Defining Parameters That Can Guide Public Cord Blood Units (CBUs) in Korea
Authors: Lee Junglim , Kim Byung-Su , Jang Soon- Hi , KIM Tai-Gyu 
Published: October 2019

Abstract
Background: It is well known that Total Nucleated Cell (TNC) and CD34 are the greatest limiting factor in the use of umbilical cord blood (UCB) for transplantation. To enhance high UCB quality, it is important that how the factors will affect the UCB. This study is to identify maternal, neonatal, obstetric factors that influence the suitability for banking and transplantation of UCB units collection.
Study design and methods: This study examined 6534 UCB (3712 at the Catholic Hematopoietic Stem Cell Bank and 2822 at the Daegu Fatima Hospital Public Umbilical Cord Bank) collected at two banks from October 2003 to June 2015. The variables were collected from retrospective records at the time of donation. The associations between TNC, CD34+ and variables including maternal age (MA), gestational age (GA), fetal body weight (FBW), time from collection to processing (T), collecting volume (CV), preTNC, and delivery type were analyzed by logistic regression.
Results: In our study cohort (n=6534, male 2988, female 2991, unkown 555, all Koreans), the median values of TNC, numbers of CD34+, MA, GA, FBW, T, preTNC, and CV were 9.24úI108/unit (range, 3.02-35.64), 2.0úI106/unit(range, 0.04-29.2), 31.0 years(range, 15-46), 277 days (range, 202-382), 3330g (range, 1740-4970), 19 hours (range, 1-54), 11.69úI108/unit (range, 3.41-50.32), and 83.5ml (range, 26.0-218.2) respectively.
In univariate analysis, variables that were associated with high TNC (defined as a TNC of > 9.24úI108/unit) included GA (defined as GA > 277 days) [OR 1.29 (95% CI 1.16-1.42 p < 0.001)], FBW (defined as FBW > 3330g) [OR 1.52 (95% CI 1.37-1.68 p < 0.001)])], CV (defined as > 83.5mL) [OR 2.61 (95% CI 2.36-2.88 p < 0.001)], preTNC [OR 25.45 (95% CI 22.34-29.00 p < 0.001)], and T (defined as T> 19 hours) [OR 0.87 (95% CI 0.79-0.96 p < 0.005)]. Variables that were associated with high CD34+ (defined as a number of CD34+ > 2.0úI106/unit) included MA (defined as MA > 31.0 years) [OR 0.90 (95% CI 0.82-0.99 P=0.036)], GA [OR 0.74 (95% CI 0.67-0.82 p < 0.001)], FBW [OR 1.41 (95% CI 1.27-1.56 p<0.001)], preTNC [OR 3.38 95% CI 3.06-3.74 p < 0.001]], and CV [OR 1.41 (95% CI 1.28-1.60 p<0.001)]
In multivariate analysis of TNC, preTNC [OR 20.71 (95% CI 17.87-24.00) p < 0.001]] was the best predictor of followed by normal delivery [OR 1.77 (95% CI 1.48-2.11 P<0.001)], FBW [OR 1.35 (95% CI 1.17-1.56 p<0.001)], CV [OR 1.31 (95% CI 1.13-1.53 p<0.001)], and female gender [OR 1.21 (95% CI 1.05-1.39 p=0.01)]. In multivariate analysis of CD34, was preTNC [OR 3.39 (95% CI 3.00-3.83 p < 0.001)] was the best predictor of followed by FBW [OR 1.41 (95% CI 1.25-1.58 P<0.001)], GA [OR 0.59 (95% CI 0.52-0.66 p<0.001)], MA [OR 0.84 (95% CI 0.75-0.94 p=0.003)], and female gender [OR 0.89 (95% CI 0.78-0.98 p=0.02)].
Conclusions: We established referential values of cord blood using large scaled CB units in Korea. In multivariate analysis, maternal/donor characteristics were associated with preTNC, FBW, and gender for both high TNC and CD34+. Our results confirm that is similar values to those reported in previous data. These associations could be used to prioritize donations, collections, optimizing resource utilization and financial modeling in Korean cord blood banks. We are focusing on collection education using the standard operation procedure to facilitate of high cells as well as on more recruits of healthy mothers.

Disclosures
No relevant conflicts of interest to declare.