Effect of testosterone and hypoxia on the expansion of umbilical cord blood [CD34.sup.+] cells in vitro

• Published in: Experimental and Therapeutic Medicine 2017, Vol.14 (5), p.4467
• Main Authors: Zhou, Liping, Zhang, Xiaowei, Zhou, Panpan, Li, Xue, Xu, Xuejing, Shi, Qing, Li, Dong, Ju, Xiuli
• Format: Report
• Language: English
• Subjects: Analysis; Genetic aspects; Health aspects; Hematopoietic stem cells; Hypoxia; Influence; Physiological aspects; Testosterone; Transplantation
• ISSN: 1792-0981
• DOI: 10.3892/etm.2017.5026

Successfully expanding hematopoietic stem cells (HSCs) is advantageous for clinical HSC transplantation. The present study investigated the influence of testosterone on the proliferation, antigen phenotype and expression of hematopoiesis-related genes in umbilical cord blood-derived cluster of differentiation (CD)[34.sup.+] cells under normoxic or hypoxia conditions. Cord blood (CB) [CD34.sup.+] cells were separated using magnetic activated cell sorting. A cytokine cocktail and feeder cells were used to stimulate the expansion of [CD34.sup.+] cells under normoxic (20% [O.sub.2]) and hypoxic (1% [O.sub.2]) conditions for 7 days and testosterone was added accordingly. Cells were identified using flow cytometry and reconstruction capacity was determined using a colony-forming unit (CFU) assay. The effects of oxygen concentration and testosterone on the expression of hematopoietic-related genes, including homeobox (HOX)A9, HOXB2, HOXB4, HOXC4 and BMI-1, were measured using reverse transcription-quantitative polymerase chain reaction. The results indicated that the number of CFUs and total cells in the testosterone group increased under normoxic and hypoxic conditions compared with the corresponding control groups. Furthermore, the presence of testosterone increased the number of CFU-erythroid colonies. In liquid culture, the growth of [CD34.sup.+] cells was rapid under normoxic conditions compared with under hypoxic conditions, however [CD34.sup.+] cells were maintained in an undifferentiated state under hypoxic conditions. The addition of testosterone under hypoxia promoted the differentiation of [CD34.sup.+] cells into [CD34.sup.+][CD38.sup.+][CD71.sup.+] erythroid progenitor cells. Furthermore, it was determined that the expression of hematopoietic-related genes was significantly increased (P