三种条件致病性真菌组织型凝集素结合形式的实验研究

A study on lectin binding patterns of 3 opportunistic fungi in tissues of experimentally infected mouse

用生物素标记凝集素—卵白素过氧化酶法研究了白念珠菌、热带念珠菌及新生隐球菌在实验性小鼠感染病变中组织型的14种凝集素结合形式,并与其室温下培养的菌细胞结合形式比较。结果白念珠菌培养细胞与刀豆凝集素(ConA),扁豆凝集素(LCA),及豌豆凝集素(PSA)反应阳性,其他11种凝集素阴性。组织型茵细胞除与琥珀酸麦胚凝集素(SWGA)反应阳性外,其他结合形式同培养菌细胞,提示培养菌细胞转为组织型细胞壁糖分发生变化。热带念珠菌结合形式同白念珠茵,说明同属真菌细胞壁糖成分和结构的相似性。新生隐球菌与14种凝集素均不结合,与念珠菌结合形式不同,提示利用凝集素鉴定组织内病原真菌的可能前景。

The lectin binding patterns of 3 opportunistic fungi—Candida albicans, Gandida tropicalis and Cryptococcus neoformans both lin culture—form (on the Sabourauds agar at room temperature) and tissue—form (in the affected tissue of experimentally infected mouse),were studied using 14 different biotinyl lectins and avidin-horseradish peroxidase.Candida albicans in culture-form was stained with Con A,LCA,and PSA while not stained with BSL,DBA,PHA-E,PHA-L,PNA,RGA,SBA,SJA, UEA,WGA and sWGA.The tissue form of Candida albicans was stained with ConA,LCA,PSA,BSL,DBA,PHA-E,PHA-L,PNA,RCA,SBA, SJA,UEA,and WGA identically with its culture-form.However,a positive staining with sWGA was observed in the tissue-form,suggesting that certain changes in the carbohydrate component occur in the cell wall of Candida albicans in relation to the conversion of culture-form to tissue-form.The binding patterns with all lectins studied to Candida tropicalis both in culture-form and tissue-form,were identical respe- ctively with those to candida albicans.The results demonstrate the similarity of Carbohytrate components and structure in the fungal cell wall between these two species of fungus in the same genus.Both culture- form and tissue-form of Cryptococcus neoformans were not stained with all lectins studied.The different lectin binding patterns hetween Gandida and Cryptococcus provide a probably useful method to detect and identify fungal pathogens in tissue seetions by lectin histochemistry