Redistribution of membrane 5'-nucleotidase in rabbit peritoneal polymorphonuclear leucocytes during phagocytosis

Using a quantitative phagocytic model involving oil droplet internalisation rabbit polymorphonuclear leucocytes display selective segregation of membrane constituents during the phagocytic event. A resting cell surface membrane and fractions representing vesicle membranes and uninvolved surface membranes from the active cells have been purified by density gradient sedimentation and free flow electrophoresis. The specific activity of 5'-nucleotidase, a major neutrophil surface membrane glycoprotein, was 3-fold higher in the uninvolved membrane of phagocytosing cells than in the resting cell membrane. The activity in the vesicle membranes was substantially depleted. In contrast Lens culinaris receptors showed no redistribution during phagocytosis: the two surface domains showing essentially the same enrichment with respect to homogenate as the resting cell surface membrane.