Merkel G J, Scofield B A
Department of Microbiology and Immunology, Indiana University School of Medicine, Ft. Wayne 46805.
J Med Vet Mycol. 1993;31(1):55-64.
Conditions affecting the adherence of clinical isolates of Cryptococcus neoformans to rat glial and lung cell cultures were studied. Adherence to glial cells was a time-dependent process that was affected by the yeast culture age and growth temperature. The most adherent yeasts were those from 48 h cultures grown at 37 degrees C. Formalin-treating the yeasts did not affect adherence but formalin-treating the glial monolayers prevented yeast binding. Treating the yeasts with trypsin reduced adherence to glial monolayers, indicating that the yeast adhesin had a trypsin-labile protein component. Certain carbohydrates inhibited cryptococcal adherence to glial and lung cells in a time and concentration-dependent manner. Of the carbohydrates tested, N-acetyl-D-glucosamine, sucrose, lactose, sorbitol and myo-inositol were the most inhibitory, while mannose, galactose and xylose were the least inhibitory. The results collectively indicated that the mechanisms of adherence of C. neoformans to lung cells were similar to those of glial cells and that both involved a protein-containing adhesin on the cryptococcal surface that was expressed only after growth at 37 degrees C. Carbohydrate receptors also appeared to be involved with these interactions.
研究了影响新型隐球菌临床分离株对大鼠神经胶质细胞和肺细胞培养物黏附的条件。对神经胶质细胞的黏附是一个时间依赖性过程，受酵母培养物的培养时间和生长温度影响。黏附性最强的酵母是那些在37℃培养48小时的培养物中的酵母。用福尔马林处理酵母不会影响黏附，但用福尔马林处理神经胶质细胞单层会阻止酵母结合。用胰蛋白酶处理酵母会降低其对神经胶质细胞单层的黏附，这表明酵母黏附素具有对胰蛋白酶敏感的蛋白质成分。某些碳水化合物以时间和浓度依赖性方式抑制隐球菌对神经胶质细胞和肺细胞的黏附。在所测试的碳水化合物中，N-乙酰-D-葡萄糖胺、蔗糖、乳糖、山梨醇和肌醇的抑制作用最强，而甘露糖、半乳糖和木糖的抑制作用最弱。这些结果共同表明，新型隐球菌对肺细胞的黏附机制与对神经胶质细胞的黏附机制相似，且两者都涉及隐球菌表面一种仅在37℃生长后才表达的含蛋白质的黏附素。碳水化合物受体似乎也参与了这些相互作用。
