Cytogenetic studies on recipients of allogeneic bone marrow using the sex chromosomes as markers of cellular origin

Abstract

In 45 patients whose donor was of unlike sex, the sex chromosomes were used as markers of the cellular origin of myeloid and lymphoid tissues after allogeneic bone marrow transplantation (BMT). Successful engraftment was characterized by the appearance of dividing donor cells in marrow within 2 wk of grafting and in mitogen stimulated blood cultures by 3 wk. Leukemic relapse was identified in 8 cases and was associated with different patterns of cellular origin of the myeloid and lymphoid tissues. At the time of relapse the marrow contained either a mixed population of normal donor and leukemic recipient cells, or only recipient cells. Leukemic relapse was not found occurring in donor cells. The importance of defining the origin of cells in interphase as well as in metaphase was demonstrated. In all but 1 case, the dividing lymphoid population remained of donor origin during relapse.