Characteristics of small monocytoid cells produced by nurse macrophages.

<p>(A) Immunophenotype of nonadherent small monocytoid cells (SMC) harvested from an 18-day-old MDM culture. White arrow (top left plot) identifies the gated population shown in other plots. (B) Forward scatter (FSC) versus side scatter (SSC) plot demonstrates that SMC (CD3negCD4dimCD14+) are smaller than resting lymphocytes. Cells from 17-day-old MDM. Analysis performed using Paint-a-Gate software. (C) Confocal microscopy demonstrating that SMC adhere following their exit from nurse macrophages. Shown here is an 18-day-old primary MDM culture. An SMC adhering to a large macrophage (green arrow) and another adhering to the culture dish (pink arrow) can be seen. Others with elongated processes are also visible (white arrows) and viewable in greater detail in the panel on the right. The pink color of the nuclei reflects cdc6 colocalization with DNA as identified by TOTO-3 staining. SMC nuclei are typically cdc6+ during and shortly after budding from nurse macrophages, reflecting recent DNA synthesis. Size bar: 50 µm.