antibody inhibited Treg cell generation in a secondary infection model.Taken together,our findings revealed a novel CD200R^(high) neutrophil population that mediates the pathogenesis of sepsis-induced systemic immunosuppression by generating Treg cells.
