【摘要】 目的探讨免疫抑制剂FK506(他克莫司,Tacrolimus)对弓形虫急性感染后小鼠干扰素γ(IFN-γ)和白介素2(IL-2)的活性以及对肝虫负荷的影响。方法用102个RH株弓形虫速殖子腹腔接种昆明小鼠120只,然后随机分为FK506组〔A组,每d用FK506 1mg/(kg.d)灌胃〕和对照组(B组,每d用等量生理盐水灌胃),每组60只,雌雄各半;分别于感染后第2、4、6、7、9 d随机取8只小鼠外周血,用ELISA法测定血清IFN-γ和IL-2的活性,同时取肝脏用荧光定量PCR法检测肝脏的虫荷。另外检测8只健康小鼠的IFN-γ和IL-2数值,作为正常值。结果A组小鼠于感染后第8d全部死亡,B组小鼠于感染后第10d全部死亡。感染后第2、4、6、7 d A组小鼠血清IFN-γ活性明显低于B组(P<0.05或P<0.01)。IL-2活性除感染后第2d两组在统计学上无显著性差异外,从感染后第4 d开始,A组的IL-2水平显著低于B组,而且差别越来越显著(P<0.05或P<0.01)。在感染后第4和第7 d A组的肝平均虫荷显著高于B组(P<0.01)。结论FK506对T淋巴细胞免疫有显著的抑制作用,导致机体的免疫力下降,加剧弓形虫的感染。更多还原

【Abstract】 To evaluate the effect of FK506 on kinetic activity of IFN-γ and IL-2 in serum,and parasite load in liver in mice infected with Toxoplasma gondii(T.gondii).One hundred and twenty mice were infected with T.gondii by intraperitoneal injection of 10~2 tachyzoites.Then the mice were assigned randomly into 2 groups.FK506(1mg/(kg.d)) was given to mice in group A orally and normal solution was given to mice in group B.At 2, 4,6,7 and 9 days after infection,8 mice were killed each time to collect the blood sera and livers respectively.The activities of IFN-γ and IL-2 in serum were assayed by biological method and parasites loads in livers were determined with quantitative fluorescence polymerase chain reaction(PCR).The normal value of IFN-γ and IL-2 was acquired from another 8 healthy mice.It was found that the mice died on day 8 after infection in group A and on day 10 in group B.The activity of IFN-γ in group A on day 2,4,6,7 after infection was significantly lower than that in group B(P <0.05 or P <0.01),the activity of IL-2 on day 4,6,7 after infection in group A was significantly lower than that in group B(P <0.05 or P <0.01) except that on day 2 after infection,the parasites loads in livers at 4d and 7d after infection in group A were significantly higher than that in group B(P <0.01).In conclusion,the protective immunity after acute T.gondii infection can be inhibited by FK506 and as a result,mass parasites reproduced and led to earlier death of hosts.更多还原