Human stem-progenitor cells from neonatal cord blood have greater hematopoietic expansion capacity than those from mobilized adult blood.
OBJECTIVE
In this study we compared the hematopoietic capacity of CD34+ cell preparations from neonatal cord blood (CB) vs adult mobilized peripheral blood (PBSC) before and after ex vivo culture.


METHODS
CD34+ cell preparations purified from CB or PBSC were cultured in serum-free medium containing FKT: FLT-3 ligand (FL), KIT ligand (KL), and thrombopoietin (TPO).


RESULTS
After 1-4 weeks ex vivo culture, CB CD34+ cell preparations had greatly increased numbers of total cells, CD34+ cells, and colony-forming cells (CFC). In contrast, ex vivo-cultured PBSC CD34+ cell preparations generated far less in vitro assessed hematopoietic capacity. Nonobese diabetic severe combined immunodeficient mouse (NOD/SCID) engrafting potential (SEP) was maintained in ex vivo-cultured CB CD34+ cell preparations, whereas ex vivo-cultured PBSC lost SEP. CB CD34+ cells continued to proliferate throughout 3 weeks ex vivo, whereas after 1 week, no additional cell divisions were detected in PBSC CD34+ cells. After 3 weeks in culture, the average CB CD34+ cell had divided more than 5 times, as compared to only 2 times for the average PBSC CD34+ cell.


CONCLUSIONS
CB CD34+ cell preparations generated massively increased in vitro assessed hematopoietic capacity and maintained SEP during 1- to 4-week ex vivo cultures. In contrast, ex vivo-cultured PBSC CD34+ cell preparations generated far less in vitro assessed hematopoietic capacity and decreased SEP. The differences in the in vitro proliferative indices of membrane dye-labeled CD34+ cells from CB vs PBSC correlated with these functional differences.
Tanavde
Vivek M
VM
Department of Oncology, Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
Malehorn
Matthew T
MT
Lumkul
Rachata
R
Gao
Zhigang
Z
Wingard
John
J
Garrett
Elizabeth S
ES
Civin
Curt I
CI
D000328:Adult; D000818:Animals; D018952:Antigens, CD34 / Q000032:analysis; D015415:Biomarkers; D001773:Blood Cells / Q000166:cytology* / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D019070:Cell Lineage; D002469:Cell Separation; D002470:Cell Survival; D002478:Cells, Cultured / Q000166:cytology / Q000187:drug effects; D003114:Colony-Forming Units Assay; D016895:Culture Media, Serum-Free / Q000494:pharmacology; D005312:Fetal Blood / Q000166:cytology*; D005434:Flow Cytometry; D019650:Hematopoietic Stem Cell Mobilization; D018380:Hematopoietic Stem Cell Transplantation; D006412:Hematopoietic Stem Cells / Q000166:cytology* / Q000187:drug effects; D006801:Humans; D007231:Infant, Newborn; D008565:Membrane Proteins / Q000494:pharmacology; D051379:Mice; D016688:Mice, Inbred NOD; D016513:Mice, SCID; D013047:Specific Pathogen-Free Organisms; D019089:Stem Cell Factor / Q000494:pharmacology; D013926:Thrombopoietin / Q000494:pharmacology; D014183:Transplantation, Heterologous
D018952:Antigens, CD34; D015415:Biomarkers; D016895:Culture Media, Serum-Free; D008565:Membrane Proteins; D019089:Stem Cell Factor; C084881:flt3 ligand protein; D013926:Thrombopoietin