Importance of marrow dose on posttransplant outcome in acute leukemia: models derived from patients autografted with mafosfamide-purged marrow at a single institution.

Several prospective randomized trials in acute myelocytic leukemia (AML) documented a lower relapse rate with autologous bone marrow transplantation (ABMT) than with conventional chemotherapy. However, they also identified some transplant difficulties, such as failure to collect sufficient numbers of stem cells, slow kinetics of engraftment, and a high transplant-related mortality that diminished or negated positive impact on overall survival. Data for ABMT are inconclusive in acute lymphocytic leukemia (ALL) in adults. We retrospectively analyzed patients with acute leukemia autografted with marrow purged with mafosfamide after January 1983 in our institution. The population comprised 229 consecutive patients; 165 with AML [123 in first remission (CR1), 32 in second remission (CR2)]; 61 with ALL (46 in CR1, 4 in CR2); and 3 with undifferentiated acute leukemia. All patients were autografted with marrow purged with mafosfamide. Mafosfamide was given at a constant dose of 50 microg/mL in 103 and adjusted individually to produce a CFU-GM LD 95 (5% residual CFU-GM post purging) in 126. The outcome was analyzed for correlation with patient characteristics, the disease including cytogenetics, and the graft itself. Prognostic factors identified by multivariate analysis were used to derive a prognostic classification. Patients receiving higher doses of marrow submitted to purging (>5.46 x 10(4) CFU-GM/kg) experienced a lower treatment-related mortality (RR = 0.11, p = 0.005) and a higher leukemia-free (RR = 0.5, p = 0.005) and overall survival (RR = 0.4, p = 0.001). Patients receiving <0.004% CFU-GM of marrow actually infused post purging had a lower relapse rate (RR = 0.51, p = 0.003). Modeling of prognostic groups identified good-, intermediate-, and poor-risk categories. Patients receiving a stem cell dose evaluated before purging of >5.46 x 10(4) CFU-GM/kg and doses actually infused post purging of < or =0.02 x 10(4)/kg had a treatment-related mortality of only 2+/-2%, a leukemia-free survival of 70%, and an overall survival of 77+/-7% at 10 years. In this study of autotransplantation for acute leukemia using mafosfamide-purged marrow, the stem cell dose used for purging and the intensity of purging were the most important factors predicting outcome.

The frequency of HIV-specific interferon- gamma -producing CD8 T cells is associated with both age and level of antigenic stimulation in HIV-1-infected children.

Ex vivo interferon (IFN)- gamma -producing CD8 T cells specific for human immunodeficiency virus (HIV) Env, Gag, and Pol antigens were measured in the peripheral blood of 55 children not receiving highly active antiretroviral therapy (HAART) and 70 children receiving HAART. In children not receiving HAART, the frequency of HIV-specific IFN- gamma -producing CD8 T cells was positively correlated with age and was not associated with plasma viral load or CD4 T cell levels. In children receiving HAART, the frequency of HIV-specific IFN- gamma -producing CD8 T cells was directly correlated with plasma viral load, and its association with age remained significant. In conclusion, the frequency of HIV-specific IFN- gamma -producing CD8 T cells in children is primarily determined by both age and plasma viral load.