RESUMO
Three leukemic cell lines were established from the bone marrow cells of two adolescents with non-T,non-B acute lymphoblastic leukemia (ALL) at relapse. Two cell lines from a 14-year-old girl and one from an 11-year-old boy were designated as KH-3A, KH-3B and KH-4, respectively. Leukemic cells started to grow attached to the bone marrow stromal (BMS) cells. KH-3A was positive for OKIa1 and positive at low percentages for B1, Leu-1 and J5 antigens; KH-3B reacted with OKIa1 and J5. Except for OKIa1, these two cell lines showed no surface marker change after 12-O-tetradecanoylphorbol-13-acetate (TPA) treatment. On TPA treatment, clones (KH-3A-2 and KH-3A-3) isolated from KH-3A in agarose showed the induction of differentiation into T and B cell lineage. KH-4 was positive for OKIa1 and positive at low percentages for B1 and J5, and showed a strong reaction with OKIa1, B1 and J5 after TPA treatment. T cell receptor (TCR) beta-chain gene and immunoglobulin gene (JH and C mu) rearrangements were found in KH-3A, KH-3B, and sublines isolated from KH-3 (KH-3A-2 and -3) simultaneously. These findings indicate that BMS cells are useful for the establishment of leukemic cell lines and that some common ALL (cALL) cell populations may be heterogeneous.