抗大肠杆菌耐热性肠毒素ST1 McAb杂交瘤细胞系的建立及应用

Establishment and application of hybridoma cell lines secreting monoclonal antibodies against enterotoxigenic Escherichia coli heat-stable enterotoxinⅠ

目的耐热性肠毒素ST1单克隆抗体制备及在感染性腹泻诊断中的应用。方法应用基因工程菌株分泌的肠毒素制备ST1包涵体,免疫Balb/c小鼠,成功制备了3株特异性抗ST1的单克隆抗体细胞株,用其中1株McAb建立了检测ST1的双单克隆抗体夹心ELISA法。结果检测52株从临床腹泻病人粪便中分离的大肠杆菌,检出ST1阳性率为26.92%,与ST1检测的经典方法乳鼠灌胃法符合率为96.15%。结论该方法是一种简捷、灵敏和特异的检测方法,具有实际应用价值。

Objective To prepare monoclonal antibody （McAb） against heat-stable enterotoxin （ST1） and study its clinical application in infectious diarrhea. Methods The ST1 inclusion body was prepared using the entemtoxin secreted from genetically engineered strain, and then mixed with Freund＇s complete adjuvant to immune Balb/c mice. Splenocyte and myeloma cell Sp2/0 lines were fused. Three hybridoma cell lines secreting specific McAbs against ST1 antigen were attained. One McAb sandwich ELISA was established for determination of ST1. Results ST1 was detected in 52 E. coli strains separated from the faeces of patients with infectious diarrhea （positive rate was 26.92% ）. The positive coincidence rate of ELISA assay with the typical suckling mouse assay has reached 96.15 %. Conclusion Establishment of a sandwich ELISA provides a fast, simple, sensitive, and specific method for the diagnosis of ETEC ST1 in clinical practices.