Antimicrobial actions of the NADPH phagocyte oxidase and inducible nitric oxide synthase in experimental salmonellosis. I. Effects on microbial killing by activated peritoneal macrophages in vitro.
Antimicrobial actions of the NADPH phagocyte oxidase and inducible nitric oxide synthase in experimental salmonellosis. I. Effects on microbial killing by activated peritoneal macrophages in vitro.
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DOI：
10.1084/jem.192.2.227
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发表时间：
2000-07-17
影响因子：
15.3
通讯作者：
Fang, F C
中科院分区：
文献类型：
--
作者：
Vazquez-Torres, A;Jones-Carson, J;Mastroeni, P;Ischiropoulos, H;Fang, F C
采用C57 BL/6、同源gp 91 phox −/−、iNOS −/−和双重免疫缺陷phox −/−iNOS −/−小鼠腹腔巨噬细胞，研究了NADPH吞噬细胞氧化酶（phox）和诱导型一氧化氮（NO）合酶（iNOS）对巨噬细胞抗鼠伤寒沙门氏菌抗菌活性的贡献。呼吸爆发和一氧化氮自由基（NO·）对巨噬细胞的抗沙门氏菌活性有明显的贡献。NADPH氧化酶依赖性杀伤仅限于吞噬后的最初几个小时，而iNOS有助于抗菌活性的早期和晚期。NO衍生物最初与氧自由基协同杀死S。鼠伤寒沙门氏菌，并随后发挥延长的氧化酶非依赖性抑菌作用。生化分析表明，巨噬细胞对沙门氏菌的早期杀灭与氧化化学反应相一致，其特征是超氧阴离子（O2·−）、过氧化氢（H2 O2）和过氧亚硝酸盐（ONOO−）的产生。然而，免疫荧光显微镜和使用清除剂尿酸的杀伤试验表明，过氧亚硝酸盐不负责野生型S.鼠伤寒。快速氧化细菌杀灭之后是持续的亚硝化化学，限制细菌生长。干扰素γ似乎主要通过增加NO·的产生来增强抗菌活性，尽管也观察到了小的iNOS非依赖性效应。这些发现表明，巨噬细胞杀死沙门氏菌的动态过程中，随着时间的推移而变化，并需要产生反应性氧化和亚硝化物种。
The contribution of the NADPH phagocyte oxidase (phox) and inducible nitric oxide (NO) synthase (iNOS) to the antimicrobial activity of macrophages for Salmonella typhimurium was studied by using peritoneal phagocytes from C57BL/6, congenic gp91phox −/−, iNOS −/−, and doubly immunodeficient phox −/−iNOS −/− mice. The respiratory burst and NO radical (NO·) made distinct contributions to the anti-Salmonella activity of macrophages. NADPH oxidase–dependent killing is confined to the first few hours after phagocytosis, whereas iNOS contributes to both early and late phases of antibacterial activity. NO-derived species initially synergize with oxyradicals to kill S. typhimurium, and subsequently exert prolonged oxidase-independent bacteriostatic effects. Biochemical analyses show that early killing of Salmonella by macrophages coincides with an oxidative chemistry characterized by superoxide anion (O2·−), hydrogen peroxide (H2O2), and peroxynitrite (ONOO−) production. However, immunofluorescence microscopy and killing assays using the scavenger uric acid suggest that peroxynitrite is not responsible for macrophage killing of wild-type S. typhimurium. Rapid oxidative bacterial killing is followed by a sustained period of nitrosative chemistry that limits bacterial growth. Interferon γ appears to augment antibacterial activity predominantly by enhancing NO· production, although a small iNOS-independent effect was also observed. These findings demonstrate that macrophages kill Salmonella in a dynamic process that changes over time and requires the generation of both reactive oxidative and nitrosative species.