Identical reconstitution after bone marrow transplantation in twins who received fresh and cryopreserved grafts harvested at the same time from their older brother

Abstract

We report here the reconstitution after bone marrow transplantation (BMT) in identical infant twins with acute myelogenous leukemia (AML). They were diagnosed at 8 and 9 months of age. Complete remission was induced after two courses of chemotherapy. After four and five courses of chemotherapy, respectively, they received BMT at 2-month interval from the same HLA-identical older brother. The total dose of marrow nucleated cells (NC) harvested was 77.7 x 10(8). The first patient was transplanted with half of the total dose of NC. The remaining cells were cryopreserved without the use of a programmed freezer and transplanted into the second patient 2 months later. The number of days for neutrophil (>0.5 x 10(9)/L), platelet (>50 x 10(9)/L), and reticulocyte (>1%) recovery were, respectively, 15, 21, and 14 in the first case and 12, 21, and 15 in the second case. The clinical courses after BMT were uneventful in both cases, except for mild acute GVHD, and complete remission has been maintained >4 yr with full recovery of immune and marrow function. Based on the results in these cases, we confirmed that marrow cells that have been cryopreserved without the use of a programmed freezer could reconstitute immune and marrow function as well as non-cryopreserved cells.