目的:通过观察2型登革病毒(DEN2)NGC株初次感染和再次感染BALB/c小鼠后小鼠血浆中TH1和TH2类细胞因子的产生及其动态变化,研究DEN2感染的免疫机制。方法:用不同量的DEN2NGC株经皮下多点注射,建立BALB/c小鼠感染模型,间接ELISA法测定感染后不同时间小鼠血浆IL-2、IFN-γ、IL-4、IL-5、IL-6、IL-10的含量。结果:(1)在初、再次感染阶段,DEN2 NGC株各感染组产生IL-4、IFN-γ、IL-2、IL-5、IL-6、IL-10与正常对照组有显著差异(P〈0.05)。①在初次感染阶段,NGC株各感染组血浆IL-2、IL-5、IL-6于第4、6、8天出现;在再次感染阶段,各感染组产生IL-2、IL-5、IL-6均于第1天迅速升高;IL-2水平于第4天达高峰(104448.46±13314.1pg/ml),维持5—7天后迅速下降;IL-5于48小时达到高峰(135.125±46.75pg/ml);各组小鼠IL-6产生的动态相似,在再次感染后第1天,达高峰(555.823±44.639pg/ml)后逐渐下降。②初次感染早期,IL-4水平明显升高,而IFN-γ处于较低水平;再次感染后第1天,IL-4水平达最高峰(4294.668±349.038pg/ml),IFN-γ则于第4天和第11天达较高水平,两者的产生彼消此长,且产生动态与感染病毒量有关。(2)在初、再次感染阶段,用不同量DEN2 NGC株感染组产生细胞因子水平有差异。结论:DEN2 NGC株初次和再次感染BALB/c小鼠后,TH1和TH2应答均可发挥一定作用,二者相互影响,TH细胞及其产生的CK在DEN感染的发病机制中起重要作用。
Objective: To observe the dynamic levels of TH1/TH2 eytokines from the plasma of BALB/c mice infected with DEN2 NGC strain and research immune response mechanism. Methods: The BALB/e mice plasma samples collected from different experiment groups at various time after infection were tested for IL-2 ,IFN-γ,IL-4 ,IL-5, IL-6 and IL-10 levels with indirect ELISA. Results:( 1 )The BALB/c mice could produce IL-2, IFN-γ, IL-4, IL-5, IL-6 and IL-10 after DEN2 infection and the correlation of eyto- kines with normal group(P 〈0. 05). ①The eytokines that appeared were IL-2 on the fourth day,IL-5 on the sixth day,and IL-6 on the eighth day after DEN2 infection;In the reinfection phase,IL-2 appeared on the first day with a rapid peak on the fourth day( 104 448.46 ± 13 314. 1 pg/ml) and then declined quickly after 5 to 6 days;IL-5 appeared on the first day and reached a peak( 135.. 125 ±46. 75 pg/ml) ;IL-6 appeared on the first day with a peak on the 48 h(55. 823 ±44. 639 pg/ml). ②Tbe dynamic levels of IL-4 and IFN-γ/in the plasma of BALB/c mice infected with DEN2 NGC strain were different. The levels of IL-4 were significantly increasing after DEN2 infection while that of IFN-γ/were lower:IL-4 reached a peak on the first day(4 294. 668 ± 349. 038 pg/ml) and then the levels of IFN- γ/higher on the forth and eleventh day. (2)The concentrations of eytokines produced by infected animals had been.closely associated with the doses of DEN2. Conclusion:Both Thl and Th2 responses are induced by DEN2 and play a role;while,Th2 response is more predominant than Thl response. Th cell and Th-related cytokines are importance with DEN infective diseases.