Objective: The purpose was to compare two different ways of culturing hair follicle bulge stem cell: The defined keratinocyte-serum free medium (DK-SFM) method and the 3T3 feeder cell method.
Methods: The morphological features of cultured bulge stem cells were investigated by inverted phase control microscopy. Immunostaining of stem cell marker cluster of differentiation 34 (CD34) and epithelial cell marker cytokeratin 19 (CK19) were performed to identify the bulge stem cell. The stemness of bulge stem cells was evaluated by colony forming efficiency (CFE) and proportion of CD34 positive cells by flow cytometry.
Results: Hair follicle bulge stem cells could be successfully cultivated in vitro using two methods. They were both positive for CK19 and CD34. The colony forming efficiency of hair follicle stem cell cultured in DK-SFM and the 3T3 feeder cell was 69.4% and 62.2%, respectively. There was no significant difference in colony forming efficiency between these two methods (P > 0.05), while the CD34 positive cells proportion was higher in DK-SFM as 72.3% than the other as 34.7% (P < 0.05).
Conclusion: Two methods are applicable to culture bulge stem cells in vitro. The 3T3 feeder cell method is complicated and can propagate a lot bulge stem cells from hair follicle, while the DK-SFM method is easier to get pure bulge stem cell.