妊娠早期感染犬弓首线虫对仔鼠免疫状态的影响

Study on Infection of Female Mice with Toxocara Canis to Immune State for Offsprings in Early Pregnancy

目的研究母体妊娠早期感染犬弓首线虫,是否影响仔鼠的体液免疫功能。方法取犬弓首线虫子宫段虫卵培养至感染期,不同剂量(生理盐水、1×10~3个、3×10~3个虫卵)感染受孕三天的雌鼠,待仔鼠6周龄时攻击感染(0.5×10~3个虫卵、生理盐水),实验共分6组,动态检测各组仔鼠血清细胞因子(IL-2,IL-4,IL-10,IFN-γ)的表达。结果各组仔鼠血清细胞因子有差异,具有统计学意义(P<0.05);各细胞因子之间变化规律不同:Th1细胞产生的细胞因子IL-2在攻击感染早期呈上升趋势,4周达到高峰,以后逐渐下降;IFN-γ在攻击感染早期呈上升趋势,第2周达到高峰后逐渐下降。Th2细胞产生的细胞因子IL-4和IL-10攻击后呈下降趋势,且下降趋势在早期下降明显,后期逐渐放缓。结论妊娠早期感染孕鼠会影响仔鼠的体液免疫调节能力,且可诱导仔鼠对后天感染产生明显保护性免疫记忆;仔鼠的获得性免疫,在攻击感染的早期可能以Th2免疫占优势。

Objective To investigate whether infection with Toxocara canis in early pregnancy affect humoral immunity of offspring. Methods Took several groups of three-day pregnant female mice infected with different do- ses of Toxocara canis eggs （normal saline, 1 x 103 eggs, 3×10^3 eggs）. When the offsprings were 6-week-old, they were divided into six groups, and aggressively infected with Toxocara canis eggs （normal saline, 0.5 ×10^3 eggs）. Serum cytokines（IL-2,IL-4,IL-10,IFN-γ）were measured by ELISA. Results Serum cytokines of offspring were significantly different in each of the groups （P 〈 0.05 ）. The variations among different serum cytokines appeared various patterns. IL-2 cytokine was produced from Thl cells, showed an ascending trend at the early period of ag- gressive infection and attended the peak on four weeks, then descended gradually. IFN-~/ also showed the ascend- ing trend at the early period, and attended the peak on two weeks, then descended gradually. IL-4 and IL-10 cyto- kines were produced from Th-2 cells, which presented a descending trend after an aggressive infection along with significantly descending trend at early period, and then slow clown in the later period. Conclusions The infection with Toxocara canis eggs during pregnancy period may affect offspring＇s immune regulation. When the offspring were infected once again, they would produce protective immune memory. The acquired immune serum was possibly pro- duced from the dominant position of Th-2 cells on the early period of aggressive infection.