Lam C, Mathison G E
J Med Microbiol. 1983 Aug;16(3):309-16. doi: 10.1099/00222615-16-3-309.
The ability of aminoglycoside antibiotics and rifampicin to kill Staphylococcus aureus that had been ingested by blood polymorphonuclear leukocytes (PMNs) in vitro was investigated. Gentamicin and streptomycin failed to kill intracellular staphylococci, possibly because they could not penetrate PMNs or were inactivated by the low intraphagolysosomal pH. Rifampicin accumulated within the leukocytes in a form that killed staphylococci in a cell-free medium, but the bactericidal activity of intracellular rifampicin against ingested staphylococci was much less than that in a cell-free system. Investigations with granules isolated from PMNs, at various pH-values, revealed that the impairment of rifampicin activity was a result of limitation of the staphylococcal growth rate by a low pH. These observations indicate that the inhibition of intraphagocytic bacterial growth by the low intraphagolysosomal pH and other phagolysosomal bacteristatic factors determines the antimicrobial activity of accumulated antibiotics.
研究了氨基糖苷类抗生素和利福平在体外杀死被血液多形核白细胞（PMN）摄取的金黄色葡萄球菌的能力。庆大霉素和链霉素未能杀死细胞内的葡萄球菌，可能是因为它们无法穿透PMN或被吞噬溶酶体内的低pH值灭活。利福平以一种能在无细胞培养基中杀死葡萄球菌的形式在白细胞内蓄积，但细胞内利福平对摄取的葡萄球菌的杀菌活性远低于无细胞系统中的杀菌活性。在不同pH值下对从PMN分离出的颗粒进行的研究表明，利福平活性受损是由于低pH值限制了葡萄球菌的生长速度。这些观察结果表明，吞噬溶酶体内的低pH值和其他吞噬溶酶体抑菌因子对吞噬细胞内细菌生长的抑制作用决定了蓄积抗生素的抗菌活性。
