Methacrylic Acid Copolymer Coating Enhances Constructive Remodeling of Polypropylene Mesh by Increasing the Vascular Response

This study reports that a methacrylic acid (MAA)-based copolymer coating generates constructive remodeling of polypropylene (PP) surgical mesh in a subcutaneous model. This coating is non-bioresorbable and follows the architecture of the mesh without impeding connective tissue integration. Following implantation, the tissue response is biased toward vascularization instead of fibrosis. The vessel density around the MAA mesh is double that of the uncoated mesh two weeks after implantation. This initial vasculature regresses after two weeks while mature vessels remain, suggesting an enhanced healing response. Concurrently, the MAA coating alters the foreign body response to the mesh. Fewer infiltrating cells, macrophages, and foreign body giant cells are found at the tissue-material interface three weeks after implantation. The coating also dampens inflammation, with lower expression levels of pro-inflammatory and fibrogenic signals (e.g., Tgf-β1, Tnf-α, and Il1-β) and similar expression levels of anti-inflammatory cytokines (e.g., Il10 and Il6) compared to the uncoated mesh. Contrary to other coatings that aim to mitigate the foreign body response to PP mesh, a MAA coating does not require the addition of any biological agents to have an effect, making the coated mesh an attractive candidate for soft tissue repair.