全氟辛烷磺酸(PFOS)经口染毒对C57BL/6小鼠脾脏T细胞亚群CD4+/CD8+的影响

The effect of oral exposure to Perfluorooctane Sulfonate(PFOS) on spleen T cell subsets CD4+/CD8+ of C57BL/6 mice

采用每天一次经口灌胃染毒的方法,探讨了全氟辛烷磺酸(Perfluorooctane sulfonate,PFOS)经口重复剂量染毒对C57BL/6小鼠脾脏T细胞亚群CD4+和CD8+的影响.选择雄性C57BL/6小鼠24只,实验组PFOS染毒剂量分别为5、10、20mg.kg-1(bw).每天一次经口灌胃染毒12d后,制备脾脏T淋巴细胞悬液,经特异性荧光标记的CD3(FITC)、CD4(PE)、CD8(PERCP)单克隆抗体作用后,采用FACS流式细胞仪检测T淋巴细胞及其亚群百分数.结果表明,10 mg.kg-1(bw)和20 mg.kg-1(bw)PFOS染毒组小鼠体重呈明显的下降趋势;20 mg.kg-1(bw)PFOS染毒组小鼠胸腺和脾脏指数显著低于对照组(p<0.05),而各剂量组小鼠肝脏指数均显著高于对照组(p<0.05).PFOS染毒20mg.kg-1(bw)实验组CD3+CD4+与CD3+CD8+T细胞的绝对计数和百分比均显著低于对照组(p<0.01).研究结果显示,PFOS暴露可降低小鼠免疫器官中CD4+、CD8+T细胞的含量,表明PFOS可抑制小鼠的细胞免疫水平.

The objective of this experiment was to assess the effects of Perfluorooctane Sulfonate （PFOS） on spleen T cell subsets through detecting the average positive rate and the numbers of splenic subpopulations of CD4 ＋ and CD8 ＋ T cells. Twenty-four adult C57BL/6 male mice were divided into four groups. Animals were given 0, 5, 10 and 20 mg· kg^-1 PFOS by oral garage every day for 12 days, and then single-cell suspensions of splenocytes were prepared. After labeling with the Flnorescein Isothioeyanate （FITC） conjugated rat-anti-mouse CD3 （monoclonal）, phyeoerythrin （PE） conjugated rat anti-mouse CD4 （monoclonal） and peridinin chlorophyl protein （Percp） conjugated rat anti-mouse CD8 （monoclonal） , the phenotypes of splenocyte populations were analyzed by Flow Cytometry （FCM）. The results showed that in the 12-d study, body weight of mice exposed to 10 mg· kg^-1 and 20 mg· kg^-1 of PFOS showed significant deterioration from their own pre-exposed baseline. Spleen and thymus mass were significantly decreased compared to the control following exposure to 20 mg· kg^-1of PFOS. Furthermore, liver mass was increased in each exposure group. Flow cytometric analysis showed that the average positive rate and the numbers of splenic subpopulations of CIM ＋ and CD8 ＋ ceils decreased significantly in the 20 mg· kg^-1 PFOS group in comparison with normal C57BL/6 mice. This study indicates that PFOS may decrease the average positive rate of CD4 ＋ and CD8 ＋ T-cell in spleen organs, thus suppressing immune function.