Acidification of phagosomes in murine macrophages: blockage by Nocardia asteroides.
Acidification of phagosomes in murine macrophages: blockage by Nocardia asteroides.
复制标题
鼠巨噬细胞中吞噬体的酸化：小行星诺卡氏菌的阻塞。
DOI：
10.1093/infdis/154.6.952
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发表时间：
1986
期刊：
影响因子：
--
通讯作者：
Goldstein,E
中科院分区：
文献类型：
--
作者：
Black,CM;Paliescheskey,M;Beaman,BL;Donovan,RM;Goldstein,E
大多数星状诺卡氏菌菌株在脑心浸液中生长时对pH 5的不利影响敏感。防止吞噬体酸化可能是该生物体在巨噬细胞的杀微生物活性下存活的机制。将异硫氰酸黄绿素偶联到诺卡氏菌和放线菌表面，形成pH敏感的荧光探针。通过使用计算机化的细胞分光光度计，在单个吞噬体内定量该探针的荧光发射，从而定量pH。无论是活细胞还是死细胞。菌株GUH-2的吞噬体pH保持在pH 7以上2小时。asteroidesstrain 19247，仅部分阻断酸化。相反，当使用放线菌作为正常反应的对照时，pH值降低至约pH 5。因此，小行星阻止吞噬体酸化。因为诺卡氏菌以同样的方式杀死，这种酸化抑制似乎与细胞成分有关。这种防止吞噬体酸化的能力可能是细胞内病原体存活的先决条件。
Most strains ofNocardia asteroidesare susceptible to the detrimental effects of pH 5 when grown in buffered brain-heart infusion broth. Preventing phagosomal acidification may be a mechanism by which this organism survives the microbicidal activity of macrophages. Fluorescein isothiocyanate was conjugated to the surface ofNocardiaandSaccharomycesto form pH-sensitive fluorescent probes. The fluorescent emission, and thus the pH, of this probe was quantitated within individual phagosomes by using a computerized cytospectrophotometer. When either live or dead cells of virulentN. asteroidesstrain GUH-2 were ingested, the phagosomal pH remained above pH 7 for 2 hr. A nonpathogenic soil isolate,N. asteroidesstrain 19247, only partially blocked acidification. In contrast, whenSaccharomyceswas used as a control for normal response, the pH decreased to approximately pH 5. Therefore, virulentN. asteroidesblocks phagosomal acidification. Because killedNocardiaact in the same manner, this inhibition of acidification appears to be associated with cellular components. This capacity to prevent phagosomal acidification may be prerequisite to the survival of intracellular pathogens.