Chronic wounds: pathological characteristics and their stem cell-based therapies

Chronic wounds are characterized by prolonged healing processes and poor prognoses, which have substantially impacted human health and daily life. Traditional treatment strategies have various limitations and drawbacks. Therefore, fully effective therapeutic approaches remain urgently needed. Stem cell (SC)-based therapies have drawn significant attention for their abilities of immunomodulation and pro-regeneration. It has been demonstrated that stem cells (SCs) can improve angiogenesis, collagen deposition, and hair rejuvenation, thus facilitating wound healing. In addition, attempts were performed to facilitate the cell survival, function, retention, and engraftment of the delivered SCs. In this review, we first introduce the pathological process involved in chronic wound healing. Following that, the mechanism of SCs in promoting chronic wound repair is discussed in detail. Then, we highlight recent SC-based therapies for chronic wound repair developments. Finally, we present our views on the remaining challenges and future trends of SC-based therapies for chronic wound treatment.