Aratani Y, Kura F, Watanabe H, Akagawa H, Takano Y, Suzuki K, Maeda N, Koyama H
Kihara Institute for Biological Research, Yokohama City University, Totsuka, Yokohama 244-0813, Japan.
J Infect Dis. 2000 Oct;182(4):1276-9. doi: 10.1086/315843. Epub 2000 Sep 6.
Myeloperoxidase (MPO), which is located within neutrophils capable of producing hypochlorous acid, is active in vitro against bacteria and fungi. However, MPO-deficient persons are usually healthy. To define the in vivo contribution of MPO to early host defense against pulmonary infections, MPO-deficient and control mice were intranasally infected with various fungi and bacteria, and the number of residual microorganisms in lungs was compared 48 h later. MPO-deficient mice showed severely reduced cytotoxicity to Candida albicans, Candida tropicalis, Trichosporon asahii, and Pseudomonas aeruginosa. However, the mutant mice showed a slight but significantly delayed clearance of Aspergillus fumigatus and Klebsiella pneumoniae and had comparable levels of resistance to the wild type against Candida glabrata, Cryptococcus neoformans, Staphylococcus aureus, and Streptococcus pneumoniae. These results suggest that the MPO-dependent oxidative system is important for host defense against fungi and bacteria, although the effect varies by pathogen species.
髓过氧化物酶（MPO）位于能够产生次氯酸的中性粒细胞内，在体外对细菌和真菌具有活性。然而，MPO缺陷的人通常是健康的。为了确定MPO在体内对肺部感染早期宿主防御的贡献，将MPO缺陷小鼠和对照小鼠经鼻感染各种真菌和细菌，并在48小时后比较肺中残留微生物的数量。MPO缺陷小鼠对白色念珠菌、热带念珠菌、阿萨希毛孢子菌和铜绿假单胞菌的细胞毒性严重降低。然而，突变小鼠对烟曲霉和肺炎克雷伯菌的清除略有延迟但显著，并且对光滑念珠菌、新型隐球菌、金黄色葡萄球菌和肺炎链球菌的抗性水平与野生型相当。这些结果表明，MPO依赖的氧化系统对宿主抵御真菌和细菌很重要，尽管其效果因病原体种类而异。
