Soluble intercellular adhesion molecule 1 (ICAM-1) antigen in sera of bronchial asthmatics.

Previous studies have suggested that intercellular adhesion molecule 1 (ICAM-1, CD54) may be involved in the pathogenesis of asthma. In addition, a soluble form of ICAM-1 (sICAM-1) has been detected in increased concentrations in the sera of patients with certain inflammatory conditions. To determine whether bronchial asthma is associated with increased levels of sICAM-1 in serum and to assess the effects of therapy on these levels, the concentrations of sICAM-1 were measured in sera of healthy donors and asthmatic patients. The mean (+/- SD) level of serum sICAM-1 for 60 asthmatic patients (304.0 +/- 82.5 ng/mL) was significantly higher than that for 39 healthy volunteers (260.9 +/- 67.2 ng/mL; p = 0.004). Twenty-two patients considered to have atopic asthma and 24 patients with nonatopic asthma did not differ in their levels of sICAM-1. In 14 patients, serum concentrations of sICAM-1 were higher during asthma attacks than in the same patients during remission (p = 0.035). Serum sICAM-1 levels were lower in nine patients during treatment with oral prednisolone (2.5 to 40 mg/d) than during periods without systemic corticosteroid therapy (p = 0.002). Thus, active bronchial asthma is associated with the presence of increased levels of sICAM-1 in serum, and these levels may be modulated by corticosteroid therapy.