ERYTHROCYTE-DEPLETED ALLOGENEIC HUMAN UMBILICAL-CORD BLOOD TRANSPLANTATION

Cord blood is a recently recognized source of hematopoietic stem cells. It can be employed successfully to reconstitute hematopoiesis following allogeneic transplantation. One current drawback of cord blood as a treatment has been a risk of transfusion reactions attributable to ABO blood group mismatch, Removal of red cells from the cord blood has led to reduction of the stem cells by 30-50%, In this paper we report red cell depletion by a method that employs 3% gelatin to effectively sediment the erythrocytes and selectively deplete red cells but permits 94% recovery of nucleated cells and enrichment of colony-forming cells by granulocyte-macrophage colony-forming units, erythrocyte burst-forming units, and granulocyte-macrophage-megakaryocyte colony-forming units in the cord blood preparation, This technique has been employed in our study to remove red cells from the cord blood of a male infant delivered by cesarean section, which has permitted treatment of a female sibling suffering from leukemia, The recipient was 8 years old and weighed 36.7/kg, Complete HLA identity between the two siblings was established, A cord blood cell transplant of cryopreserved and later thawed cells (4 x 10(7) nucleated cells per kilogram) was administered to the patient after intensive myeloablative chemotherapy, The patient exhibited a prompt hematologic recovery (absolute neutrophil count >500 by day 31, 100% male cells in bone marrow and peripheral blood by day 25) and has experienced a 13-month disease-free survival to date. These findings suggest that this method of gelatin separation of erythrocytes represents a simple and effective technique that can be used for reducing cord blood red cells and at the same time permit use of the remaining stem cells for transplantation and for the treatment of either malignant or nonmalignant disorders,