Caused By Weaning Diarrhea And Edema Disease E. Coli F18 Fimbriae Monoclonal Antibody And Its Initial Applications

Abstract:Fl8ab pili of the reference Escberichia coli(E.coli) strain 107/86 from swine with edema disease were purified by a modified procedure. After thermo-separating from the bacterial cells, the pili were concentrated by precipitation with arnmoniurn sulfate, dialyzed, and solubilized in buffer containing deoxycholate. The fraction containing the pili was purified further by ultra-centrifugation in a sucrose gradient. After ultra-centrifugation, the purified pili from strain 107/86 had an molecular weight of l5kD. A panel of four hybridoma cell lines secreting specific antibodies to Fl 8ab pii antigens of E.coli were established from three fusions between mouse myeloma Sp2/0-Ag- 14 and spleen cells from mice immunized with purified Fl 8ab pili antigens The titre of their ascitic fluid was 1:400?1:3200 in direct agglutination(DA). Monoclonal antibodies(MAbs) reacted specifically with FlSab pili from 107/86, while not with Fl8ac pili from 8199, F4-. F5.. F6~ F41 adhesins from enterotoxigenic E.coli(ETEC) and Salmonella Spp in direct agglutination test. Western-blot analysis conformed that 4 McAbs just reacted with 1 5k.D subunit of F 1 8ab pili from strain 107/86, while not with Fl8ac pill from strain 8199. We concluded that the 4 MAbs recognized specifically the 慴?epitope of Fl 8ab pili. The golden particles distributed along the Fl8ab pili irregularly, when strain 107/86 reacted with imrnunogold labeled 4 McAbs.The MAbs have been used in DA to detect F 1 8ab pill antigens of 11 isolates from swines with edema disease. 8 out of 11 were positive,and their 0 serogroups were all 0139. The results suggested that Fl8ab maybe the common pili on E.coli isolated from swine with edema disease.