title: Hemagglutination activity and colonization factor antigens I and II in enterotoxigenic and non-enterotoxigenic strains of Escherichia coli isolated from humans.
abstract: We examined 205 enterotoxigenic strains of Escherichia coli for colonization factor antigens (CFA) I and II, using an immunodiffusion technique with specific antisera. A total of 36 strains of serogroups O63, O78, O114, O128, and O153 and 1 rough strain possessed CFA/I and gave a single precipitin line; 47 strains of serogroups O6, O8, O80, and O115 possessed CFA/II. The latter strains gave a major precipitin line (component 3) when tested with specific antisera prepared against strain E1392 or PB-176 (both E. coli O6.H16; biotype A). However, all 16 strains of E. coli O6.H16 belonging to biotype A gave a second precipitin line (component 1) when tested with both antisera. When CFA/II-positive strains were tested with a specific antiserum prepared against E. coli O6.H16 strains of biotype B or C, all strains gave component 3, but 16 of 17 strains of E. coli O6.H16 belonging to biotype B, C, or F gave a second precipitin line (component 2) not given by strains of biotype A. CFA/II-positive strains of serogroups other than O6 gave only component 3 in tests with all specific antisera. Nine enterotoxigenic strains of serotypes O7, O15, O25, O115, and O128 gave mannose-resistant hemagglutination of human or calf erythrocytes but lacked CFA/I or CFA/II. Although mannose-resistant hemagglutination was common in non-enterotoxigenic strains of E. coli, none of the non-enterotoxigenic strains possessed CFA/I or CFA/II; these strains included fecal strains of serogroups O6, O8, O63, and O78, fecal strains of enteropathogenic serogroups, and strains from extraintestinal sources.
mesh_terms: D000818:Animals; D000942:Antigens, Bacterial / Q000032:analysis*; D002417:Cattle; D004768:Enterotoxins / Q000096:biosynthesis*; D004926:Escherichia coli / Q000145:classification / Q000276:immunology* / Q000378:metabolism; D036781:Fimbriae Proteins; D006384:Hemagglutination; D006801:Humans; D008358:Mannose / Q000494:pharmacology; D012703:Serotyping
chemical_list: D000942:Antigens, Bacterial; D004768:Enterotoxins; C022924:colonization factor antigens; D036781:Fimbriae Proteins; D008358:Mannose