弓形虫循环抗原诊断试剂的研究

目的　比较弓形虫不同免疫原所制备抗体检测CAg的效果 ,优选高效价的抗体诊断试剂。 方法　制备弓形虫的细胞质抗原 (C)、代谢抗原 (S)。用抗原C、C +S、S及活虫各免疫 2只家兔 ,收集抗血清经纯化而获得IgG抗体 (多抗 )并制备酶标记抗体 ;用上述 4种多抗与多抗 -HRP组合成 16种双抗体夹心型ELISA ,检测人血清CAg和C、S抗原 ,评价试剂的敏感性 ;抗血清与疟原虫、隐孢子虫等抗原进行交叉反应性试验 ,评价试剂的特异性。结果　各种ELISA夹心法同步检测CAg阳性样本 7例 ,阴性样本 8例 ,均未出现假阴性和假阳性反应 ,其OD均值的P/N比值依次为C +C组 33 5、S +S组 2 7 8、CS +CS组 2 1 2、P +P组 13 2 ;C和S抗原的最低检出量均为 0 5 μg/ml;与其它寄生虫未出现交叉反应。 结论　 (1) 4种抗体用于检测人血清CAg、C和S抗原以及其它抗原的结果表明 ,各种抗体试剂均具有良好的敏感性和特异性 ,其中以抗C抗体试剂最为满意。 (2 ) 16种组合形式的夹心ELISA ,检测弓形虫抗原的差异无统计学意义 ,表明弓形虫C和S抗原间存在着共同抗原成分。

Research on circulating antigen diagnostic reagents of Toxoplasma

Aim By comparing the effect that antibody prepared by different Toxoplasma immunogen was used to detect CAg,to select antibody with high titer as diagnostic reagents of Toxoplasma Methods Cytoplasmic (C) and metabolic (S) antigen of Toxoplasma were prepared and two rabbits were respectively immunized with C,C+S,S antigen and live toxoplasma;inorderto to evaluate the sensitivity of reagents,CAg in human sera and C,S antigen were detected by 16 double antibody sandwich ELISA composed of 4 polyclonal antibodies and IgG HRP;Cross reactions of antisera and Malaria,Cryptosporidium antigen were detected Results No false positive and false negative results were found by detecting seven CAg positive and eight CAg negative samples at the same time P/N ratios of medium OD values were 33 5,27 8,21 2 and 13 2 for the group of C+C,S+S,CS+CS and P+P respectively;the least detectable amount of C and S antigen was both 0 5ug/ml;no cross reactions with other parasites was found Conclusion (1) The results of four antibodies detecting CAg in human sera,C,S and other antigens showed that above antibody reagents are all high sensitivity and specificity,especially the anti cytoplasmic antibody (2) No statistic significance has been found in detection of Toxoplasma antigen by 16 composed sandwich ELISA It indicates that common antigenic components might exist between C and S antigen