Macrophages are found in the subepithelial tissues of the skin, intestine and alveoli. These cells are appear as histiocytes. Other members of the macrophage family are found in tissue of the reticulo-endothelial sytem, in particular in subcapsular sinuses of the lymph nodes, in the spleen and as the Kupffer cells in the liver sinusoids.
CD14 acts as a receptor for bacterial lipopolysaccharide (LPS). Members of the integrin family will bind Leishmania, Bordetella, Candida as well as LPS.