Portnoy D A, Schreiber R D, Connelly P, Tilney L G
Department of Microbiology, University of Pennsylvania School of Medicine, Philadelphia, 19104.
J Exp Med. 1989 Dec 1;170(6):2141-6. doi: 10.1084/jem.170.6.2141.
The effect of rIFN-gamma and rTNF on the fate of hemolytic and nonhemolytic (hly-) Listeria monocytogenes in cultured mouse peritoneal macrophages was investigated. In untreated macrophages, approximately 80% of the hemolytic bacteria were killed during the first 2 h of incubation, but the survivors doubled between two and three times. In rIFN-gamma-treated macrophages, although the bacterial killing was identical to the controls during the first 2 h, there was no subsequent bacterial growth, and bactericidal activity continued for the duration of the experiment. rTNF has no affect by itself, but acted synergistically with rIFN-gamma to promote bacterial killing. Infected macrophages with or without rIFN-gamma were examined by EM. The results clearly showed that the role of rIFN-gamma was to prevent access of L. monocytogenes to the macrophage cytoplasm, which would prevent cell-to-cell spread of the bacteria. In addition, rIFN-gamma-treated macrophages exhibited enhanced digestive capacity of the intracellular bacteria.
研究了重组干扰素-γ（rIFN-γ）和重组肿瘤坏死因子（rTNF）对培养的小鼠腹腔巨噬细胞中溶血性和非溶血性（hly-）单核细胞增生李斯特菌命运的影响。在未处理的巨噬细胞中，约80%的溶血性细菌在孵育的最初2小时内被杀死，但存活的细菌数量在2至3小时内增加了一倍至两倍。在rIFN-γ处理的巨噬细胞中，虽然在最初2小时内细菌杀伤情况与对照相同，但随后没有细菌生长，并且杀菌活性在实验期间持续存在。rTNF本身没有作用，但与rIFN-γ协同作用以促进细菌杀伤。通过电子显微镜检查了有无rIFN-γ的感染巨噬细胞。结果清楚地表明，rIFN-γ的作用是阻止单核细胞增生李斯特菌进入巨噬细胞胞质，这将防止细菌在细胞间传播。此外，rIFN-γ处理的巨噬细胞对细胞内细菌的消化能力增强。
