Stave cells are seen in

sinusoids of the spleen - The sinusoids of the spleen are lined by a somewhat modified endothelium. The endothelial cells here are elongated and are shaped like bananas. They are referred to as stave cells. With the EM a system of ultramicroscopic fibrils is seen to be present in their cytoplasm. The fibrils may help to alter the shape of the endothelial cells thus opening or closing gaps between adjoining cells. The spleen acts as a filter for worn out red blood cells. Normal erythrocytes can change shape and pass easily through narrow passages in penicilli and ellipsoids. However, cells that are aged are unable to change shape and are trapped in the spleen where they are destroyed by macrophages. REF : Inderbir Singh's Textbook of Human Histology, Seventh edition, pg.no., 136, 137.