Matrix remodeling by MMPs during wound repair

• We discuss how specific MMPs act on ECM during two critical repair processes: re-epithelialization and resolution of scar tissue.
• For re-epithelialization, we discuss how MMP1 in skin and MMP7 in mucosal epithelia facilitate wound closure by cleaving different ECM or ECM-associated proteins to lessen integrin:matrix adhesion.
• For scars and fibrotic tissues, we discuss that a variety of MMPs carry out a diverse range of activities that can either promote or limit ECM deposition.
• However, few of these MMP-driven activities have been demonstrated to be due to a direct action on ECM.

Repair following injury involves a range of processes – such as re-epithelialization, scar formation, angiogenesis, inflammation, and more – that function, often together, to restore tissue architecture. MMPs carry out diverse roles in all of these activities. In this article, we discuss how specific MMPs act on ECM during two critical repair processes: re-epithelialization and resolution of scar tissue. For wound closure, we discuss how two MMPs – MMP1 in human epidermis and MMP7 in mucosal epithelia – facilitate re-epithelialization by cleaving different ECM or ECM-associated proteins to affect similar integrin:matrix adhesion. In scars and fibrotic tissues, we discuss that a variety of MMPs carry out a diverse range of activities that can either promote or limit ECM deposition. However, few of these MMP-driven activities have been demonstrated to be due a direct action on ECM.