Brummer E, Hanson L H, Stevens D A
Department of Medicine, Santa Clara Valley Medical Center, San Jose, California 95128.
Cell Immunol. 1991 Jan;132(1):236-45. doi: 10.1016/0008-8749(91)90022-4.
Peritoneal-and pulmonary macrophages can be activated in vitro with lymphokines (LK) or IFN-gamma, without exogenous lipopolysaccharide, for fungicidal activity against several pathogenic fungi. However, neither the biochemical nor metabolic events of the activation process or of the effector phase have been defined. In the present work we sought to elucidate these events with time-course studies using inhibitors of protein synthesis as well as immunosuppressive agents. We found that protein synthesis inhibitors abrogated the activation process, because cycloheximide (CHX) (1-2 micrograms/ml) prevented activation of macrophages for fungicidal activity against Candida albicans, Blastomyces dermatitidis, and Paracoccidioides brasiliensis. Blocking of the activation process by CHX was not due to macrophage cytotoxicity, and CHX did not impair the ability of nonactivated macrophages to kill Candida parapsilosis. In kinetic studies we showed that activation of macrophages was induced in 4 hr of LK treatment and that CHX had no effect if added after this time. In contrast to CHX, therapeutic concentrations of hydrocortisone (HC), such as less than or equal to 5 micrograms/ml, or cyclosporin A (CsA), 5 micrograms/ml, did not significantly inhibit LK activation of macrophages for killing of fungi. In the effector phase, the fungicidal capacity of activated macrophages in short-term (less than or equal to 4 hr) killing assays could not be abrogated by CHX (5 micrograms/ml), HC (100 micrograms/ml), or CsA (10 micrograms/ml). These results demonstrate that the activation but not the effector mechanism of macrophages for fungicidal activity is blocked by inhibition of protein synthesis. In contrast, therapeutic concentrations of HC or CsA may not interfere with activation of macrophages or their killing mechanisms, thus providing a rationale for antifungal immunotherapy in certain clinical situations (e.g., infection in the immunosuppressed patient).
腹膜巨噬细胞和肺巨噬细胞可在体外被淋巴因子（LK）或γ干扰素激活，无需外源性脂多糖，从而获得针对多种致病真菌的杀真菌活性。然而，激活过程或效应阶段的生化及代谢事件均未明确。在本研究中，我们试图通过使用蛋白质合成抑制剂以及免疫抑制剂进行时间进程研究来阐明这些事件。我们发现蛋白质合成抑制剂可废除激活过程，因为环己酰亚胺（CHX）（1 - 2微克/毫升）可阻止巨噬细胞被激活以获得针对白色念珠菌、皮炎芽生菌和巴西副球孢子菌的杀真菌活性。CHX对激活过程的阻断并非由于巨噬细胞毒性，且CHX不会损害未激活巨噬细胞杀灭近平滑念珠菌的能力。在动力学研究中，我们表明LK处理4小时可诱导巨噬细胞激活，且在此时间之后添加CHX则无作用。与CHX相反，治疗浓度的氢化可的松（HC），如小于或等于5微克/毫升，或环孢素A（CsA），5微克/毫升，并不会显著抑制LK激活巨噬细胞以杀灭真菌。在效应阶段，CHX（5微克/毫升）、HC（100微克/毫升）或CsA（10微克/毫升）无法废除激活巨噬细胞在短期（小于或等于4小时）杀伤试验中的杀真菌能力。这些结果表明，抑制蛋白质合成可阻断巨噬细胞的激活机制，但不会阻断其杀真菌活性的效应机制。相比之下，治疗浓度的HC或CsA可能不会干扰巨噬细胞的激活或其杀伤机制，从而为某些临床情况（如免疫抑制患者的感染）中的抗真菌免疫治疗提供了理论依据。
