title: Sex pili as immunogens.
abstract: Groups of chickens were vaccinated intravenously with live cultures of Escherichia coli K12 possessing transfer factors F, I, A2 or no transfer factor (Tra-minus) and their immunity challenged by injecting them intravenously with an F-plus strain of Salmonella heidelberg or an F-plus or I-plus strain of Salmonella typhimurium. Compared with the Tra-minus strain, vaccination with the F-plus, but not the I-plus or A2-plus, K12 strain significantly reduced the mortality rate caused by the F-plus salmonella strains; vaccination with the I-plus or A2-plus, but not the F-plus, K12 strain significantly reduced the mortality rate caused by the I-plus salmonella strain.
mesh_terms: D000372:Agglutination Tests; D000818:Animals; D000942:Antigens, Bacterial; D002645:Chickens; D003227:Conjugation, Genetic; D004926:Escherichia coli / Q000276:immunology* / Q000648:ultrastructure; D005144:F Factor; D007118:Immunoassay; D009026:Mortality; D012475:Salmonella / Q000276:immunology* / Q000648:ultrastructure; D012480:Salmonella Infections / Q000276:immunology; D012486:Salmonella typhimurium / Q000276:immunology / Q000648:ultrastructure
chemical_list: D000942:Antigens, Bacterial