Clustering on the forward surfaces of migrating neutrophils of a novel GPI-anchored protein that may regulate neutrophil adherence and migration

We previously reported a novel glycosylphosphatidylinositol (GPI)‐anchored glycoprotein (tentatively designated GPI‐80) on human leukocytes that may be involved in the regulation of neutrophil adherence and migration. In this study, we examined by immuno‐ and scanning electron microscopy, the distribution of GPI‐80 on neutrophil surfaces. GPI‐80 was diffusely distributed on the surface of resting neutrophils and on the peripheral areas of adherent cells after stimulation with N‐formyl‐methionyl‐leucyl‐phenylalanine. After longer stimulation (60 min), GPI‐80 decreased in number and was again diffusely distributed on the surfaces of round neutrophils. Few GPI‐80 were detected on the ventral surfaces of adherent neutrophils. Clusters of GPI‐80 were detected on the forward surfaces of neutrophils transmigrating through pores of nitrocellulose membranes. These results may give a morphological background of possible role of GPI‐80 for neutrophil extravasation.