In vitro incubation of bone marrow and peripheral stem cells with vincristine and methylprednisolone: functional T-cell depletion for haploidentical and autologous transplants.

A mismatched bone marrow transplantation is feasible only if the donor's marrow lymphocytes are eliminated from the graft. This can be achieved by several methods, but all have the disadvantage of inducing a long-lasting immune deficiency while the risk of graft rejection and leukemic relapse increase. We use a sort of functional T-cell depletion by treating the cells with vincristine and methylprednisolone. This method is surely the cheapest and has allowed us to perform 60 transplants with a tolerable risk of GVHD. The treatment of the donor's lymphocytes has already been demonstrated to be able to block the mixed lymphocyte culture reaction in vitro. In this experiment Th1 and Th2 activities were almost completely blocked without reduction of lymphocyte viability and apoptosis induction.