BAP31 regulated polarization of macrophages through C/EBP β in cutaneous wound healing

The functions carried out by macrophages are essential in the processes of repairing skin injury. However, the mechanism of the M2 macrophage and its role in cutaneous wound healing remain elusive. B cell receptor associated protein 31 (BAP31) plays an important role in the immune system, and its function in connection with macrophages has yet to be determined. The present study demonstrates that the process of cutaneous wound healing slowed down in bone marrow-specific BAP31 knock down Lyz2-cre-BAP31 flox / flox mice. In addition, further studies show that various kinds of macrophage M2 polarization related factors were regulated by BAP31. Among these molecules C/EBP β was significantly affected. However, IL-4 but not IFN-γ, is able to recover the expression levels of C/EBP β and its downstream transcript factors induced by BAP31. Then, we demonstrated that BAP31 regulated macrophage M2 polarization by negative regulation of IL-4Rα and positive influence on Egr-2 to affect C/EBP β. Our findings reveal a novel mechanism of BAP31 in regulating M2 macrophage, and provide novel targets for the prevention and treatment of chronic wounds.