BACKGROUND: The Cord Blood Transplantation (COBLT) Study banking program was initiated in 1996. The study goals were to develop standard operating procedures for cord blood (CB) donor recruitment and banking and to build an ethnically diverse unrelated CB bank to support a transplantation protocol.

STUDY DESIGN AND METHODS: The hematopoietic progenitor cell (HPC) and lymphocyte subset (LS) content of approximately 8000 CB units were characterized, and these results were correlated with donor ethnicity, birth weight, gestational age, sex, and type of delivery.

RESULTS: There was a significant correlation of CD34+ cell count with colony‐forming unit (CFU)–granulocyte‐macrophage (r = 0.68, p < 0.001), CFU–granulocyte‐erythroid‐macrophage‐megakaryocyte (r = 0.52, p < 0.001), burst‐forming unit–erythroid (BFU‐E; r = 0.61, p < 0.001), and total CFUs (r = 0.67, p < 0.001). Nucleated red blood cell count was significantly correlated with total CD34+ (r = 0.56, p < 0.001), total CFU (r = 0.50, p < 0.001), BFU‐E (r = 0.48, p < 0.001), and counts of CD34+ subsets (p < 0.001). Caucasian ethnicity was significantly correlated with higher CD3+/CD4+, CD19+, and CD16+/CD56+ LSs. Furthermore, CD34+/CD38– and CD34+/CD61+ CB units (HPC‐C) were significantly lower in African American and Asian persons compared to Caucasian and Hispanic persons. Male sex was associated with significantly fewer CD3+/CD4+, CD19+, and CD16+/CD56+ but increased CD3+/CD8+ LSs (p < 0.001). Finally, cesarean section was associated with significantly higher total CFU and CD16+/CD56+ but lower CD3+/CD4+, CD3+/CD8+, and CD19+ LSs.

CONCLUSION: These results provide a standard and range for uniformly processed HPC‐C progenitor cells and LSs. CB progenitor cells and/or LSs may in the future predict for rapidity of engraftment, incidence of graft‐versus‐host disease, speed and quality of immunore‐ constitution, graft‐versus‐tumor effects, and/or success of gene transfection after CB transplantation.