血吸虫病快速免疫诊断—胶体染料免疫渗滤法的初步研究

DEVELOPMENT OF A RAPID IMMUNODIAGNOSIS ASSAY FOR SCHISTOSOMIASIS COLLOIDAL DYE IMMUNOFILTRATION ASSAY

目的开发一种适合现场应用的血吸虫病快速免疫诊断方法。方法将纯化的日本血吸虫虫卵可溶性抗原(SEA)点于硝酸纤维素膜上,以捕获血清标本中血吸虫特异性抗体,通过胶体染料R3标记的SEA来直接显色,阳性者出现红色斑点。结果胶体染料免疫渗滤法检测急性血吸虫病人血清35份、慢性血吸虫病人血清107份、晚期血吸虫病人血清35份,其敏感性分别为100％、97.2％和74.3％。检测健康人血清87份,特异性为100％。检测肝吸虫病人血清38份、姜片虫病人血清11份、钩虫病人血清20份,其交叉反应率分别为2.6％、0.0％和0.0％,整过试验过程仅需2～3分钟,操作简单。染料标记SEA在室温条件下保存6个月、37℃恒温中保存62天,其活性均未发生明显变化。结论胶体染料免疫渗滤法检测各期血吸虫病结果准确,操作简便、快速、廉价、肉眼观察结果不需特殊仪器,特别适用于基层现场查病。

Objective To develop a rapid, simple immunodiagnosis assay for schistosomiasis screening in the field. Methods A Colloidal Dye Immunofiltration Assay (CDIFA) was developed by coating the Purified soluble egg antigen of Schistosoma japonicum (SEA) on nitrocellulose membrane, labeling SEA with a red colloidal dye. The whole procedure could be finished within 2 to 3 minutes. Results The sensitivity of CDIFA was 100% in 35 cases of acute schistosomiasis, 97.2% in 107 cases of chronic schistosomiasis, and 74.3% in 35 cases of advanced schistosomiasis. The specificity of the assay was 100% in 87 healthy individuals. The cross reaction was 2.6% in 38 cases of clonorchiasis sinensis and 0.0% in 20 cases of ancylostomiasis and 11 cases of fasciolopsiasis. The antigen dye-labelled was stable at room temperature for at least 6 months, at 37℃ for at least 62 days. Conclusion The Colloidal Dye Immunofiltration Assay provided high sensitivity and good specificity for detection of schistosomiasis and the assay was an inexpensive, simple, rapid, robust test for schistosomiasis screuning without instrumentation suitable for a wide variety of field applications.