Expression of a calcium binding protein pEL98 (mts1) during differentiation of human promyelocytic leukemia HL-60 cells.

The expression of pEL98 (also termed mts1), an S100-related calcium-binding protein, was induced during macrophagic or granulocytic differentiation of human promyelocytic leukemia HL-60 cells in response to phorbol 12-myristate 13-acetate or dimethylsulfoxide, respectively. However, pEL98 expression remained at the low level during granulocytic differentiation of the cells by the treatment with all-trans retinoic acid. The expression of cell motility, but not adhesiveness or phagocytic ability, was found to be coincided with that of pEL98 (mts1), suggesting that pEL98 (mts1) is involved in regulating cell motility. Immunocytochemical analysis demonstrated that pEL98 (mts1) was expressed in human monocytes, macrophages and polymorphonuclear leukocytes.