Determinación fenotípica de subpoblaciones de células madre derivadas de sangre de cordón umbilical.

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.