检测囊虫循环抗原胶体金试条的研制与初步应用

Development and primary application of gold immunochromatographic assay trips for detecting the circulating antigen of Taenia solium cysticercosis

目的研制快速检测囊虫循环抗原(CA)的胶体金试纸法。方法以部分纯化囊虫抗原免疫BALB/c小鼠制备抗CA单克隆抗体(McAb),经筛选获得5株能稳定分泌McAb的杂交瘤细胞株。用制备的McAb两两配对,制备了囊虫CA免疫胶体金快速诊断试条。结果以1A5和1B6配对的试条对人体囊虫CA、囊虫CA标准抗原以及63份囊虫病患者血清、9份脑囊虫病患者脑脊液的检测结果均为阳性,对弓形虫病感染者、包虫病患者及非疫区献血员血清的检测结果均为阴性;与酶联免疫吸附试验(ELISA)的平行对比试验表明,试条检测敏感性与ELISA的敏感符合率为97.03%。结论研制的免疫胶体金诊断试条可用于人体囊虫病CA的特异性诊断和流行病学调查。

Objective To develop a new simple and rapid method to detect the circulating antigen （CA） of Taenia solium cysticercosis. Methods Five hybridoma strains which secret monoclonal antibodies （McAbs） against CA were established and used for screening the optimal composition of gold immunochromatographic （GICA） trips. Two McAbs were purified and applied for preparation GICA trips by labeling one McAb with colloidal gold and coating another on nitrocellulose membrane. The sensitivity and specificity of GICA were evaluated by comparison with sandwich ELISA. Results The optimal composition was McAbs 1 A5 and 1136. The optimal amount of McAb 1 A5 marked with 1 ml colloidal gold was 10 μg/ml, and the optimal coating concentration of McAb 1 B6 was 1 mg/ml. Concordance between GICA and the ELISA for detecting the CA in sera of sick pigs, the sera and cerebrospinal fluid of patients, and cyst fluid was 97.03%. No positive results were detected in the negative control sera. Threshold value of GICA was 10 ng of CA, and the detection time was about 5 minutes. The GICA strips that were stored at 4℃ and at room temperature for 105 days or at 37℃ for 45 days had same performance in the detection. Conclusions The GICA method may efficiently detect CA of Taenia solium cysticereosis, and is suitable for field surveillance of Taenia solium cysticercosis.