主动入侵的疟原虫子孢子通过CSP蛋白诱导DC成熟

目的观察约氏疟原虫子孢子能否诱导DC成熟,并探讨其机制。方法GM-CSF常规诱导小鼠骨髓前体细胞,获得足量的DC,然后,解剖按蚊唾液腺子孢子与DC共培养,分别于2、4和24 h后,荧光显微镜下观察子孢子与DC的相互关系,同时采用流式细胞分析技术检测DC表面的MHC-Ⅱ类分子、CD80和CD86共刺激分子的表达情况,最后转染重组pFLAG-CMV8-CSP质粒后24 h,检测DC表面的共刺激分子的表达情况。结果在共培养后2h,子孢子便逐渐向DC迁移甚至黏附于DC表面;4 h后部分子孢子便进入DC且仍然保持子孢子的弯月形形态;24 h后DC内的部分子孢子逐渐变圆,类似肝期裂殖体的形态。流式检测发现共培养2 h后对DC共刺激分子表达无明显影响,而共培养4 h和24 h后DC共刺激分子的表达均上调。转染pFLAG-CMV8-CSP重组质粒至DC中后同样能诱导DC的共刺激分子的表达上调。结论在体外共培养的情况下,大部分子孢子可以主动侵入DC而少部分可以被DC吞噬,主动入侵DC的子孢子可能是通过其表面的CSP由纳虫空泡进入胞浆内后诱导DC成熟。

Actively invaded Plasmodium yoelii sporozoites induce DC maturation via circumsporozoite protein in vitro

In this paper,we observe the interaction of Plasmodium yaelii sporozoites with bone marrow-dendritic cells,and investigate whether sporozoites could induce DC maturation.Dendritic cells(DCs) were induced by GM-CSF from mouse bone marrow in vitro,and co-cultured with sporozoites dissected from Plasmodium yoelii-infected Anopheles stephensi.Different time later,the interaction betwoen the DCs and sporozoites were observed under fluorescence microscope:at 2 h,sporozoites were found to be adhered on DCs;at 4 h,...