Increased levels of circulating autoantibodies to cultured human bronchialepithelial cell in adult patients with nonatopic asthma

The pathogenetic mechanism of nonatopic asthma has not yet been defined. Th e idea of a possible involvement of autoimmunity in the pathogenesis of non atopic asthma has been proposed by earlier studies. To evaluate the possibl e involvement of autoimmune response against bronchial epithelial cell in t he pathogenesis of nonatopic asthma, we measured circulating autoantibodies to cultured human bronchial epithelial cell (BEAS-2B cell line) using enzy me-linked immunosorbent assay. We used stored serum samples form 38 age-mat ched healthy controls, 26 adult patients with atopic asthma, 16 adult patie nts with nonatopic asthma, and 12 adult patients with systemic lupus erythe matosus. Levels of IgG autoantibodies to bronchial epithelial cell were sig nificantly higher in patients with nonatopic asthma (mean SD of absorbance values; 0.135 +/- 0.030) and systemic lupus erythematosus (0.293 +/- 0.181) than in healthy controls (0.112 +/- 0.016) and patients with atopic asthma (0.116 +/- 0.031) (p < 0.05). This study showed that levels of circulating IgG autoantibodies to bronchial epithelial cell were increased in adult pa tients with nonatopic asthma. Further studies are needed to evaluate the po ssible involvement of autoimmune mechanism in the pathogenesis of nonatopic asthma.