Building Stem Cell Treatments for Non-Healing Wounds
This review looks over progress in the use of stem cells treatments as a way to impact chronic inflammation and treat non-healing wounds:
A chronic wound develops when a wound fails to heal within an expected time frame and fails to achieve functional closure. There are many factors that impede healing, including co-morbid clinical conditions, aging, poor tissue perfusion, malnutrition, unrelieved pressure to the surface of the wound, immune suppression, malignancy, infection, obesity, and a number of medications. The usual patient with a nonhealing wound has a combination of several of the factors mentioned earlier, making any one therapeutic option unlikely to succeed.One common thread with almost all nonhealing wounds is a persistent inflammatory state. Macrophages, known to mediate inflammation, influence healing in a positive way through increasing angiogenesis, decreasing bacterial loads, phagocytosing debris, and providing matrix deposition. If, however, a persistent inflammatory state develops in which the macrophages are dysregulated and become skewed toward a type I inflammatory phenotype, impeding progress toward wound repair and regeneration. Another potential explanation for the nonhealing wound is the presence of intrinsically dysfunctional or senescent cells that are incapable of responding to normal biochemical signals.
A number of treatment modalities are currently used to accelerate wound healing. The use of stem cell therapy has been hypothesized as a potentially useful adjunct for nonhealing wounds. Specifically, mesenchymal stem cells (MSCs) have been shown to improve wound healing in several studies. Immune modulating properties of MSCs have made them attractive treatment options. MSCs may be more useful if they are preactivated with inflammatory cytokines such as tumor necrosis factor alpha or interferon gamma.