Soluble intercellular adhesion molecule-1 (slCAM-1) and interferon-gamma in bronchoalveolar lavage fluid from children with airway diseases

We have previously described that in bronchoalveolar lavage fluid (BALF), e osinophils characterize asthma and neutrophils are more prominent in infant ile wheeze. In this study, we hypothesized that intercellular adhesion mole cule 1 (ICAM-1) and interferon-gamma (IFN-gamma) would have a role in promo ting migration of both cell types into the airway. To investigate this, we measured soluble (s) ICAM-1 in 68 BALFs from infants and young children wit h various respiratory problems. Children with asthma were characterized by significantly raised sICAM compared with those with chronic cough without w heeze (p = 0.05) or control subjects with no lower airway pathology (p = 0. 045). The levels correlated with disease severity (evaluated with a symptom score) and with lymphocyte numbers. IFN-gamma levels were also raised in c hildren with asthma compared with those with chronic cough (p = 0.05), but there was no correlation with disease activity. Infantile wheeze was charac terized by a linear correlation between sICAM-1 and IFN-gamma (r = 0.55; p = 0.002). sICAM-1 levels in infantile wheeze correlated with the severity o f the disease and lymphocyte numbers. IFN-gamma levels were elevated in the wheezers treated with inhaled steroids compared with untreated infants (p = 0.03). Although sICAM-1 levels were increased in those with severe cough, no characteristic inflammatory profile was found in the group with chronic cough. Our study suggests that ICAM-1 and IFN-gamma play a role in the act ivity of the inflammatory process in asthma in childhood and possibly in so me infant wheezers, in whom IFN-gamma may be one of the factors increasing the expression of ICAM-1. The role of IFN-gamma, a T helper-1 cytokine, in children with asthma remains to be fully understood.