IL-2、IFN-γ在弓形虫感染小鼠脾细胞的活性动态

The Kinetics of IFN-γ、IL-2 in Mice Infected By RH Strain Toxoplasma Gondii

目的 研究小鼠感染RH株弓形虫后脾细胞的IFN -γ、IL - 2活性动态变化。方法 用 2× 10 3 个RH株弓形虫速殖子腹腔接种昆明小鼠 ,分别在感染前、感染后直至小鼠死亡每天随机取 5只鼠脾脏 ,用生物学检测法测定感染前、感染后鼠脾细胞IFN -γ、IL - 2的活性 ,结果用F检验进行统计学分析。结果 感染后第 2d、第 5d、第 7d小鼠脾细胞IFN -γ活性虽有升高 ,但各组均值与感染前比较均无显著性升高 (P >0 0 5 ) ,感染与未感染小鼠的IFN -γ活性无显著性改变 (P >0 0 5 )。鼠脾细胞IL - 2活性在感染前、后有显著性变化 (P <0 0 5 )。感染后第 3d、4d较第 2d、第 5d、第 7d显著性下降 (P <0 0 5 ) ,至感染后第 9d感染鼠全部死亡。结论 RH株弓形虫感染宿主后剌激宿主产生的内源性IFN -γ和高活性的IL - 2不能引起有效的保护性免疫 ,致使虫体大量繁殖 ,小鼠死亡。

Aim To study the kinetics of activity of IFN γ and IL 2 produced by splenocytes from mice infected withToxoplasma gondii RH tachyzoites.Methods Each Kunming mouse was intraperioneally injected with 2×10 3 T.gondii RH tachyzoites.Five mice were killed randomly and obtained splenocytes daily at preinfection and postinfection respectively.The activity of IFN γ and IL 2 produced by splenocytes was assayed by biological method.Results The activity of IFN γ had elevated on day 2,5,7 postinfection(PI),but not significantly increased compared with that of preinfection(P>0 05).The activity of IL 2 PI has significantly increased compared with that of preinfection(P<0.05).The activity of IL 2 on day 3,4 PI was significantly decreased compared with that on day 2,5,7 PI(P<0.05).The infected mice died on day 9 PI.Conclusion The endogenous IFN γ and high activity IL 2 produced by splenocytes of infected mice can not produce protective immunity effectively.As a result,mass parasites reproduced and led to the death of hosts.It is necessary to study the mechanism of suppressive immunity in infected mice.