title: Retinoic acid regulates IgG Fc receptor expression in human myelomonocytic leukemia cells and normal peripheral monocytes.
abstract: The regulation of IgG Fc receptor (Fc gamma R) expression by retinoic acid (RA) in human myelomonocytic cells at different stages of maturation was studied. RA suppressed IgG-coated erythrocyte (EA) rosette formation of myelomonocytic cells blocked at relatively late stages of differentiation such as ML-1, U-937, THP-1-T, normal monocytes, and fresh cells of patients with acute myelomonocytic leukemia. However, RA increased the percentage of EA rosetting promyelocytes of HL-60 and of patients with acute promyelocytic leukemia and a part of myeloblasts isolated from acute myelogenous leukemia patients. Other myeloblasts including KG-1a, KG-1, and fresh cells from patients with acute myelogenous leukemia were not affected. A kinetic study using HL-60 and THP-1-T demonstrated that an increase required at least a 48-h exposure and that the maximum decrease required approximately 6 h. The RA effect on both cell lines was dose-dependent. The number of Fc gamma R of HL-60 and THP-1-T treated with RA became very close, although untreated THP-1 had almost 10 times as many as HL-60. Kd for IgG in both THP-1-T and HL-60, either untreated or treated with RA, remained unchanged. These observations indicate that one of the important roles of RA is regulation of Fc gamma R expression in myeloid cells.
authors.affiliation: Department of Bacteriology, Tohoku University, School of Medicine, Sendai, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Nakamura
authors.forename: H
authors.initials: H
authors.lastname: Hemmi
mesh_terms: D000943:Antigens, Differentiation / Q000378:metabolism*; D001665:Binding Sites / Q000187:drug effects; D002454:Cell Differentiation / Q000187:drug effects; D002460:Cell Line; D006801:Humans; D007074:Immunoglobulin G / Q000378:metabolism*; D007700:Kinetics; D015479:Leukemia, Myelomonocytic, Acute / Q000276:immunology* / Q000473:pathology; D009000:Monocytes / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D011961:Receptors, Fc / Q000378:metabolism*; D017452:Receptors, IgG; D012397:Rosette Formation; D014212:Tretinoin / Q000494:pharmacology*
chemical_list: D000943:Antigens, Differentiation; D007074:Immunoglobulin G; D011961:Receptors, Fc; D017452:Receptors, IgG; D014212:Tretinoin