Cord-Placental Blood Banking

Summary

Cord-placental blood, a rich source of hemopoietic stem cells, has come to be used clinically for stem cell transplantations. With the cooperation of the obstetrics staff of the Japanese Red Cross Medical Center, cord blood was withdrawn in the 3rd stage of labor with the written consent of the mother. If the mother had a positive viral marker or if the baby had a genetic abnormality, then the cord blood was not withdrawn. The mean volume obtained was 32.5 ml. We used 10 ml of the blood mixed with anticoagulant for the cell count, blood typing, HLA typing and infectious marker screening, keeping the plasma and DNA frozen for future analysis. The samples were processed for RBC reduction with HES, analysed for colony forming ability and CD34⁺ population, and then frozen in liquid nitrogen. The frozen samples had a mean of 3.7 x 10⁸ nucleated cells, 1.5 x 10⁵ CFU-GM and 2.9 x 10⁵ CD34⁺ cells. As a source for collecting stem cells, cord blood is the least obtrusive for the donor. A limitation is the volume, with only a small proportion of the samples giving an adequate number of stem cells. While the cord blood samples with more than 5 x 10⁸ cells are few in number, they are ready to be used for transplantation, and the project is proceeding.