Figure 7.

Characteristics of human hypertrophic scars and keloids. (A) Hypertrophic scar: This appears as a red, raised scar that does not extend beyond the boundaries of the original injury. They have nodular collagen deposits containing α-SMA producing myofibroblasts that are involved in scar contracture. Hypertrophic scars can regress with time. The main findings from studies on the role of TGF-β signaling and hypertrophic scarring are indicated. (B) Keloid: This appears as a shiny and smooth protuberance ranging from pink to purple in color and extends beyond the boundaries of the original wound. Unlike hypertrophic scars, keloids do not have nodular collagen deposits, α-SMA-producing myofibroblast, do not undergo scar contracture, and do not regress with time. The main findings from studies on the role of TGF-β signaling and keloid formation are indicated. Images were obtained with permission from the DermNet NZ Web site (www.dermnetnz.org). To see this illustration in color, the reader is referred to the web version of this article at www.liebertpub.com/wound