Characterization and chemical nature of Haemophilus avium hemagglutinin.

Haemophilus avium hemagglutinin properties were studied. Hemagglutination titer was decreased by proteolytic enzyme treatments, but was not affected by glycosidase, lipase, phospholipase, and neuraminidase treatments. Cell-free hemagglutinin was found in supernatants of centrifuged sonicate and centrifuged agitate of H avium and was precipitated with ammonium sulfate with no loss of hemagglutinating activity. The H avium hemagglutinin showed different patterns of activity against the RBC of different avian species. Hemagglutination of chicken RBC was not inhibited by D-mannose.