摘要
目的 观察白细胞介素 12 (IL - 12 )对伯氏疟原虫 (P.b)红内期感染小鼠 Th1/ Th2细胞因子表达水平的影响 ,探讨 IL- 12介导 Th1/ Th2免疫偏移在抗 P.b红内期感染中的免疫调节作用。方法 BAL B/ c小鼠接种 5× 10 5个感染 P.b的红细胞 ,同时分别给予 0 .0 3μg/ d或 0 .15 μg/ d IL- 12处理 ,用 EL ISA方法检测 P.b感染小鼠血清或脾淋巴细胞体外培养上清中细胞因子 IFN-γ、IL - 4表达水平的动态变化。结果 0 .0 3μg/ d IL - 12处理组小鼠接种感染后第 7天取脾淋巴细胞体外经PHA或可溶性抗原 s Ag刺激培养产生的 IFN- γ水平较感染对照组显著升高 ,IL- 4水平显著下降 ,而 0 .15 μg/ d IL- 12处理组脾淋巴细胞产生的 IFN- γ及 IL- 4水平均较感染对照组显著下降。在感染后第 3天 ,0 .0 3μg/ d或 0 .15μg/ d IL - 12处理组小鼠血清中 IFN-γ均已出现 ,第 5天达高峰 ,但感染后第 7天 0 .15 μg/ d IL- 12处理组血清中 IFN- γ迅速下降 ,甚至低于感染对照组及 0 .0 3μg/ d IL- 12处理组 ,感染对照组直到感染后第 7天血清中方可检测到 IFN- γ水平。结论 适当低剂量 IL- 12诱导 CD4 + Th1免疫应答 ,产生细胞因子 IFN-γ,以诱导抗 P.b红内期感染的免疫保护作用 ;而较大剂量 IL - 12抑制机体抗感染?
Objective To study the effect of IL-12 on Th1/Th2 cytokine expression level and the role of IL-12 in the shi ft ing of Th1/Th2 immune response against blood-stage Plasmodium b e ighei infection in mice. Methods [WT5”BZ ]BALB/c mice were infected with 5×105 parasitized RBC and received doses of 0.03 or 0.15 μg/d of IL-12 on the day of infection and daily for 6 days post -in fection. The levels of IFN-γ and IL-4 in sera or supernatants of splenic lymp hocyte cultured in vitro were detected by the EL ISA method. Results Compared with spleen cells fro m untreated mice, spleen cells from 0.03 μg dose of IL-12-treated mice produ ced significantly higher level of Th1-associated cytokine IFN -γ, but lower level of Th2-associated cytokine IL-4 in response to PHA or sA g stimulation on day 7 post-infection, whereas spleen cells from 0.15 μg dose I L-1 2-treated mice produced significantly lower levels of IFN-γ and IL-4. The le vel of IFN-γ was apparent in the sera of mice treated with 0.03 or 0.15 μg/d I L-12 on day 3 post-infection and peaked on the day 5 post-infection, but level of I FN-γ even was significantly lower in mice treated with 0.15 μg/d IL-12 comp ara ble to that in control mice on day 7 post-infection. The level of IFN-γ was n ot detected in the sera of control mice through 7 days post-infection. [WT5” H Z] Conclusion Appropriate dose of IL-12 regulates the deve lop ment of resistance to P.berghei via a CD 4+ T h1 response, which involves the cytokines IFN-γ. [HT5”SS] However, higher doses of IL-12 dramatically inhibite immune pro t ective ability, which may be detrimental to resistance against P .berghei infection. [
出处
《中国血吸虫病防治杂志》
CAS
CSCD
2004年第5期363-366,共4页
Chinese Journal of Schistosomiasis Control
基金
江苏省自然科学基金资助项目 ( NO.BK9715 7)
