Dermal fibroblast altering their actin gene expression (which is silenced in dermal fibroblasts). When dermal fibroblasts express actin, the cells can slowly contract. This contraction plays a critical role in wound healing and fibrosis. By pulling tissues closed differentiated myofibroblasts, seal the skin after an injury (thereby, preventing infection but inducing scar formation. Myofibroblasts can also be derived from non-fibroblast sources. Based on evidence of α-SMA expression from lung injuries, myofibroblasts can "arise de novo" directly from mesenchymal stem cells. Unlike other fibroblast cell types, dermal fibroblasts are far less likely to change into other cell types. For example, when a dermal
Cephalopod dermal structures Cephalopod dermal structures Cephalopods exhibit various dermal structures on their mantles and other parts. These may take the form of conspicuous warts, cushions, papillae or scales, though in many species they are microscopic tubercles. The most elaborate forms are found among the oceanic squid of the order Teuthida. Most cephalopod dermal structures take the form of tubercles, and these are the only cartilaginous dermal structures (the various "dermal cushions" being composed of other forms of connective tissue). All three main types of cartilage found in vertebrates are represented among the different squid species: hyaline, elastic and fibrocartilage. Tubercles of hyaline