Conventional therapeutic applications of mesenchymal stromal cells (MSCs) focus on cell replacement and differentiation; however, increasing evidence suggests that most of their therapeutic effects are carried out by their various secretions. This study investigated the application of conditioned medium (CM) from human umbilical cord blood-derived MSCs (hUCB-MSCs) to improve hair growth and developed a method to reliably produce this optimized CM. Primed MSC-derived CM (P-CM) with combinations of TGF-β1 and LiCl was optimized by comparing its effects on the cell viability of dermal papilla cells (DPCs). P-CM significantly increased the viability of DPCs compared to CM. The secretion of vascular endothelial growth factor (VEGF) in DPCs was regulated by the macrophage migration inhibitory factor (MIF) in the P-CM secreted by MSCs. These findings suggest that P-CM can improve the efficacy in hair growth via a paracrine mechanism and that MIF in P-CM exerts hair growth-promoting effects via a VEGF-related β-catenin and p-GSK-3β [SER9] signaling pathway. Furthermore, clinical trials have shown that 5% P-CM improved androgenetic alopecia through producing an increased hair density, thickness, and growth rate, suggesting that this topical agent may be a novel and effective treatment option for patients with androgenetic alopecia.

Umbilical cord blood (UCB) is used as a source of donor cells for hematopoietic stem cell (HSC) transplantation. The success of transplantation is dependent on the quality of cord blood (CB) units for maximizing the chance of engraftment. Improved outcomes following transplantation are associated with certain factors of cryopreserved CB units: total volume and total nucleated cell (TNC) count, mononuclear cell (MNC) count, and CD34+ cell count. The role of the storage period of CB units in determining the viability and counts of cells is less clear and is related to the quality of cryopreserved CB units. Herein, we demonstrate the recovery of viable TNCs and CD34+ cells, as well as the MNC viability in 20-year-old cryopreserved CB units in a CB bank (MEDIPOST Co., Ltd., Seongnam-si, Gyeonggi-do, Korea). In addition, cell populations in CB units were evaluated for future clinical applications. The stable recovery rate of the viability of cryopreserved CB that had been stored for up to 20 years suggested the possibility of uses of the long-term cryopreservation of CB units. Similar relationships were observed in the recovery of TNCs and CD34+ cells in units of cryopreserved and fresh CB. The high-viability recovery of long-term cryopreserved CB suggests that successful hematopoietic stem cell (HSC) transplantation and other clinical applications, which are suitable for treating incurable diseases, may be performed regardless of long-term storage.

Mesenchymal stem cells (MSCs) are one of the most extensively studied stem cell types owing to their capacity for differentiation into multiple lineages as well as their ability to secrete regenerative factors and modulate immune functions. However, issues remain regarding their further application for cell therapy. Here, to demonstrate the superiority of the improvement of MSCs, we divided umbilical cord blood-derived MSCs (UCB-MSCs) from 15 donors into two groups based on efficacy and revealed donor-dependent variations in the anti-inflammatory effect of MSCs on macrophages as well as their immunoregulatory effect on T cells. Through surface marker analyses (242 antibodies), we found that HLA-A2 was positively related to the anti-inflammatory and immunoregulatory function of MSCs. Additionally, HLA-A2 mRNA silencing in MSCs attenuated their therapeutic effects in vitro; namely, the suppression of LPS-stimulated macrophages and phytohemagglutinin-stimulated T cells. Moreover, HLA-A2 silencing in MSCs significantly decreased their therapeutic effects in a rat model of hyperoxic lung damage. The present study provides novel insights into the quality control of donor-derived MSCs for the treatment of inflammatory conditions and diseases.