Cole G T, Seshan K R, Phaneuf M, Lynn K T
Department of Botany, University of Texas, Austin 78713.
Can J Microbiol. 1991 Aug;37(8):637-46. doi: 10.1139/m91-108.
We have demonstrated in a previously described murine model of gastrointestinal (GI) and systemic candidiasis that the antifungal angent cilofungin was efficacious in clearing infection of body organs when administered subcutaneously by infusion, but permitted large numbers of Candida albicans in the GI tract to persist. Yeast and hyphae in these animals were associated primarily with the stratified squamous epithelium of the stomach. Administration of immunocompromising drugs (cyclophosphamide plus cortisone acetate) to animals with persistent GI infection resulted in relapse of systemic candidiasis. Histological examination of the gastric mucosa revealed invasive hyphal elements and yeast as well as multiple chlamydospore-like cells. Comparative histochemical and electron-microscopic examinations of these latter cells produced in host tissue and chlamydospores formed in vitro were conducted. The results suggested that similarities in wall and cytoplasmic composition and ultrastructure exist between these in vivo and in vitro produced C. albicans cells. Exposure of C. albicans to cyclophosphamide during in vitro growth resulted in stimulation of chlamydospore production. No significant effect of cortisone acetate on C. albicans morphogenesis was detected. The murine model used in this study permits investigation of the formation of chlamydospore-like cells of C. albicans during early stages of fungal invasion of cyclophosphamide-treated mice, and of the possible influence of these cells on immunological response of the host to persistent candidiasis of the GI tract.
我们在先前描述的胃肠道（GI）和全身性念珠菌病小鼠模型中已证明，抗真菌药物西洛芬净通过皮下输注给药时，在清除身体器官感染方面是有效的，但胃肠道中仍有大量白色念珠菌持续存在。这些动物体内的酵母和菌丝主要与胃的复层鳞状上皮相关。对患有持续性胃肠道感染的动物施用免疫抑制药物（环磷酰胺加醋酸可的松）会导致全身性念珠菌病复发。胃黏膜的组织学检查显示有侵袭性菌丝成分、酵母以及多个类似厚壁孢子的细胞。对宿主组织中产生的这些后者细胞与体外形成的厚壁孢子进行了比较组织化学和电子显微镜检查。结果表明，这些体内和体外产生的白色念珠菌细胞在细胞壁和细胞质组成以及超微结构方面存在相似性。在体外生长期间，白色念珠菌暴露于环磷酰胺会导致厚壁孢子产生受到刺激。未检测到醋酸可的松对白色念珠菌形态发生有显著影响。本研究中使用的小鼠模型允许研究在环磷酰胺处理的小鼠真菌侵袭早期白色念珠菌类似厚壁孢子细胞的形成，以及这些细胞对宿主针对胃肠道持续性念珠菌病免疫反应的可能影响。
