Using Stem Cells to Promote Wound Healing: An Emerging Solution for a Clinical Problem

Wound healing is a multi-faceted and tightly regulated process by which tissues and cells both proximal and distal to the site of injury collaborate to bring about effective closure and a restoration of normal tissue function. The roles of various cellular populations in the healing process often vary with the location and nature of the injury. Defects that result in ineffective or impaired wound closure/healing can have significant and deleterious effects on both the short and long-term health of the individual. Chronic slow healing or non-healing wounds represent a significant cause of morbidity, mortality and costs. Treatment and management options for these types of difficult-to-heal wounds are limited; however there is a growing interest in the use of stem cell based treatment strategies. In addition to giving rise to specialized healthy new tissue, the intrinsic trophic and paracrine actions, anti-inflammatory, and immunomodulatory properties of these cells have been shown to facilitate the recruitment and mobilization of endogenous progenitor cells, to promote tissue regeneration and to attenuate dysregulated cellular and humoral immune-mediated responses within various inflammatory niches. In recent years, both pre-clinical animal models as well as clinical studies have shown promising results for the development of new and effective treatment strategies using a variety of non-embryonic or adult tissue-derived stem/progenitor cell populations. In this chapter we review the in vivo role of stem cells and the stem cell niche during the wound healing process, so as to provide a context for potential exogenous stem cell therapeutic applications, as well as explore some of the recent evidence that supports improved healing and tissue regeneration.