Evaluation of lymphocyte subsets after autologous bone marrow transplantation with marrow treated by ASTA Z 7557 in acute leukemia: incidence of the in vitro treatment.

The lymphocyte subset reconstitution after high-dose chemotherapy and total body irradiation followed by autologous bone marrow transplantation (ABMT) has been studied in ten patients with acute leukemia (AL) (6 ALL and 4 ANLL) in complete remission (CR). Bone marrow was treated in vitro with high-dose ASTA Z 7557, individually determined according to CFU-GM sensitivity. The different peripheral blood lymphocyte subsets were characterized by means of monoclonal antibodies (indirect immunofluorescence assay) belonging to the following classes of differentiation: OKT11-T11 (CD2), OKT3-T3 (CD3), OKT4-T4 (CD4), OKT8-T8 (CD8), OKIal-I2 (HLA-DR), Leu7 (natural killer/killer) and by means of polyspecific antiimmunoglobulin sera (direct immunofluorescence assay). Data in these ten patients were compared with those of a control group of 21 normal donors and with a control group of 14 patients in CR without ABMT. Our results showed a marked depression of the T4:T8 ratio in patients with AL before ABMT, compared with normal donors who had respective values of 1.02 and 1.33 (p less than 0.01). This depression was increased and prolonged up to day 515 after ABMT, with a value of 0.32 (p less than 0.01 compared with the pregraft situation; p less than 0.001 compared with normal donors). This T4:T8 ratio imbalance was related to the depletion of the T4+ population and to the increase of the T8+ subset. This imbalance was emphasized after ABMT. The Leu 7+ population was also increased in grafted patients compared with normal donors (p less than 0.01). The B-cell population remained unchanged throughout the study. We conclude that patients autografted with marrow treated in vitro by high-dose ASTA Z 7557 may experience a long-term T-cell subset imbalance.