leukotoxin and Haemophilus-Infections

Haemophilus paragallinarum is the causal agent of infectious coryza, an economically important disease for the poultry industry. This bacterium secreted proteins of 25-110 kDa during its growth in brain heart infusion, tryptic soy broth, or Luria-Bertani glucose phosphate media, all lacking serum. Some of these proteins were recognized by sera from chickens experimentally infected with H. paragallinarum. A 110-kDa protein was recognized by a serum pool from convalescent-phase pigs naturally infected with Actinobacillus pleuropneumoniae, and also by a rabbit polyclonal serum against Apx I as well as a rabbit serum against Mannheimia haemolytica leukotoxin, suggesting the presence of an RTX-like protein in H. paragallinarum. H. paragallinarum secreted proteins could be important immunogens in the control of infectious coryza.

Topics: Actinobacillus Infections; Actinobacillus pleuropneumoniae; Animals; Antibodies, Bacterial; Antigens, Bacterial; Bacterial Proteins; Blotting, Western; Chickens; Cross Reactions; Culture Media; Exotoxins; Haemophilus Infections; Haemophilus paragallinarum; Mannheimia haemolytica; Molecular Weight; Pasteurellaceae Infections; Poultry Diseases; Rabbits; Swine; Swine Diseases