SUCCESSFUL HEMATOPOIETIC RECONSTITUTION WITH TRANSPLANTATION OF ERYTHROCYTE-DEPLETED ALLOGENEIC HUMAN UMBILICAL-CORD BLOOD-CELLS IN A CHILDWITH LEUKEMIA

Cord blood, a potent source of hematopoietic stem cells, has been show n to successfully reconstitute hem atopoiesis following allogeneic tra nsplantation in a variety of disorders. A major drawback of cord blood has been the risk of transfusion reactions in ABO blood group incompa tibility and drastic reduction in the stem cell pool if the cord blood is manipulated to remove red cells prior to cryopreservation or after thawing. This report describes an erythrocyte depletion method employ ing 3% gelatin-induced erythrocyte sedimentation for the selective rem oval of red cells from cord blood. The red cell-depleted fraction was shown to be enriched in progenitor cells and in cells secreting hemato poietic cytokines interleukin 3, granulocyte/macrophage colony-stimula ting factor, and interleukin 6; a major source for cytokines was from cord T cells. This preparative technique was employed to separate out red cells from cord blood of an infant delivered by cesarean section w ho had an 8-year-old sibling with leukemia. Histocompatibility testing of cord cells revealed complete matching with the patient. A cord cel l transplant of cryopreserved and thawed cells consisting of 4 x 10(7) nucleated cells per kg was administered to the patient following myel oablative chemotherapy. The patient's quick hematologic recovery and 9 -month disease-free period to date suggest that 3% gelatin separation of erythrocytes is a simple method that can be successfully used for t ransplanting cord cells for malignant/nonmalignant diseases.