Schwann Cells of the Bone Marrow

Nerves containing numerous Schwann cells can be found in bone marrow with routine histological methods. Thin nerve bundles and single nerve fibers containing Schwann cells can be identified histologically with help of methods which demonstrate nerve fibers and myelin. Smears of marrow stained with the May-Grünwald-Giemsa method are not adequate for demonstration of nerve fibers, but their satellite Schwann cells appear well stained. Histological, cytological and ultrastructural characteristics of these cells are described in detail. Blood-forming cells and nerve fibers with their Schwann cells lie in close proximity throughout the marrow. This circumstance suggests that interaction may take place between both elements.