Changes of soluble ICAM-1 levels in serum and bronchoalveolar lavage fluid from patients with atopic bronchial asthma after allergen challenge.

Leukocyte-endothelial cell interaction is essential for leukocyte infiltration into inflammatory sites. Initiation of adhesion is through the up-regulated expression of adhesion molecules in the endothelium or epithelium and the activation of adhesion molecules on leukocytes. To our knowledge, there have been few reports concerning soluble intercellular adhesion molecule-1 (sICAM-1) in patients with atopic bronchial asthma after allergen challenge. If the levels of sICAM-1 vary between bronchial asthma patients and normal controls, this variance would be useful to assess the state of this disease. Therefore, we measured the levels of sICAM-1 in sera from 17 patients with atopic bronchial asthma and normal control subjects. Levels of sICAM-1 in sera from bronchial asthma patients in prechallenge conditions were higher than in normal control subjects. Levels of sICAM-1 in sera from bronchial asthma patients 8 hr after challenge were higher than those in sera obtained during prechallenge periods. sICAM-1 levels in bronchoalveolar lavage (BAL) fluids from bronchial asthma patients 8 hr after challenge were higher than at 30 min after challenge. These results suggest that higher levels of sICAM-1 in sera and BAL fluids reflect the up-regulation of ICAM-1 expression in allergic bronchial asthma and these high levels may contribute to the pathogenesis of atopic bronchial asthma.