Serum antibodies to pigeon antigens in smokers and nonsmokers.

Antibodies to pigeon antigens were determined by double immunodiffusion and ELISA in 80 pigeon breeders without pigeon breeder's disease. Precipitating antibodies to pigeon serum and droppings were found in 5 and 8%, respectively, of 39 breeders who were smokers and in 46 and 51%, respectively, of 41 breeders who were nonsmokers (p less than 0.001). By ELISA, IgG antibodies to pigeon serum and droppings were detected in 44 and 54%, respectively, of smokers and in 81 and 85%, respectively, of nonsmokers (p less than 0.01). The antibody titres were generally higher in nonsmokers than in smokers. These findings may partly explain why allergic alveolitis occurs most often in nonsmokers.