The αvβ6 integrin plays a role in compromised epidermal wound healing

The alpha v beta 6 integrin is an exclusively epithelial integrin that is highly expressed during fetal development. In adult tissue, alpha v beta 6 integrin is expressed during inflammation, carcinogenesis, and in wound healing. We previously reported that alpha v beta 6 integrin is highly expressed in poorly healing human wounds and its over-expression is associated with chronic wounds in a mouse model. The objective of this study was to investigate the role of alpha v beta 6 integrin in compromised wound healing induced by hydrocortisone treatment or aging by using young and old mice deficient in or overexpressing the beta 6 integrin subunit in the epidermis. Untreated aged beta 6 integrin-deficient (beta 6-/-) animals showed a significant delay in wound healing when compared to their age-matched controls or younger beta 6-/- mice. The most significant delay was observed at the stages where granulation tissue deposition was occurring. Hydrocortisone treatment significantly delayed wound healing in wild-type and beta 6 integrin-deficient mice in comparison with the untreated controls. However, hydrocortisone treatment in beta 6 integrin overexpressing animals did not cause a significant delay in wound healing. The results of this study suggest that alpha v beta 6 integrin plays an important role in wound healing in animals compromised by either age or stress mimicked by hydrocortisone.