Immunogold labeling for myeloperoxidase of neutrophils at different stages of their emperipolesis within GATA-1low MKs. Examples of neutrophils approaching the MK (A), penetrating the MK through the DMS (B), and embedded in the MK cytoplasm (C). The rectangle in each panel indicates the area shown at higher magnification in the insert. The arrows indicate isolated as well as clustered gold particles. The arrowheads in the panels indicate the extracellular membrane of the MK; those in the inserts, the neutrophil/MK border. Immunogold particles are localized only in the neutrophil in panel A, on both sides of the neutrophil-MK border in panel B, and on both sides of the neutrophil/MK border and on the extracellular side of the MK membrane in panel C. Original magnification × 3000 for all panels and × 30 000 for the inserts.
