恶性疟原虫体外抑制实验方法的改进

以恶性疟原虫融合抗原PfCP-2.9免疫兔血清为待测血清,将起始原虫率从1%降至0.2%～0.5%,采用2种方法作对比,即一组每24 h更换培养液、加入免疫血清,另一组72 h内不更换培养液也不加免疫血清试验方法.培养至72 h,涂片,油镜下计数,计算原虫感染率和抑制率.结果2组的抑制率相近,经统计分析无显著差异.测定不同剂量抗原免疫血清的抑制率,结果显示抑制率与免疫血清中特异抗体滴度呈正相关,2种方法的结果无显著差异.研究表明通过降低起始原虫率可将常规体外抑制实验由需每天换液改为72 h不换液.

Modification of inhibition assay for Plasmodium falciparum in vitro

This paper is to modify growth inhibition assay for Plasmodi um falciparum in vitro . Sera of rabbits immunized with P. falciparum chime ric protein PfCP 2.9 were detected for inhibition of parasite growth using 2 me thods: refreshing culture medium at 24 h interval and 72 h interval. The init ial parasitemia for the 2 methods was decreased from 1% to 0.2% 0.5%. After 72 h of cultivation, thin blood films were prepared to count parasites within 3 00 0 RBC. The inhibition rates obtained from 2 methods were not significantly different( P >0.05). A panel of immune sera with various doses of specific a ntibodies were detected by the modified method and the inhibition was positively correlated to antibody level of the sera, and no significant differen ce of inhibition rates ( P >0.05) were found between 2 method s. A modified in vitro inhibi tion assay without refreshing medium during a period of 72 h is established by r eduction of initial parasitemia from 1% to 0.2% 0.5%.