Mizgerd J P, Brain J D
Physiology Program, Harvard School of Public Health, Boston, MA 02115, USA.
Curr Microbiol. 1995 Aug;31(2):124-8. doi: 10.1007/BF00294288.
Pseudomonas aeruginosa (PA) infects hosts with compromised host defenses. An important defense mechanism is the generation of reactive oxygen species (ROS) by white blood cells (WBCs). What roles do ROS play in host defense against PA? Human WBCs killed PA in vitro, and they generated a respiratory burst as measured by the production of H2O2. ROS efficiently killed PA; in acellular assays, less than 10 mM of H2O2 or OCl- eliminated all bacteria in 90 min. However, WBCs with suppressed production of ROS (caused by hypoxia) killed PA normally. In addition, none of the antioxidants vitamin C, N-acetylcysteine, superoxide dismutase, or catalase affected PA killing by WBCs. Thus, PA stimulates WBCs to produce ROS, which can kill the bacteria, but disturbances of WBC ROS production do not interfere with the killing of PA. WBCs have robust, redundant mechanisms for PA elimination.
铜绿假单胞菌（PA）会感染宿主防御功能受损的宿主。一种重要的防御机制是白细胞（WBC）产生活性氧（ROS）。ROS在宿主抵御PA的过程中发挥着什么作用呢？人类白细胞在体外可杀死PA，并且通过检测过氧化氢（H2O2）的产生来衡量，它们会产生呼吸爆发。ROS能有效杀死PA；在无细胞试验中，低于10 mM的H2O2或次氯酸根离子（OCl-）在90分钟内就能消灭所有细菌。然而，ROS产生受抑制（由缺氧导致）的白细胞仍能正常杀死PA。此外，抗氧化剂维生素C、N - 乙酰半胱氨酸、超氧化物歧化酶或过氧化氢酶均不影响白细胞对PA的杀伤作用。因此，PA刺激白细胞产生活性氧，活性氧可杀死细菌，但白细胞活性氧产生的紊乱并不干扰对PA的杀伤。白细胞具有强大且冗余的PA清除机制。
