IRON CARBONYL, A TRACER FOR PHAGOCYTOSIS IN SCANNING ELECTRON-MICROSCOPY

  • 1 January 1982
    • journal article
    • research article
    • Vol. 32  (3) , 201-207
Abstract
Human peripheral blood mononuclear cells and polymorphonuclear (PMN) leukocytes, separated by Ficoll-Hypaque were incubated with a preparation containing iron carbonyl and studied by scanning electron microscopy (SEM) in the backscattered electron imaging (BEI) mode. Iron carbonyl particles were visible only on the cell surface when studied in the conventional secondary electron (SE) mode of SEM. Ingested iron carbonyl particles were observed in high contrast when the backscattered electrons were selectively collected. The BEI mode of the SEM appeared very useful in identifying phagocytic activity in mixed cell populations and in establishing direct correlations, at the level of each individual cell, between surface morphology and phagocytic activity.