Leijh P C, van Zwet T L, van Furth R
Infect Immun. 1980 Nov;30(2):421-6. doi: 10.1128/iai.30.2.421-426.1980.
This study shows that the intracellular killing of Streptococcus pyogenes, Streptococcus faecalis, and Streptococcus pneumoniae by human monocytes is stimulated by the extracellular presence of both heat-stable and heat-labile serum factors. A similar kind of stimulation of monocytes has been described in respect of catalase-positive microorganisms. However, killing of these bacteria is negligible in the absence of extracellular serum factors, whereas a large proportion of the ingested catalase-negative bacteria are killed in the absence of such extracellular stimuli. Monocytes from patients with chronic granulomatous disease, which are unable to kill Staphylococcus aureus even in the presence of extracellular serum, killed S. pyogenes equally effectively whether serum was present or absent. This index proved to be the same as that for killing by monocytes of healthy subjects in the absence of serum. Taken together, these results indicate that catalase-negative microorganisms possess some kind of suicide mechanism that leads to the death of these bacteria after their ingestion by monocytes in the absence of an extracellular stimulus. Furthermore, the mechanism by which extracellular serum stimulates intracellular killing probably involves enzymes of the O2-dependent bactericidal mechanisms of the monocytes.
本研究表明，人单核细胞对化脓性链球菌、粪肠球菌和肺炎链球菌的细胞内杀伤作用受到热稳定和热不稳定血清因子细胞外存在的刺激。关于过氧化氢酶阳性微生物，已描述了类似的单核细胞刺激情况。然而，在没有细胞外血清因子的情况下，这些细菌的杀伤作用可忽略不计，而在没有这种细胞外刺激的情况下，大部分摄入的过氧化氢酶阴性细菌会被杀死。慢性肉芽肿病患者的单核细胞即使在存在细胞外血清的情况下也无法杀死金黄色葡萄球菌，无论有无血清，这些单核细胞杀死化脓性链球菌的效果相同。该指标与无血清情况下健康受试者单核细胞的杀伤指标相同。综上所述，这些结果表明，过氧化氢酶阴性微生物具有某种自杀机制，在没有细胞外刺激的情况下，单核细胞摄入这些细菌后会导致其死亡。此外，细胞外血清刺激细胞内杀伤的机制可能涉及单核细胞依赖氧气的杀菌机制中的酶。
