Single chain membrane glycoprotein, a lipopolysaccharide binding protein complex receptor, 53-55 kDa. CD14 is receptor for endotoxin and apoptotic cells. It is expressed by monocytes/histiocytes, Langerhans' cells, follicular dendritic reticulum cells, neutrophils (weakly), and endothelial cells of the liver sinusoids. In few studies non-hepatic endothelial cells have shown a weak CD14 expression. Experimentally, a subpopulation of circulating endothelial cell progenitors are CD14 positive. Probably, these cells are monocyte derived.
CD14 is detected in myeloid leukaemias with monoblastic/monocytic differentiation, and in histiocytic neoplasms like histiocytic lymphoma, Langerhans' cell histiocytosis and giant cell tumour. In cultures, a subpopulation of Kaposi sarcoma cells express CD14.
CD14 is more specific than CD68 in the identification of monocytes/histiocytes and associated neoplasias. CD14 also detects follicular dendritic reticulum cells.
Scott CS, Richards SJ, Master PS, Kendall J, Limbert HJ, Roberts BE. Flow cytometric analysis of membrane CD11b, CD11c and CD14 expression in acute myeloid leukaemia: relationships with monocytic subtypes and the concept of relative antigen expression. Eur J Haematol. 1990 Jan;44(1):24-9. Wright SD, Ramos RA, Tobias PS, Ulevitch RJ, Mathison JC. CD14, a receptor for complexes of lipopolysaccharide (LPS) and LPS binding protein. Science 1990;249:1431-3.