In this set of images, you can see histiocytes in normal bone marrow aspirate sample of a young adult.

Histiocytes are differentiated cells that originated from macrophages and/or dendritic cells and settled in tissues. These cells have different tasks depending on their location.

The main role of these cells in bone marrow is to remove cellular debris (mainly old red blood cells). Also, these cells are a source of stored iron in bone marrow. Compared to macrophages, histiocytes show less number of lysosomal granules, therefore their phagocytic function is less than a macrophage.