Objective: To study the influence of cord blood total nucleated cell (TNC) dose on the efficacy of cord blood transplantation in children.
Methods: Thirty-four children with hematological disease received cord blood transplantation. They were assigned to 3 groups according to the infused TNC dose: TNC>10 x 10(7)/kg (n=7), 10 x10(7)/kg>TNC> or =7 x 10(7)/kg (n=9) and TNC<7 x 10(7)/kg (n=18). The rates of graft and rejection of hematopoietic stem cells and the efficacy of transplantation were examined in the three groups.
Results: All 7 children in the group infused with TNC >10 x 10(7)/kg got a long-term stable engraftment. The median time of absolute neutrophil count >0.5 x 10(9)/L was 14.8 days (range 12-20 days) and platelets >50 x10(9)/L was 52.3 days (range 26-86 days). They survived in a disease-free state. Of the 9 children in the group infused with TNC between 10 x 10(7)/kg and 7 x 10(7)/kg, 7 got engraftment. The median time of absolute neutrophil count >0.5 x 10(9)/L was 16.4 days (range 11-30 days) and platelets >50 x 10(9)/L was 63.7 days (range 34-140 days). Four children got a long-term stable engraftment and survived in a disease-free state. Two children with beta-thalassemia major had secondary rejection after engraftment and autologous hematopoitic recovery. One child died after engraftment and one child died in the early period after transplantation. Of the 18 children in the group infused with TNC<7 x 10(7)/kg, 16 children got engraftment. The median time of absolute neutrophil count >0.5 x 10(9)/L was 19.5 days (range 10-29 days) and platelets >50 x 10(9)/L was 70.1 days (range 41-116 days). Eight children had a long-term stable engraftment and survived in a disease-free state. Two children with beta-thalassemia major had secondary rejection after engraftment and autologous hematopoitic recovery. Six children died after engraftment. Two children had graft failure.
Conclusions: TNC dose is an important influencing factor for hematopoietic stem cell engraftment in cord blood transplantation. An increased TNC dose may improve the success of cord blood transplantation.