Humoral response in blood group P phenotype persons subjected to an avian environment.

The avian environment contains among many antigens, the blood group substance P1-P1 antigen is present in certain Enterobacteriaceae found in bird droppings. Examples include Enterobacter, Klebsiella, E. coli, Enterobacter Haffniae and Proteus. P2 persons exposed to the avian environment may develop anti-P1 activity. A greater percentage of precipitins to bird antigens was found in P2 than in P1 persons. In P1 persons seven out of twenty-eight (25%) had precipitins to bird droppings. In P2 persons, ten out of thirteen (77%) had anti-P1 activity and nine out of thirteen (69%) had precipitins to bird droppings. This greater response in P2 persons may be explained by the constant stimulation of these persons lacking the P1 antigen that triggers more response with other antigens in addition to the P1 antige. In the study of immunological responses to inhaled antigens, the blood group of the patients should be determined in order to assess the importance of constant stimulation by foreign material in persons lacking some blood group antigens.