Granzyme B in injury, inflammation, and repair

Fragile skin and susceptibility to skin tearing are major problems among the elderly and can be complicated further by impaired wound healing. Non-healing wounds fail to progress through the normal stages of healing and enter a state of chronic inflammation featuring increased proteolytic activity. Increased expression of the serine protease granzyme B is observed during prolonged inflammation and is implicated in the pathogenesis of several chronic inflammatory diseases. Although its role in cytotoxic lymphocyte-mediated apoptosis is well established, granzyme B can also degrade extracellular matrix proteins and alter inflammation if present in the extracellular milieu. The present review focuses on the emerging evidence for the involvement of granzyme B in chronic inflammation, impaired wound healing, and age-related skin fragility.