摘要
目的观察约氏疟原虫(P·yoelii) 17XL感染DBA/2小鼠的免疫应答机制及免疫效应的动态变化。方法 1×106P·yoelii17XL感染的红细胞经腹腔接种DBA/2小鼠, ELISA测定血清白细胞介素-12 (IL-12)、干扰素-γ( IFN-γ)、IL-4和IL-10的水平以及特异性抗体IgG水平。Griess反应检测脾细胞培养上清中一氧化氮(NO)含量。检测小鼠原虫血症、单核细胞百分率,观测其吞噬疟原虫现象。结果感染小鼠第9天原虫血症高达46·9%,多数小鼠于感染后第20天左右自愈。感染后第6至16天,外周血查见有吞噬作用的单核细胞。感染后第1天起, IL-12水平开始升高; IFN-γ于第6天达最高水平, IL-4和IL-10分别于第9天和第15天达最高水平。脾细胞培养上清NO含量,分别于第6天和第20天显著升高。血清中特异性抗体IgG水平呈增高趋势,至第70天达最高水平。结论 Th1细胞的有效活化对遏制原虫血症和最终清除疟原虫具有重要意义。约氏疟原虫感染早期,单核-巨噬细胞对原虫血症的遏制起到关键作用。
Objective To investigate the development and dynamic changes of host immune response in DBA/2 mice infected with Plasmodium yoelii 17XL. Methods Female DBA/2 mice were infected by intraperitoneal （ i. p. ） injection of 106 P. yoelii 17XL parasitized erythrocytes （ PRBC）. Levels of IL-12, IFN-γ IL-4, IL-10 and P. yoelii 17XL-specific antibody in sera were measured by ELISA. Concentrations of NO in cell supematants were measured by the Griess reaction. Parasitemia, percentage of mononuclear-macrophages of individual mice were monitored daily, and phagncytosis of mononuclear macrophages was also observed. Results Primary parasitemia in vein blood was developed on day 3 postinfection, which peaked with a level of 46. 9% on day 9. Most mice cleared the infection and survived by day 20 postinfection. From day 6 to day 16, the phagocytosis of PRBC by rodent macrophages was observed on the blood smear. Infected mice had a continuously increased level of IL-12 in serum from day 1 postinfection. Accordingly, high level of IFN-γ was also detected in sera from day 1 postinfection, which peaked on day 6. Infected mice produced higher level of IL-4 and IL-10 in serum on day 6 postinfection, which peaked on day 9 and day 15 postinfection respectively. In addition, splenocytes from infected mice produced significantly higher level of NO on day 6 and 20 postinfection. Level of P. yoelii 17XL-specific IgG was determined in the sera of infected mice with a steadily increased trend after infection, which peaked on day 70 postinfection. Conclusions Effective polarizing of Th1 cells is significant in inhibition of parasitemia and eventual clearance of the Plasmodium parasites. Activated play a key role in inhibiting parasitemia in the early phase of infection with P. yoelii 17XL.
出处
《中国寄生虫学与寄生虫病杂志》
CAS
CSCD
北大核心
2006年第1期14-18,共5页
Chinese Journal of Parasitology and Parasitic Diseases
基金
日本"Department of Medicine,Ehime University School of Medicine,Shigenobu,Ehime"资助
