Bioactive Materials Facilitating Targeted Local Modulation of Inflammation.

•Electrospun polycaprolactone surfaces were immobilized with a monolayer of the cytokine interleukin-4 to create a “bioactive” immunomodulatory surface capable of influencing the phenotype of macrophages responding to the material surface in vivo.•Bioactive surfaces, evaluated in vitro by using macrophage culture, exhibited upregulation of anti-inflammatory M2 genes and facilitated morphological changes consistent with macrophage activation.•As a subcutaneous implant in a 14-day model of acute inflammation, bioactive surfaces polarized macrophages from their M1 pro-inflammatory to M2 anti-inflammatory phenotypes, leading to a significant reduction in the local immune-driven foreign body response.•As vascular grafts in a 28-day mouse carotid interposition model, bioactive grafts maintained their macrophage polarization and immunomodulatory effects, significantly reducing adventitial encapsulation and neointimal hyperplasia development.