BRONCHIAL INFLAMMATION IN OCCUPATIONAL ASTHMA DUE TO WESTERN RED CEDAR

Bronchoalveolar lavage cells and bronchial biopsies were obtained from nine patients with red cedar asthma, six atopic asthmatics and six no n-atopic, non-asthmatic control subjects. There were similar proportio ns of neutrophils, mast cells, lymphocytes, and macrophages in BAL sam ples from all three groups, but eosinophil numbers were elevated in pa tients with cedar asthma and atopic asthma (3.0 and 2.5% respectively versus 0.5% in control subjects; p < 0.05 for each group). In bronchia l mucosal biopsies, mean numbers of T cells were elevated in both asth matic groups (cedar asthma 9.8 times, and atopic asthma 2.6 times, con trol values). CD4(+) cells accounted for most of the increase in T-cel l numbers, while CD8(+) cell numbers were elevated in biopsies from a minority of cedar asthma patients. Absolute numbers of CD25(+) (IL-2 r eceptor-bearing) cells were increased in cedar asthma but the proporti on of T cells expressing CD25, was similar in all three groups. Activa ted eosinophils (EG2(+)) were increased in both asthmatic groups, with mean numbers 2.5 times greater in the cedar asthma biopsies than in a topic asthmatics. Thus both cedar asthma and atopic asthma are associa ted with increased numbers of T-cells and activated eosinophils in the bronchial mucosa. There was no major histologic difference between at opic asthma and red cedar asthma.