IL4 and asthma: Adhesion assays with eosinophil reveal that IL-4 increases VCAM-1 expression in airway endothelial cells and results in the increased adhesion of eosinophils to VCAM-1 on the cells, emphasizing that the adhesion of eosinophil with VCAM-1 may play a central role in the pathogenesis of asthma.