Altered expression of adhesion molecules (L-selectin and Mac-1) on granulocytes during storage

The success of granulocyte transfusion therapy for neutropenic patients with sepsis is dependent on the number and quality of the granulocytes transfused. There is a progressive impairment in granulocyte function during storage.

The effect of 1 to 2, 4, 24, and 48 hours' storage on receptor expression associated with granulocyte function has been analyzed.

After 24 hours' storage, significant changes were found in the expression of receptors associated with adhesion to the endothelium: a decrease in L-selectin expression (p < 0.01) and an increase in Mac-1 expression (p < 0.01). Receptors (CR1 and FcRIII), associated with adhesion to target, were either increased (CR1) or unaltered (FcRIII). The capacity to produce a reactive oxygen metabolite (hydrogen peroxide) remained essentially unchanged after 48 hours' storage. The ability of N-formyl-methionyl-leucyl-phenyl alanine to mobilize Mac-1 and CR1 was reduced after 48 hours' storage.

Since the regulation of adhesion molecules is important for the recruitment of granulocytes into an inflammatory site, the observed in vitro changes in L-selectin and Mac-1 expression during storage may be of importance for the quality of granulocyte concentrates.