CD146 - BIOSYNTHESIS AND PRODUCTION OF A SOLUBLE FORM IN HUMAN CULTURED ENDOTHELIAL-CELLS

We previously identified the S-Endo 1-associated antigen (CD146), an e ndothelial member of the immunoglobulin superfamily with a characteris tic V-V-C2-C2-C2 Ig domain structure, In cultured human endothelial ce lls, we investigated its biosynthesis by immunoprecipitation and pulse -chase labeling., CD146 was synthesized as a 100 kDa precursor form, w hich was processed into a 120 kDa mature form, In the culture media of endothelial cells, we observed a CD146 soluble form that,vas about 10 kDa smaller than cell-associated CD146. In parallel with soluble form s of other members of the immunoglobulin superfamily, soluble CD146 co uld modulate and control the functions of the molecule, (C) 1998 Feder ation of European Biochemical Societies.