T-lymphocytes are important components of the inflammatory cell infiltrate in bronchial mucosa in asthma. Because activated lymphocytes migrate through the thoracic duct and the general circulation to remote glandular and mucosal sites, we initiated this study to evaluate the histologic abnormalities of a minor salivary gland (MSG) associated with bronchial asthma. Fifty-eight asthmatic patients were prospectively studied (37 women, 21 men; mean age, 54 +/- 6 yr). Twenty-nine patients had allergic asthma (AA) and 29 had nonallergic asthma (NAA). Results were compared with those obtained from 15 healthy control subjects and 15 nonasthmatic patients with chronic obstructive pulmonary disease (COPD). MSG was normal in 14 of 15 patients with COPD and in 14 of 15 control subjects. Forty-three of 58 (74%) asthmatic patients presented MSG abnormalities. These were significantly more frequent in asthmatics (74%) than in patients with COPD and healthy control subjects (6%, p < 0.001 versus asthmatics) and in NAA (97%) than in AA (52%, p < 0.01). The main pathologic features of MSG in asthma were T-lymphocyte infiltration (57%: AA nine of 29; NAA 24 of 29), partly degranulated mast cells (64%: AA, 11 of 29; NAA, 26 of 29), basement membrane thickening (64%: AA, 11 of 29; NAA, 26 of 29), and endothelial cell changes (26%: AA, one of 29; NAA, 14 of 29). Eosinophils were found only in two cases. Expression of ICAM-1 was demonstrated in nine of 16 patients with NAA, whereas VCAM-1 and E-selectin were negative in all of them.(ABSTRACT TRUNCATED AT 250 WORDS)