Isolation and characterization of neural crest-like progenitor cells in human umbilical cord blood

Introduction: Neural crest (NC)-like stem/progenitor cells provide an attractive cell source for regenerative medicine because of their multipotent property and ease of isolation from adult tissue. Although human umbilical cord blood (HUCB) is known to be a rich source of stem cells, the presence of the NC-like stem/progenitor cells in HUCB remains to be elucidated. In this study, we have isolated NC-like progenitor cells using an antibody to p75 neurotrophin receptor (p75NTR) and examined their phenotype and stem cell function in vitro. Methods: To confirm whether p75NTR⁺ NC-derived cells are present in cord blood, flow cytometric analysis of cord blood derived from P0-Cre/Floxed-EGFP reporter mouse embryos was performed. Freshly isolated HUCB mononuclear cells was subjected to flow cytometry to detect p75NTR⁺ cells and determined their immunophenotype. HUCB p75NTR⁺ cells were then collected by immunomagnetic separation and their immunophenotype, clonogenic potential, gene expression profile, and multilineage differentiation potential were examined. Results: NC-derived EGFP⁺ cells co-expressing p75NTR was detected in cord blood of P0-Cre/Floxed-EGFP reporter mice. We found that freshly isolated HUCB mononuclear cells contained 0.23% of p75NTR⁺ cells. Isolated p75NTR⁺ cells from HUCB efficiently formed neurospheres and could differentiate into neuronal and glial cell lineages. The p75NTR⁺ cells expressed a set of NC-associated genes and undifferentiated neural cell marker genes before and after the culture. Conclusions: These findings revealed that HUCB contained the p75NTR⁺ NC-like progenitor cell population which have the self-renewal capacity and the potential to differentiate into both neuronal and glial cell lineages.