目的:探讨通过阻断花生四烯酸(arachidonic acid,AA)代谢途径抑制胰腺癌细胞增殖.方法:将胰腺癌细胞SW1990分为对照组,M K886干预组、塞莱昔布(C e l e c o x i b)干预组,MK886+Celecoxib干预组,用RT-PCR法检测细胞白三烯B4受体1(leukot...目的:探讨通过阻断花生四烯酸(arachidonic acid,AA)代谢途径抑制胰腺癌细胞增殖.方法:将胰腺癌细胞SW1990分为对照组,M K886干预组、塞莱昔布(C e l e c o x i b)干预组,MK886+Celecoxib干预组,用RT-PCR法检测细胞白三烯B4受体1(leukotriene B4receptor 1,BLT1)mRNA,血管内皮生长因子(vascular endothelial growth factor,VEGF)mRNA的表达量变化,用Western blot检测磷酸化-Erk(phosphorylated-extracellular regulated protein,p-Erk)表达量变化.结果:MK886作用下,BLT1 mRNA、VEGF mRNA等表达量均减少(P<0.01),p-Erk表达量明显减少(P<0.05),Celecoxib作用下,VEGF mRNA表达量明显减少(P<0.01),BLT1 mRNA表达与对照组无明显差异,p-Erk表达量与MK886组比较明显增加(P<0.01),MK886+80?mol/L Celecoxib作用下,BLT1 mRNA、VEGF mRNA表达量明显减少(P<0.01),p-Erk表达量与对照组无明显差异.结论:花生四烯酸的两条代谢途径均与胰腺癌的发生及增殖均有密切关系,而抑制5-脂氧合酶(5-lipoxygenase)途径较环氧化酶2(cyclooxygenase 2)途径相比,抑制肿瘤细胞增殖作用更强.展开更多
Invasive fungal infections are life-threatening,and neutrophils are vital cells of the innate immune system that defend against them.The role of LTA4H-LTB_(4)-BLT1 axis in regulation of neutrophil responses to fungal ...Invasive fungal infections are life-threatening,and neutrophils are vital cells of the innate immune system that defend against them.The role of LTA4H-LTB_(4)-BLT1 axis in regulation of neutrophil responses to fungal infection remains poorly understood.Here,we demonstrated that the LTA4H-LTB_(4)-BLT1 axis protects the host against Candida albicans and Aspergillus fumigatus,but not Cryptococcus neoformans infection,by regulating the antifungal activity of neutrophils.Our results show that deleting Lta4h or Blt1 substantially impairs the fungal-specific phagocytic capacity of neutrophils.Moreover,defective activation of the spleen tyrosine kinase(Syk)and extracellular signal-related kinase(ERK1/2)pathways in neutrophils accompanies this impairment.Mechanistically,BLT1 regulates CR3-mediated,β-1,3-glucan-induced neutrophil phagocytosis,while a physical interaction with CR3 with slight influence on its dynamics is observed.Our findings thus demonstrate that the LTA4H-LTB_(4)-BLT1 axis is essential for the phagocytic function of neutrophils in host antifungal immune response against Candida albicans and Aspergillus fumigatus.展开更多
Leukotriene B4(LTB4)receptor 1(BLT1)is a chemotactic G protein-coupled receptor expressed by leukocytes,such as granulocytes,macrophages,and activated T cells.Although there is growing evidence that BLT1 plays crucial...Leukotriene B4(LTB4)receptor 1(BLT1)is a chemotactic G protein-coupled receptor expressed by leukocytes,such as granulocytes,macrophages,and activated T cells.Although there is growing evidence that BLT1 plays crucial roles in immune responses,its role in dendritic cells remains largely unknown.Here,we identified novel DC subsets defined by the expression of BLT1,namely,BLT1hi and BLT1lo DCs.We also found that BLT1hi and BLT1lo DCs differentially migrated toward LTB4 and CCL21,a lymph node-homing chemoattractant,respectively.By generating LTB4-producing enzyme LTA4H knockout mice and CD11c promoter-driven Cre recombinase-expressing BLT1 conditional knockout(BLT1 cKO)mice,we showed that the migration of BLT1hi DCs exacerbated allergic contact dermatitis.Comprehensive transcriptome analysis revealed that BLT1hi DCs preferentially induced Th1 differentiation by upregulating IL-12p35 expression,whereas BLT1lo DCs accelerated T cell proliferation by producing IL-2.Collectively,the data reveal an unexpected role for BLT1 as a novel DC subset marker and provide novel insights into the role of the LTB4-BLT1 axis in the spatiotemporal regulation of distinct DC subsets.展开更多
文摘目的:探讨通过阻断花生四烯酸(arachidonic acid,AA)代谢途径抑制胰腺癌细胞增殖.方法:将胰腺癌细胞SW1990分为对照组,M K886干预组、塞莱昔布(C e l e c o x i b)干预组,MK886+Celecoxib干预组,用RT-PCR法检测细胞白三烯B4受体1(leukotriene B4receptor 1,BLT1)mRNA,血管内皮生长因子(vascular endothelial growth factor,VEGF)mRNA的表达量变化,用Western blot检测磷酸化-Erk(phosphorylated-extracellular regulated protein,p-Erk)表达量变化.结果:MK886作用下,BLT1 mRNA、VEGF mRNA等表达量均减少(P<0.01),p-Erk表达量明显减少(P<0.05),Celecoxib作用下,VEGF mRNA表达量明显减少(P<0.01),BLT1 mRNA表达与对照组无明显差异,p-Erk表达量与MK886组比较明显增加(P<0.01),MK886+80?mol/L Celecoxib作用下,BLT1 mRNA、VEGF mRNA表达量明显减少(P<0.01),p-Erk表达量与对照组无明显差异.结论:花生四烯酸的两条代谢途径均与胰腺癌的发生及增殖均有密切关系,而抑制5-脂氧合酶(5-lipoxygenase)途径较环氧化酶2(cyclooxygenase 2)途径相比,抑制肿瘤细胞增殖作用更强.
基金supported by the National Key Research and Development Program of China(2019YFA0508502 to XL)National Natural Science Foundation of China(31930039,31821003,91942303 to XL)+1 种基金the General Financial Grant from the China Postdoctoral Science Foundation(2020M670301 to YX)annual funding from Tsinghua University-Peking University Jointed Center for Life Sciences.
文摘Invasive fungal infections are life-threatening,and neutrophils are vital cells of the innate immune system that defend against them.The role of LTA4H-LTB_(4)-BLT1 axis in regulation of neutrophil responses to fungal infection remains poorly understood.Here,we demonstrated that the LTA4H-LTB_(4)-BLT1 axis protects the host against Candida albicans and Aspergillus fumigatus,but not Cryptococcus neoformans infection,by regulating the antifungal activity of neutrophils.Our results show that deleting Lta4h or Blt1 substantially impairs the fungal-specific phagocytic capacity of neutrophils.Moreover,defective activation of the spleen tyrosine kinase(Syk)and extracellular signal-related kinase(ERK1/2)pathways in neutrophils accompanies this impairment.Mechanistically,BLT1 regulates CR3-mediated,β-1,3-glucan-induced neutrophil phagocytosis,while a physical interaction with CR3 with slight influence on its dynamics is observed.Our findings thus demonstrate that the LTA4H-LTB_(4)-BLT1 axis is essential for the phagocytic function of neutrophils in host antifungal immune response against Candida albicans and Aspergillus fumigatus.
基金supported by Grants-in-Aid for Scientific Research(KAKENHI)from the Ministry of Education,Culture,Sports,Science,and Technology(MEXT)of the Japan Society for the Promotion of Science(grant numbers JP22116001,JP22116002,JP15H05901,JP15H05904,JP15H04708,and JP18H02627 to T.Y.JP25860223,JP15K19032 and JP17K08664 to T.K.+1 种基金JP15K08316 and JP18K06923 to K.S.and JP15KK0320 and JP16K08596 to T.O.),by AMED-CREST(JP20gm12l0006 to K.S.)and by grants from the Naito Foundation,the Ono Medical Research Foundation,the Uehara Memorial Foundation,the Mitsubishi Foundation,and the Takeda Science Foundation.The study was also supported(in part)by a Grant-in-Aid(S1311011 to T.Y.)from the Foundation for Strategic Research Projects in Private Universities of the MEXT and by a grant from the Institute for Environmental and Gender-Specific Medicine.We thank the Research Center for Human Disease Modeling(Kyushu University)and the Research Support Center of the Division of Molecular and Biochemical Research(Juntendo University)for providing technical support.
文摘Leukotriene B4(LTB4)receptor 1(BLT1)is a chemotactic G protein-coupled receptor expressed by leukocytes,such as granulocytes,macrophages,and activated T cells.Although there is growing evidence that BLT1 plays crucial roles in immune responses,its role in dendritic cells remains largely unknown.Here,we identified novel DC subsets defined by the expression of BLT1,namely,BLT1hi and BLT1lo DCs.We also found that BLT1hi and BLT1lo DCs differentially migrated toward LTB4 and CCL21,a lymph node-homing chemoattractant,respectively.By generating LTB4-producing enzyme LTA4H knockout mice and CD11c promoter-driven Cre recombinase-expressing BLT1 conditional knockout(BLT1 cKO)mice,we showed that the migration of BLT1hi DCs exacerbated allergic contact dermatitis.Comprehensive transcriptome analysis revealed that BLT1hi DCs preferentially induced Th1 differentiation by upregulating IL-12p35 expression,whereas BLT1lo DCs accelerated T cell proliferation by producing IL-2.Collectively,the data reveal an unexpected role for BLT1 as a novel DC subset marker and provide novel insights into the role of the LTB4-BLT1 axis in the spatiotemporal regulation of distinct DC subsets.
