ALTERED EXPRESSION OF ADHESION MOLECULES (L-SELECTIN AND MAC-1) ON GRANULOCYTES DURING STORAGE

Background:The success of granulocyte transfusion therapy for neutrope nic patients with sepsis is dependent on the number and quality of the granulocytes transfused. There is a progressive impairment in granulo cyte function during storage. Study Design and Methods: The effect of 1 to 2, 4, 24, and 48 hours' storage on receptor expression associated with granulocyte function has been analyzed. Results: After 24 hours' storage, significant changes were found in the expression of receptor s associated with adhesion to the endothelium: a decrease in L-selecti n expression (p<0.01) and an increase in Mac-1 expression (p<0.01). Re ceptors (CR1 and FcRIII), associated with adhesion to target, were eit her increased (CR1) or unaltered (FcRIII). The capacity to produce a r eactive oxygen metabolite (hydrogen peroxide) remained essentially unc hanged after 48 hours' storage. The ability of N-formyl-methionyl-leuc yl-phenyl alanine to mobilize Mac-1 and CRI was reduced after 48 hours ' storage. Conclusion: Since the regulation of adhesion molecules is i mportant for the recruitment of granulocytes into an inflammatory site , the observed in vitro changes in L-selectin and Mac-1 expression dur ing storage may be of importance for the quality of granulocyte concen trates.