Pigeon breeders' disease: quantitative immunoelectrophoretic studies of pigeon bloom antigen

Summary This study employed quantitative immunoelectrophoretic techniques, on sera from confirmed cases of pigeon breeders' disease (PBD), to investigate the antigenicity of a pigeon bloom extract, implicated as a sensitizing agent in this disease. On crossed immunoelectrophoresis the maximum number of antigenic components identified was 29 for the bloom compared to 10 for pigeon serum. A majorcomponent was shown to be closely related to pigeon IgA, and demonstrated partial crossreactivity to the pigeon IgG. This component also showed identity with the major component of a pigeon droppings extract, considered to be derived from intestinal IgA. Only trace amounts of serum albumin were detected and most other bloom components were not serum‐related. Although greater overall antigenic similarity was found to pigeon droppings extract, at least three of the bloom components appeared to be specific. The bloom extract also contained a low amount of an α‐techoic acid‐like component, causing some non‐specific reactivity. Pigeon feather dust or ‘bloom’, like pigeon droppings, is therefore a potent source of antigens associated with PDB–pigeon IgA being a major component of both antigens.