The Pro-reparative Engine: Stem Cells Aid Healing by Dampening Inflammation
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Purpose of Review
Stem cells have been proposed as sources for tissue replacement when healing does not occur. These cells could contribute directly to skin structures via differentiation, or via producing trophic factors that would ‘educate’ the microenvironment to encourage tissue repair. Studies in animals have supported both mechanisms, but translation to humans has been challenged by poor cell survival after transplantation. However, the improvement noted with even transient existence suggests another new possibility, that of suppressing the inflammatory response that limits regenerative healing. Herein, we will propose that this immunomodulatory aspect holds promise for promoting skin healing.
We have found that stem cell transplantation into wounds can dampen both acute and chronic inflammation, leading to more regenerative-like healing and diminished scarring.
Wound healing could be improved by dampening inflammation both initially to allow for tissue replacement to proceed and late to reduce scarring.
KeywordsMultipotential stromal cells/mesenchymal stem cells Inflammation Wound healing Wound matrix Immunomodulation
We thank the members of the Wells laboratory for helpful discussions and suggestions.
This work was supported by grants from the National Institute of General Medical Sciences (NIH, USA) (GM063569 and GM069668). A.B. is supported on a NIH T32 CATER fellowship (EB001026).
Compliance with Ethical Standards
Conflict of Interest
Andrew Bradshaw and Kyle Sylakowski declare that they have no conflict of interest.
Dr. Wells has a patent Owned by the University of Pittsburgh, pending; this patent is not licensed.
Human and Animal Rights and Informed Consent
This article does not contain any studies with human or animal subjects performed by any of the authors.
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