Macrophages of Hypothalamic Third Ventricle

Abstract

The question of whether hematogenous macrophages are present in the brain has remained incompetely resolved for many years. In the present study, a modified tissue culture system was employed, which enabled the isolation and visualization of cells which migrated from the surface of the hypothalamic third ventricle. Cultured cells were examined for macrophage characteristics, such as surface fine structure and cell spreading, phagocytic activity, nonspecific esterase activity, and the presence of cell surface receptors for the Fc portion of the immunoglobulin IgG. Markers of these characteristics were correlated cell by cell with light microscopy and scanning electron microscopy, utilizing both secondary and back-scattered electron imaging. Cells with all characteristic markers of the monocyte/macrophage line were identified and represent ventricular macrophages.