Cutaneous Scarring: Basic Science, Current Treatments, and Future Directions

Abstract

Significance: Scarring of the skin from burns, surgery, and injury constitutes a major burden on the healthcare system. Patients affected by major scars, particularly children, suffer from long-term functional and psychological problems. Recent Advances: Scarring in humans is the end result of the wound healing process, which has evolved to rapidly repair injuries. Wound healing and scar formation are well described on the cellular and molecular levels, but truly effective molecular or cell-based antiscarring treatments still do not exist. Recent discoveries have clarified the role of skin stem cells and fibroblasts in the regeneration of injuries and formation of scar. Critical Issues: It will be important to show that new advances in the stem cell and fibroblast biology of scarring can be translated into therapies that prevent and reduce scarring in humans without major side effects. Future Directions: Novel therapies involving the use of purified human cells as well as agents that target specific cells and modulate the immune response to injury are currently undergoing testing. In the basic science realm, researchers continue to refine our understanding of the role that particular cell types play in the development of scar. SCOPE AND SIGNIFICANCEThis review begins with an overview of how human skin wounds heal, with an emphasis on the formation of scar as the end result of wound healing. This is followed by a review of recent developments in the cellular biology of wound healing and scarring, particularly related to stem cells and fibroblasts. Finally, traditional and novel treatments intended to prevent and reduce scarring are described. This review will be of interest to clinicians and basic scientists who wish to better understand the processes of wound healing and scarring as well as the treatment options available. TRANSLATIONAL RELEVANCEA great deal has been learned about the cellular and molecular pathways that contribute to scar formation. At the same time, clinicians have understood for centuries that certain techniques allow wounds to heal faster with less scarring. Despite the enormity of the clinical problem presented by scarring, there has been a failure to translate the basic science of scarring into improved scarring treatments that take advantage of specific molecular and cellular targets. However, in the field, there is optimism that recent advances will bridge the gap between the basic science and the clinical treatment of scarring. CLINICAL RELEVANCE Scarring of the skin affects millions of patients and in some, particularly children and burn victims, causes a great deal of suffering. Scar prevention mainly consists of the principles of wound closure without tension and avoiding infection and wound breakdown. Various treatments for established scars exist, with varying levels of effectiveness. Burn scars are particularly challenging, and treatment is largely supportive with the option for revision surgery to remove scarred skin. A novel drug-based treatment that makes use of a specific mole...

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