阴道上皮细胞、白假丝酵母菌及卷曲乳杆菌相互作用的扫描电镜观察

Scanning electron microscopic observation of interactions of vaginal epithelial cells with Candida albicans and Lactobacillus crispatus

目的探讨阴道上皮细胞（VEC）与白假丝酵母菌相互作用的机制以及卷曲乳杆菌对VEC的保护作用。方法培养阴道上皮细胞系VK2／E6E7细胞并分别制备白假丝酵母菌及卷曲乳杆菌悬液，应用扫描电镜观察VEC与白假丝酵母菌共同培养及加入卷曲乳杆菌干预后的超微结构变化。结果白假丝酵母菌感染VEC6h时，其侵袭VEC以诱导内噬方式为主，VEC表面伪足增多，接触并覆盖于白假丝酵母菌假菌丝表面；自假丝酵母菌感染12h时，其侵袭VEC以主动穿透方式为主，白假丝酵母菌穿透VEC，破坏其表面结构，VEC伪足减少、消失，细胞膜破坏甚至导致细胞死亡。加入卷曲乳杆菌干预后，VEC的形态有所恢复，白假丝酵母菌假菌丝结构破坏。结论白假丝酵母菌通过诱导内噬作用及主动穿透作用侵袭VEC；在白假丝酵母菌感染过程中，卷曲乳杆菌可通过占位效应对VEC发挥一定的保护作用。

Objective To investigate interactions of vaginal epithelial cells （VEC） with Candida albicans and the protective effect of Lactobacillus crispatus on VEC. Methods VK2/E6E7 VEC cell line was cultured. Candida albicans and Lactobacillus crispatus suspension were prepared respectively. Uhrastructural morphological changes of VEC infected with Candida albicans and treated with Lactobacillus crispatus were observed by scanning electron microscope （SEM）. Results Candida albicans invaded into VEC mainly through endocytosis after an early infection of 6 hours. Pseudopods of VEC increased, contacted and covered the surface of pseudohyphae. After 12 hours infection, active penetration developed into the predominant invasion mechanism. Candida albicans directly penetrated through VEC, destroyed the surface structures, and even led to cell death. A reduction of pseudopods on VEC was observed. After co-incubation with Lactobacillus crispatus, SEM revealed a morphological recovery of VEC and destruction of pseudohyphae. Conclusions Candida albicans invade VEC mainly through endocytosis and active penetration. Lactobacillus crispatus could utilize occupying effect to exert protective effect on VEC during the infection with Candida albicans.