Establishment and characterization of a human acute monocytic leukemia cell line (THP‐1)

Abstract A human leukemic cell line (THP‐1) cultured from the blood of a boy with acute monocytic leukemia is described. This cell line had Fc and C3b receptors, but no surface or cytoplasmic immunoglobulins. HLA haplotypes of THP‐1 were HLA‐A2, ‐A9, ‐B5, ‐DRW1 and ‐DRW2. The monocytic nature of the cell line was characterized by: (1) the presence of α‐naphthyl butyrate esterase activities which could be inhibited by NaF; (2) lysozyme production; (3) the phagocytosis of latex particles and sensitized sheep erythrocytes; and (4) the ability to restore T‐lymphocyte response to Con A. The cells did not possess Epstein‐Barr virus‐associated nuclear antigen. These results indicate that THP‐1 is a leukemic cell line with distinct monocytic markers. During culture, THP‐1 maintained these monocytic characteristics for over 14 months.