血吸虫肠相关循环抗原组分CAA和CCA的纯化与特异检测  

PURIFICATION AND SPECIFIC DETECTION OF TWO MAJOR SCHISTOSOMA GUT ASSOCIATED CIRCULATING ANTIGENS, CAA AND CCA *

作　　者：钱宗立[1,2] 王兆军 陆萍[1,2] 

机构地区：[1]上海第二医科大学寄生虫学教研室 [2]荷兰莱登大学寄生虫学研究室

出　　处：《中国寄生虫学与寄生虫病杂志》1999年第2期65-69,共5页Chinese Journal of Parasitology and Parasitic Diseases

基　　金：欧共体INCO-DCSTD-3持续项目基金;中国总理专项研究基金

摘　　要：目的：探讨血吸虫肠相关循环抗原ＣＡＡ与ＣＣＡ诊断靶微粒特异性的差别，并试探获取其纯化制品用于定量检测的标准系列。方法：对两组分进行了亲和层析及阴离子交换剂高效液相纯化分离，并应用单抗检测系统进行同相和异相交互测试。结果：Ｍｏｎｏ－Ｑ－ＨＰＬＣ（高效液相层析）梯度洗脱分离ＡＷＡｊ－ＴＣＡ可溶组分，可获得一个带阳离子活性的非结合ＣＣＡ－１洗脱峰及３个大小不等的、带阳离子活性的ＣＣＡ－２、ＣＣＡ－３及ＣＣＡ－４非结合洗脱峰，以及一个带阴离子活性ＣＡＡ－１洗脱峰。ＣＡＡ活性峰在峰谱上与ＣＣＡ－３有部分重叠。与单抗亲和层析纯品的活性对比测定显示ＣＣＡ－１与ＣＣＡ－２为该组分的主要构成，但ＣＣＡ－２及ＣＡＡ－１在本实验条件下均有微量的相互杂染。同相和异相双位点ＥＬＩＳＡ的４种组合交互检测，展示ＣＣＡ只能在捕获与检测抗体同为抗ＣＣＡ单抗的一种组合中被检出，而另３种组合只能测出ＣＡＡ组分。结论：血吸虫肠相关ＣＣＡ组分为一兼含两性电荷的分子混合体；而ＣＡＡ分子上具有一个可被抗ＣＣＡ单抗识别的活性表位位点，从而可能影响纯化分离和特异检测。AIM: To investigate the specificity differences of the 2 major gut associated diagnostic circulating molecules in Schistosoma japonicum infection, CAA and CCA, and to obtain sufficient purified material for setting up a standard series in quantitative determinations. METHODS: Isolation and purification of the two worm fractions from a trichloroacetic acid (TCA) soluble preparation of S.japonicum adult worm antigen (AWAj TCA) by Mono Q anion exchange chromatography were performed and the specific reactivity of the eluted fractions by antigen capture ELISA (specific for CAA or CCA) with reference to affinity purified preparations of S.mansoni CAA and CCA was analysed. RESULTS: By using an ionic strength gradient, CCA was eluted in two major peaks, an unbound fraction CCA 1, and a major bound fraction CCA 2. Two additional minor peaks, CCA 3 and CCA 4, were eluted at higher ionic strengths. CAA was only detected in a bound fraction, partly overlapping with CCA 3. In the CCA 1 and CCA 2 fractions reactivity was only found in the antigen capture ELISA using anti CCA McAbs both for capture and detection. The CAA fraction was predominantly found to be positive in the antigen capture ELISA using anti CAA McAbs both for capture and detection. However, when using combinations of anti CCA and anti CAA McAbs for capture and detection by ELISA this fraction showed some reactivity. CONCLUSION: Two CCA fractions contain molecules which bear at least two CCA epitopes; while the CAA fraction contains molecules which contain at least two CAA epitopes, and one CCA epitope.

关 键 词：血吸虫 肠相关循环抗原 CAA Mono-Q-HPLC 

分 类 号：R383.24[医药卫生—医学寄生虫学]