ABSTRACT
Object To study the effect of cryopreservation on the ability of hematopoietic stem cells from human bone marrow and the action of total saponins of Panax ginseng (TSPG) to reduce their freezing injury. Methods Gradual cooling methods were used to place mononuclear cells (MNC) in liquid nitrogen with 5% dimethylsulfoxide (DMSO) for 3—5 months. After thawed, the biological properties of MNC were monitored, which included the mean trypan blue exclusion rate and the mean recovery rate of MNC, CFU-Mix, CD34+ cell, and total cells; Thawed MNC were cultured with various concentrations of TSPG, the effect of TSPG on the recoverable ability from cryopreservation damage were detected by colony-forming assay, colorimetric MTT assay for cell proliferation and flow cytometry. Results A fraction of MNC lost their proliferatory ability after thawed, but the damage was not deteriorated with freezing time. TSPG (25 ?g/mL) could raise the colony production rate of thawed hematopoietic stem cells; TSPG (25—50 ?g/mL) could raise the colony production rate of thawed hematopoietic stem cells; TSPG (25—50 ?g/mL) could improve their proliferation; TSPG (25 ?g/mL) could also promote the entray of them into cell proliferatory cycle. Conclusion TSPG could induce the proliferation of thawed hemato- poietic stem cells and raise the post-freezing recoverable ability of hematopoietic stem cells.