Nordmann P, Ronco E, Guenounou M
Department of Microbiology, Paris-Ouest Medical School, Paris V University, Garches, France.
J Infect Dis. 1993 Jun;167(6):1456-9. doi: 10.1093/infdis/167.6.1456.
Rhodococcus equi is a facultative, intracellular, gram-positive coccobacillus increasingly reported as an opportunistic pathogen in AIDS patients. In vitro, splenic cells of noninfected euthymic mice produced tumor necrosis factor-alpha (TNF alpha) in greater amounts when incubated with live R. equi rather than with killed bacteria. In vivo, interferon-gamma (IFN-gamma) and TNF alpha serum levels of infected euthymic mice remained below the level of detectability. Treatment of infected nude mice, which developed chronic infection, with discontinuous injections of IFN-gamma, TNF alpha, or both did not decrease bacterial colony-forming units in liver, spleen, or lungs. However, treatment of infected euthymic mice, which cured a R. equi inoculum within 3 weeks, with anti-IFN-gamma or anti-TNF alpha antibodies (or both) significantly increased tissue colony counts. These data argue that, in this murine model, endogenous IFN-gamma and TNF alpha are involved in the cell-mediated immunologic response against R. equi infection.
马红球菌是一种兼性、细胞内寄生的革兰氏阳性球杆菌，越来越多地被报道为艾滋病患者的机会性病原体。在体外，未感染的正常胸腺小鼠的脾细胞与活的马红球菌一起孵育时，产生的肿瘤坏死因子-α（TNFα）比与死菌孵育时更多。在体内，感染的正常胸腺小鼠的干扰素-γ（IFN-γ）和TNFα血清水平仍低于可检测水平。对发生慢性感染的受感染裸鼠间断注射IFN-γ、TNFα或两者进行治疗，并未降低肝脏、脾脏或肺部的细菌集落形成单位。然而，用抗IFN-γ或抗TNFα抗体（或两者）对在3周内清除马红球菌接种物的受感染正常胸腺小鼠进行治疗，显著增加了组织菌落计数。这些数据表明，在这个小鼠模型中，内源性IFN-γ和TNFα参与了针对马红球菌感染的细胞介导免疫反应。
