Thompson H L, Wilton J M
Medical Research Council Dental Research Unit, London Hospital Medical College, United Kingdom.
Infect Immun. 1991 Mar;59(3):932-40. doi: 10.1128/iai.59.3.932-940.1991.
Human polymorphonuclear leukocytes (PMN) were able to generate and release superoxide anions upon stimulation of Streptococcus mutans, Bacteroides gingivalis, and Capnocytophaga ochracea when incubated aerobically but not when incubated anaerobically. Lysozyme release and phagocytosis by PMN were independent of oxygen, and no difference between PMN incubated aerobically or anaerobically was observed (PMN stimulated by B. gingivalis released 7.6% total lysozyme when aerobic and 6.9% when anaerobic). There were variations in lysozyme release and phagocytosis for the three organisms, particularly for phagocytosis. B. gingivalis and C. ochracea yielded lower phagocytosis values than those for S. mutans, e.g., at 1 h 67% of the initial inoculum of S. mutans was phagocytosed (versus only 40% for B. gingivalis). Transmission electron microscopy showed that both S. mutans and B. gingivalis were internalized into classical phagolysosomes. In contrast, C. ochracea showed two forms of internalization; C. ochracea either formed a classical phagolysosome or was tightly bound in the cytoplasm with no surrounding cell membrane. Intracellular killing of S. mutans and C. ochracea was unaffected by anaerobiosis, but killing of C. ochracea was much lower than that of S. mutans (1 x 10(7) to 2 x 10(7) bacteria killed compared with 5.1 x 10(7) bacteria killed at 6 h). In contrast, a greater number of B. gingivalis was killed in the presence of oxygen (5.3 x 10(7) bacteria were killed when aerobically incubated and 1.9 x 10(7) bacteria were killed when anaerobically incubated). These results suggest that the ability to survive anaerobically may enable some bacteria to evade PMN killing; however, abnormal phagocytosis may represent a more efficient way to evade both oxygen-dependent and -independent killing mechanisms, leading to enhanced virulence of the organism.
人类多形核白细胞（PMN）在需氧培养时，受到变形链球菌、牙龈卟啉单胞菌和黄褐二氧化碳嗜纤维菌刺激后能够产生并释放超氧阴离子，但在厌氧培养时则不能。PMN释放溶菌酶和进行吞噬作用与氧气无关，需氧培养和厌氧培养的PMN之间未观察到差异（牙龈卟啉单胞菌刺激的PMN在需氧时释放7.6%的总溶菌酶，厌氧时释放6.9%）。这三种微生物的溶菌酶释放和吞噬作用存在差异，尤其是吞噬作用。牙龈卟啉单胞菌和黄褐二氧化碳嗜纤维菌的吞噬值低于变形链球菌，例如，在1小时时，变形链球菌初始接种物的67%被吞噬（而牙龈卟啉单胞菌仅为40%）。透射电子显微镜显示，变形链球菌和牙龈卟啉单胞菌均被内化到经典吞噬溶酶体中。相比之下，黄褐二氧化碳嗜纤维菌表现出两种内化形式；黄褐二氧化碳嗜纤维菌要么形成经典吞噬溶酶体，要么紧密结合在细胞质中，周围没有细胞膜。变形链球菌和黄褐二氧化碳嗜纤维菌的细胞内杀伤不受厌氧状态影响，但黄褐二氧化碳嗜纤维菌的杀伤率远低于变形链球菌（6小时时，杀死1×10⁷至2×10⁷个细菌，而变形链球菌为5.1×10⁷个）。相比之下，在有氧条件下杀死的牙龈卟啉单胞菌数量更多（需氧培养时杀死5.3×10⁷个细菌，厌氧培养时杀死1.9×10⁷个细菌）。这些结果表明，厌氧生存能力可能使一些细菌能够逃避PMN的杀伤；然而，异常吞噬作用可能是逃避依赖氧气和不依赖氧气的杀伤机制的更有效方式，从而导致该生物体毒力增强。
