Lung-reactive antibodies in sera of patients with farmer's lung disease.

Lung-reactive antibodies were detected in sera of patients with farmer's lung disease and in sera of healthy persons. A solid-phase radioimmunoassay was adapted for measurement of titers of human antibodies to sodium-dodecyl-sulfate-solubilized lung proteins. The titers of antilung antibodies in patients sera were 2-5 times as much as those of healthy persons. Using the immunoblotting technique, antibodies to individual lung polypeptides could be detected. Although the specificity patterns of antibodies to lung polypeptides differed from one serum to another, patients sera contained, in general, antibodies to larger numbers of lung polypeptides as compared to sera of healthy persons. The relationship between antilung antibodies and hypersensitivity pneumonitis is discussed.