Human monocytic leukemic cell line THP-1 was incubated with transforming growth factor-beta 1 (TGF-beta 1) and retinoic acid (RA) and the expression of Fc gamma RIII was investigated. Fc gamma RIII was induced after incubation of the cells with both TGF-beta 1 and RA but not with either TGF-beta 1 or RA alone. Such effects of TGF-beta 1 and RA were not detected on human promyelocytic HL-60 cells. Northern blot analysis revealed the induction of Fc gamma RIII transcripts in THP-1 cells. Furthermore, the Fc gamma RIIIs newly expressed on the cell surface were cleaved by phosphatidylinositol-specific phospholipase C (PI-PLC) and reacted with monoclonal antibody MG38 which specifically binds to granulocyte-type Fc gamma receptors. These results indicated that TGF-beta 1 could induce phosphatidylinositol-glycan-linked Fc gamma RIII (Fc gamma RIII-I) in THP-1 cells in the presence of RA.