Sixbey J W, Fields B T, Sun C N, Clark R A, Nolan C M
Infect Immun. 1979 Jan;23(1):41-4. doi: 10.1128/iai.23.1.41-44.1979.
We studied interactions in vitro between human granulocytes and the yeast-like form of Blastomyces dermatitidis, because granulocytes are prominent in the host response to systemic blastomycosis. In Boyden chamber assays, broth culture filtrates of B. dermatitidis contained levels of granulocyte chemotactic activity that were significantly higher than those present in similar culture filtrates of Histoplasma capsulatum and Cryptococcus neoformans, two fungi that characteristically do not elicit granulocytes in infected tissues. Microscopic study, including electron microscopy, demonstrated that granulocytes phagocytosed B. dermatitidis promptly and efficiently. Moreover, granulocytes emitted light (chemiluminescence) at a brisk rate during phagocytosis of B. dermatitidis, indicating activation of intracellular metabolic pathways. However, fungicidal assay showed that granulocytes (1:1 cell-yeast ratio, 10% serum) killed only 29% of the B. dermatitidis inoculum during 3 h of incubation. Taken together, these findings suggest that there is disparity between phagocytosis and intracellular killing of B. dermatitidis by human granulocytes, perhaps because of resistance of this fungus to granulocyte microbicidal mechanisms.
我们研究了人类粒细胞与皮炎芽生菌酵母样形态在体外的相互作用，因为粒细胞在宿主对系统性芽生菌病的反应中很突出。在博伊登小室试验中，皮炎芽生菌的肉汤培养滤液所含的粒细胞趋化活性水平显著高于荚膜组织胞浆菌和新型隐球菌的类似培养滤液，后两种真菌在感染组织中通常不会引发粒细胞反应。包括电子显微镜在内的显微镜研究表明，粒细胞能迅速且有效地吞噬皮炎芽生菌。此外，粒细胞在吞噬皮炎芽生菌的过程中快速发出光（化学发光），表明细胞内代谢途径被激活。然而，杀菌试验显示，粒细胞（细胞与酵母比例为1:1，含10%血清）在孵育3小时期间仅杀死了29%的皮炎芽生菌接种物。综上所述，这些发现表明人类粒细胞对皮炎芽生菌的吞噬作用与细胞内杀伤之间存在差异，这可能是因为这种真菌对粒细胞杀菌机制具有抗性。
