01931nas a2200373   4500000000100000008004100001260001300042653002700055653004600082653002000128653002500148653001600173653001900189653001100208653002800219653002200247653002100269653001600290653002100306653001400327100001500341700002100356700001300377700001500390700001700405700001800422700001400440700001500454245010100469300001100570490000700581520095500588022001401543       1989                            d  c1989 Aug10aAntibodies, Monoclonal10aAntigens, Differentiation, Myelomonocytic10aBlood Platelets10aCell Differentiation10aEndothelium10aFlow Cytometry10aHumans10aImmunoenzyme Techniques10aInterferon Type I10aInterferon-gamma10aMacrophages10aMolecular Weight10aMonocytes1 aCabañas C1 aSanchez-Madrid F1 aBellon T1 aFigdor C G1 aTe Velde A A1 aFERNANDEZ J M1 aAcevedo A1 aBernabeu C00aCharacterization of a novel myeloid antigen regulated during differentiation of monocytic cells.  a1373-80 v193 a<p>The monoclonal antibody HC1/6 generated against phorbol 12-myristate 13-acetate-treated U-937 cells recognizes a new cell surface antigen with a broad relative molecular mass ranging from 100 to 150 kDa. This antigen is also present on monocytes, platelets and endothelial cells and is weakly expressed by granulocytes. In contrast, it is absent from T, B and erythroblastoid cells. The antigen HC1/6 is also expressed by normal tissue macrophages in tonsil, lung and kidney, as well as in skin biopsies from pathologies such as sarcoidosis and lepromatous leprosy. The expression of the HC1/6 antigen is increased up to 5-fold when U-937 (promonocytic) and HL-60 (myelomonocytic) cell lines are stimulated with phorbol 12-myristate 13-acetate. Conversely, the expression of the HC1/6 antigen is down-regulated in monocytes upon treatment with interferon-gamma. These findings are discussed in relation with other myeloid cell surface markers.</p>  a0014-2980