CD99 is expressed on all leukocytes (the cells of the immune system that are involved in protecting the body against both infectious disease and foreign invaders) but highest on thymocytes and is believed to augment T-cell adhesion and apoptosis of double positive T cells, and has been found in endothelial cells and in the periodontium, including gingival fibroblasts and gingival epithelial cells.
CD99 is expressed on all leukocytes (the cells of the immune system that are involved in protecting the body against both infectious disease and foreign invaders) but highest on thymocytes and is believed to augment T-cell adhesion and apoptosis of double positive T cells, and has been found in endothelial cells and in the periodontium, including gingival fibroblasts and gingival epithelial cells.