Macey M G, Whiley R A, Miller L, Nagamune H
Department of Haematology, Barts and the London NHS Trust, United Kingdom.
Infect Immun. 2001 Oct;69(10):6102-9. doi: 10.1128/IAI.69.10.6102-6109.2001.
Streptococcus intermedius is a member of the normal flora of the mouth but is also an opportunistic pathogen associated with purulent infections at oral and nonoral sites. Intermedilysin (ILY) has been shown to be a cytolysin capable of generating pores in the cell membrane of erythrocytes demonstrable by electron microscopy. This effect has been shown to be specific for human cells. Since polymorphonuclear cells (PMNs) are the main cell involved in innate immunity we investigated the effect of purified intermedilysin from Streptococcus intermedius on PMN function. Active ILY at a concentration of 40 ng/microl caused a significant decrease in the number of intact PMNs after 60 min. The active cytolysin, when compared with heat-inactivated ILY, did not appear to be chemotactic for the PMNs but did cause an increase in intracellular calcium, with increased cell surface CD11b expression, metabolic burst, and phagocytosis of Staphylococcus aureus. These findings may have implications for the role of ILY in deep-seated abscesses.
中间型链球菌是口腔正常菌群的一员，但也是一种与口腔及非口腔部位化脓性感染相关的机会致病菌。中间型溶素（ILY）已被证明是一种细胞溶素，能够在红细胞细胞膜上形成孔道，这可通过电子显微镜观察到。这种作用已被证明对人类细胞具有特异性。由于多形核细胞（PMN）是先天免疫的主要参与细胞，我们研究了从中间型链球菌中纯化的中间型溶素对PMN功能的影响。浓度为40 ng/微升的活性ILY在60分钟后导致完整PMN数量显著减少。与热灭活的ILY相比，活性细胞溶素似乎对PMN没有趋化作用，但确实导致细胞内钙增加，同时细胞表面CD11b表达增加、代谢爆发以及对金黄色葡萄球菌的吞噬作用增强。这些发现可能对ILY在深部脓肿中的作用具有启示意义。
