Establishment and Preliminary Application of Double-McAb Sandwich ELISA for Detection and Analysis of S.typhi O,H,and ViAntigens
Wei Bo;Peng Jing;Zhou Theliang(Lanzhou institute of Biological Products, 730046)
Totally thirty murine hybridoma McAbs reactive with 09,012, Hd and Vi antigens ofS.typhi were obtained from Cell fusion by immunolising BALB/c mice with whole cellsof S.typhi.Several McAbs to different antigens were selected on the basis of detection ofimmunoglobulin subelass, antibody titer of and epitope. Double antibody sandwich ELISA was developed using IgG-class McAb as capture or probe antibody to detect O, H, and Vi antigens ofS. typhi.The sensitivities of detection for soluable S.typhi liPOPOlysaccharide(O antigen),flagellin (Hantigen), and Vi were 15.625 ng /ml,sng/ml and 0.305ng/ ma respectively.The ldriit of detectionfor whole bacteria was 105～106 cells/ml.By use of the assay O,H,and Vi antigens were detectedin 27 of the 104 hemoculture samples from patients.Positive samples were confirmed to be infectedwith S.typhi by bacteria isolation.The results indicate that the assay has high sensitivity andspecificity.The assays for detection and analysis of antigen comPOnents might be applied to the early,rapid diagnosis of typhoid fever.