CELL-SURFACE ANTIGEN EXPRESSION BY PERIPHERAL-BLOOD MONOCYTES IN ALLERGIC-ASTHMA - RESULTS OF 2.5 YEARS THERAPY WITH INHALED BECLOMETHASONEDIPROPIONATE

AT present, inhaled glucocorticoids are widely accepted as the therapy of choice in chronic asthma. Treatment with inhaled glucocorticoids s ignificantly suppresses local airway inflammation in asthmatics, but m ay also have systemic effects, e.g. a reduction of the number of circu lating hypodense eosinophils or a down-modulation of HLA-DR antigen (A g) expression by T lymphocytes in peripheral blood. However the effect of long-term therapy with inhaled glucocorticoids on peripheral blood monocytes (PBM), which are the precursors of the most numerous cell t ype in the lung, the alveolar macrophage, have not yet been evaluated. We therefore investigated the expression of various cell surface Ag o n PBM from non-smoking patients with allergic asthma who were treated for 2.5 years with a beta(2)-receptor agonist plus either an inhaled g lucocorticoid (beclomethasone dipropionate, BDP) (n = 4) or an anticho linergic or placebo (n = 8). We compared the results with healthy volu nteers (n = 7). Long-term treatment of allergic asthmatics with inhale d BDP, but not anticholinergic or placebo therapy, was associated with a significantly lower CD11b Ag expression (p < 0.04) and higher expre ssion of CD13, CD14 and CD18 Ag (p < 0.05, p < 0.02 and p < 0.04, resp ectively) when com pared with the healthy control subjects (n = 7). Mo st interestingly, PBM of asthmatics treated with inhaled BDP expressed an almost two-fold higher level of CD14 Ag on their cell surface than PBM of patients treated with anticholinergic or placebo (p < 0.03). N o significant differences in the expression of CD16, CD23, CD25, CD32 and CD64 Ag or HLA-DR were observed between PBM from the different pat ient groups or healthy controls. Taken together, this study shows that long-term local therapy with inhaled BDP coincides with an altered ex pression of at least one cell surface Ag on PBM from allergic asthmati cs.