Phenotypical determinants of stem cell subpopulations derived from human umbilical cord blood.

Abstract

Introduction. Human umbilical cord blood (HUCB) is a common source of hematopoietic progenitor cells; however, coexpression of CD34, CD38 and HLA DR antigens and of embryonic antigens (SSEA-4 and CD13) have not been described in HUCB.
Objective. The current study attempted to identify in HUCB the presence of these antigens.
Materials And Methods. Cord blood samples were obtained from 80 women with normal pregnancies, who were attending the gynecology-obstetrics service of the San Ignacio Hospital, Bogotá (Colombia). The antigens were identified with a FACS Calibur BDO flow cytometer and a cocktail of monoclonal antibodies.
Results. The population of CD34+ cells in HUCB was higher than 0.2% (p = 0.001). The levels of additional cell subpopulations were as follows: CD34+/CD38-/HLA-DR--0.015%-0.023%, CD34+/CD38+/HLA-DR--0.019%-0.30%, CD34+/CD38-/HLA-DR(+)--0.043%-0.068% and CD34+/CD38+/HLA-DR--0.24%-0.51%. Eight samples of the eighty were positive for embryonic markers. The most frequent phenotype in HUCB was CD34+ CD38+ HLA DR+.
Conclusion. This is the first time that SSEA-4 and CD13 antigens have been reported in human umbilical cord blood cells.