Figure 2.

Variables affecting the cutaneous immune microenvironment of wounds. Environmental impacts, such as skin moisture, ultraviolet (UV) exposure, timing of wounding and location of the wound, can all modulate immune responses to barrier disruption. Skin moisture levels can alter immune expression of antimicrobial proteins [76] as well as immune cell infiltration [79]. UV exposure can promote wound closure [84], as well as interferon signature [83]. Time of day can alter fibroblast activity in the wound [85], as well as immune cell trafficking [86]. The location of the wound on the body matters as well, as various immune cells differ in proportion throughout the body dependent on the location [80]. Finally, aging plays a major role in the microenvironment of wounds; aged skin is deficient in neutrophil and macrophage recruitment [87] and is also slower to re-epithelialize [88]. Figure created using Biorender.