Apoptosis within mouse eye induced by Toxoplasma gondii

弓形体诱发的小鼠眼内细胞凋亡(英文)

Objective To investigate apoptosis induced by Toxoplasma gondii (T. gondii) in eyes of C57BL/6 (B6) mice. Methods Apoptosis was detected by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end labeling (TUNEL) technique and pathological changes within eyes were analyzed at different time points after intraocular inoculation of either 50 or 500 of tachyzoites. Results In eyes that received 50 tachyzoites, a few apoptotic inflammatory cells in the anterior chamber and keratocytes in the cornea were seen at days 1 and 2, but no apoptosis was detected 4 days after inoculation. Significantly greater apoptosis of inflammatory cells was observed in the anterior chamber and in the vitreous of eyes injected with 500 parasites. Apoptosis of inflammatory cells in the anterior chamber and of keratocytes in the cornea was seen at day 1. The apoptotic stromal keratocytes strikingly increased at day 4. There were a number of apoptotic inflammatory cells in the vitreous at day 2, and a few apoptotic retinal cells along the internal limiting membrane and the nerve fiber layer of the retina 4 days after inoculation. Conclusion These results suggest that apoptosis of inflammatory cells infiltrated eye infected with this parasite may be a mechanism of eliminating the organism.

目的 探讨弓形体在C57BL/6(B6)小鼠眼内诱发的细胞凋亡。方法 凋亡的检测是通过末端脱氧核苷转移酶介导的脱氧尿核苷三磷酸生物素缺口末端标记 (TUNEL)技术 ,我们同时对眼内接种 50或 50 0个速殖子后不同时间点的病理变化进行了分析。结果 在接种 50个速殖子的小鼠眼内 ,接种后 1到 2天 ,可见到前房内少量炎症细胞和角膜细胞的凋亡 ,但接种后第 4天则未检测到细胞凋亡。而在注射了 50 0个寄生虫的小鼠眼内 ,前房和玻璃体内均可见到显著增多的炎症细胞凋亡 ,第 1天即可见到前房内炎症细胞和角膜内基质细胞的凋亡 ,且凋亡的基质角膜细胞在第 4天明显地增多。第 2天在玻璃体出现一定数量的凋亡炎症细胞。第 4天沿视网膜内界膜及神经纤维层可见少量凋亡视网膜细胞。结论 以上结果提示 ,弓形体感染的眼内浸润炎症细胞的凋亡可能是杀灭这种寄生虫的机制之一。但是大量的炎症细胞凋亡在眼弓形体病中也可能造成对眼组织的损害。