Method of RBC Depletion from Human Umbilical Cord Blood

Lyu, Chuhl Joo; Park, Song Hee; Cho, Hyun Sang; Kim, Hyun Ok; Lim, Jong Baeck; Park, Sae Myung; Yang, Chang Hyun; Kim, Kir Young; Cho, Jae Sung; Park, Yong Won

Abstract

BACKGROUND: Cord blood(CB) has been suggested as an alternate source of stem cells in transplantation because of lower incidence of graft versus host disease and ease of collection. To optimize storage space cord blood needs to be stored as separated product. Additionally, for cord blood bank to be economical and efficient, volumes smaller than that of whole packs needs to be stored. However, CB processing procedures described so far involve open systems and/or reagents which are not licensed for use in humans. Consequently, these procedures poorly match the needs for closed-system, large-scale CB banking. In our study, we use the triple bag system in which the CB is separated by centrifugation to maintain of sterility and volume reduction. And simple and effective RBC depletion method was evaluated with 10% pentastarch and 4% modified gelatin.
METHODS
The collection of CB was performed from 45 full term newborns. The collection was made by gravity and uterine contraction before placental expulsion with triple transfusion bag containing CPD-A1. 10% Pentastarch(Group A) or 4% modified gelatin(Group B) is added directly to the CB containing bag. After RBC sedimentation, the WBC-rich supernatant is collected in a satellite bag. After RBC depletion, recovery of mononuclear cells(MNC), CD34+ cells were compared between two groups.
RESULTS
Mean volume of collected CB and final RBC-depleted products were 68.1+/-17.0 mL and 18.1+/-4.1 mL in Group A and 68.0+/-15.8 mL, 23.1+/-6.3 mL in Group B, respectively. After RBC depletion, the number of MNC and CD 34+ cells were 2.61+/-1.51x108, 1.19+/-0.96x106 in Group A and 4.03+/-3.16x108, 1.43+/-0.86x106 in Group B. Mean recovery of MNC, CD34+ cells were 70.2+/-43.7%, 60.2+/-31.5% in Group A, and 84.7+/-39.9% and 87.7+/-7.5% in Group B, respectively.
CONCLUSION
CB processing in closed-system using triple bag with 4% modified gelatin appears to be safe, easy, effective and particularly suitable for large-scale CB banking.