【摘要】 目的比较巨噬细胞内马尔尼菲青霉(Pm)的异柠檬酸裂解酶(ICL1)基因转录及蛋白表达水平,初步探讨乙醛酸循环在Pm致病中的意义。方法将Pm分生孢子与Raw264.7细胞共培养16份,随机分为4组:处理组(T)采用脂多糖及小鼠γ干扰素处理,处理抑制组(TI)在处理组的基础上加入一氧化氮合酶抑制剂(LNMMA),对照组(C)加入同体积的培养基,对照抑制组(CI)在对照组基础上加入LNMMA;采用实时RT-PCR法比较各组细胞内Pm的ICL1基因转录水平;采用酶催化反应检测ICL1蛋白表达及活性;采用菌落计数比较各组细胞内Pm的数量;采用化学法检测一氧化氮含量。结果C组、CI组、T组、TI组的ICL1相对转录水平分别为1.00、1.42、33.09、74.88,蛋白表达及活性分别为0.06、0.07、0.18、0.93,组间差异有统计学意义(P<0.05);处理组一氧化氮含量较其他组增高(P<0.01),菌落计数减少(P<0.01)。结论ICL1对Pm在功能抑制的巨噬细胞内的生长起着重要的作用,正常巨噬细胞产生的活性氮成分能抑制ICL1基因转录及蛋白表达,从而抑制巨噬细胞内Pm的生长。更多还原

【Abstract】 Objective To investigate the differential expression of isocitrate lyase in Penicillium marneffei phagocytized by nonstimulated and stimulated murine macrophages,and explore the role of glyoxylate pathway in pathogenesis of Penicilliosis marneffei.Methods Penicillium marneffei conidia and Raw264.7 cells were incubated in 16 cultures,which were divided to 4 groups for treatment with N-monomethyl-L-arginine(LNMMA,CI group),murine interferon-γ(IFN-γ)plus lipopolysaccharide(LPS)(T group),IFN-γ plus LPS and LNMMA(TI group),or the same volume of culture medium(C group).The transcriptional levels of isocitrate lyase were detected using real-time RT-PCR,and its expression levels detected biochemically.Results The transcriptional levels of isocitrate lyase in C,CI,T,TI groups were 1.00,1.42,33.09,and 74.88(P<0.05),while the expression levels were 0.06,0.07,0.18,and 0.93,respectively(P<0.05).The content of nitric oxide in T group was significantly higher than that in the other groups(P<0.01),but the CFU of T group was the lowest(P<0.01).Conclusion Reactive nitrogen intermediates induced by stimulated murine macrophages restrain the expression of isocitrate lyase of Penicillium marneffei and development of Penicillium marneffei,in which process the glyoxylate pathway may play an important role.更多还原