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 "Lepidoteuthis grimaldii" are actually dermal cushions with a vacuolate internal structure that are continuous with a similarly vacuolate underlying layer of mantle tissue. Ammonium ions (NH) are present in the mantle of this species at a measured concentration of 172 mM. Structurally very similar (though non-overlapping) dermal cushions are found in "Pholidoteuthis adami". It has been proposed that these two species achieve buoyancy by means of the fluid stored in their vacuolate dermal cushions and upper mantle layer. Given their spongy form, these cushions may also play a secondary protective role. The complex dermal structures of "Pholidoteuthis massyae" may play