Myofibroblast development is characterized by specific cell-cell adherens junctions.

Area of Science:

• Cell biology
• Wound healing research
• Biophysics

Background:

• Myofibroblasts in wound granulation tissue exhibit unique adherens junctions (AJs) compared to dermal fibroblasts.
• The precise function, molecular makeup, and formation mechanisms of myofibroblast AJs remain poorly understood.

Purpose of the Study:

• To investigate the role of cadherins in myofibroblast AJ formation and function during wound healing.
• To elucidate the contribution of alpha-smooth muscle actin (alpha-SMA) to the mechanical properties of myofibroblast AJs.

Main Methods:

• Analysis of cadherin expression (N-cadherin and OB-cadherin) in fibroblasts during wound healing and myofibroblast differentiation.
• Assessment of AJ structure and mechanical resistance in myofibroblast cell pairs using flow chamber assays.
• Evaluation of the impact of alpha-SMA inhibition and anti-cadherin peptides on myofibroblast contraction in collagen gels.

Main Results:

• Fibroblasts shift cadherin expression from N-cadherin in early wounds to OB-cadherin in contractile, alpha-SMA-positive myofibroblast-rich wounds.
• Myofibroblast AJs are reinforced by alpha-SMA-mediated contractility, conferring high mechanical resistance.
• Inhibition of alpha-SMA or OB-cadherin significantly reduces myofibroblast contractile activity and alters AJ morphology.

Conclusions:

• Cadherin expression dynamically changes during myofibroblast differentiation, with OB-cadherin becoming dominant in contractile myofibroblasts.
• Myofibroblast AJs, particularly those involving OB-cadherin, are essential for generating contractile forces during wound healing.