Natural killer cells in wound healing

Physiologic wound healing is a complex and highly coordinated biological process, in which a number of different cell types participate in a tightly orchestrated manner to repair the damaged tissue.Wound healing is divided into three major phases of hemostasis and inflammation, re-epithelialization and granulation tissue formation, and tissue remodelling. In general, the role of the immune system in wound repair is not restricted to combating the microbe invasion at the site of injury, but it also participates in the removal of the damaged tissue and contributes to the healing process. It is evident, that natural killer (NK) cells regulate the early onset and resolution of the inflammatory phase in wound repair and may also contribute to other crucial events in the normal wound healing process, as in re-epithelialization, angiogenesis, granulation tissue formation, and remodelling. Epithelium lines the entire human body and protects the internal organs from contact with the outside environment. The injuries of the epithelial tissues are promptly repaired, resulting in integration of new tissue into the surrounding intact tissue. In general, wound healing in different epithelial tissues occurs in a similar manner in spite of the differences in their physical and chemical environment. The immune system in wound repair combats the microbe invasion at the site of tissue injury, and it also participates in the removal of the damaged tissue and contributes to the process of healing. It is evident that NK cells regulate the early onset and resolution of the inflammatory phase in wound repair.