EXPRESSION OF ADHESION MOLECULES ON GRANULOCYTES AND MONOCYTES FROM PATIENTS WITH ASTHMA STIMULATED IN-VITRO WITH INTERLEUKIN-8 AND MONOCYTE CHEMOTACTIC PROTEIN-1

Upregulation of adhesion molecule expression on endothelial cells (EC) and circulating leukocytes, by locally produced inflammatory mediator s, may result in the enhanced infiltration of leukocytes into tissue, e.g. the airways of asthma patients. The present study investigates wh ether the expression of adhesion molecules on granulocytes and monocyt es from asthma patients is affected by chemotactic factors, i.e. inter leukin-8 (IL-8) and monocyte chemotactic protein-1 (MCP-1). Flow cytom etric analysis showed that the intrinsic expression of the various adh esion molecules on peripheral blood phagocytes from asthma patients wa s not different from that of healthy individuals. However, stimulation of monocytes with MCP-1 resulted only in upregulation of the expressi on of CD14 on monocytes from symptomatic asthma patients but not on mo nocytes from asymptomatic asthma patients and healthy individuals. Sti mulation of granulocytes with IL-8 did not change the expression of th e various beta(1)- and beta(2)-integrin molecules, such as VLA-4, LFA- 1, CR3 and p150,95. Since earlier studies have shown that CD14 on mono cytes mediates monocyte adhesion to activated vascular EC the present findings suggest that during the active phase of asthma upregulation o f CD14 on monocytes by MCP-1 may lead to an increased adhesion of mono cytes to vascular endothelium and their subsequent transendothelial mi gration into the tissue of the airways.