Wound Healing by Keratinocytes: A Cytoskeletal Perspective

Skin, being the protective barrier against the environment, can be subject to frequent trauma and stress, hence has the ability to heal itself rapidly. This capacity is attributed to a large number of resident stem cells and progenitors in the skin, which are activated to proliferate, migrate and differentiate to recreate the cellular diversity and regain tissue integrity. The barrier function of the skin is maintained by the epidermis, a multilayered epithelial compartment formed of keratinocytes. Wound repair evokes the capacity of cells to sense and respond to environmental cues. Tissue damage demands rapid cellular action, wherein spatio-temporally regulated cellular responses are critical determinants of the outcome of healing. Hence cells surrounding the wound have to immediately sense the damage and must activate the key signaling pathways to launch the wound-healing response. Emerging data is indicating that mechanical tension release is one of the first cues sensed by the neighboring cells of the damage. This cue is relayed by the cytoskeleton and converted into biochemical and cellular signals, which help the cells to respond accordingly to the trauma. In this review, we will focus on the role of keratinocytes and keratinocyte stem cells in wound healing, and the cytoskeletal dynamics involved therein.