Vancomycin-impregnated decellularized bovine pericardium membranes coating silicone implants: in-vivo biocompatibility and antibacterial efficacy in a rat model

Abstract

Purpose: To evaluate the inflammatory response, fibrotic encapsulation, tissue integration, and antibacterial effectiveness of silicone implants coated with decellularized bovine pericardium membranes, with or without vancomycin impregnation. Methods: Seventy-two Wistar rats received subcutaneous silicone implants and were allocated to six groups: uncoated silicone under aseptic conditions; uncoated silicone under infected conditions; silicone coated with decellularized bovine pericardium under aseptic conditions; silicone coated with decellularized bovine pericardium under infected conditions; silicone coated with vancomycin-impregnated pericardium under aseptic conditions; and silicone coated with vancomycin-impregnated pericardium under infected conditions. Infected groups were challenged with Staphylococcus aureus and evaluated at day 7. Aseptic groups were analyzed at 30, 60, and 180 days. Histological assessment included semi-quantitative scoring of inflammatory cells, fibroblasts, angiogenesis, implant infiltration, and resorption. Antibacterial activity was quantified by colony-forming unit counts. Data were analyzed using non-parametric statistics. Results: Vancomycin-impregnated pericardium coatings significantly reduced S. aureus colonization compared with uncoated and pericardium-only implants. At day 7, these coatings markedly attenuated neutrophil infiltration and acute inflammation. At 30 and 60 days, pericardium-coated implants exhibited lower fibroblast scores and enhanced implant infiltration compared with uncoated silicone. At 180 days, vancomycin-impregnated coatings consistently showed reduced fibrotic and inflammatory markers, despite reduced sample size. Conclusions: Decellularized bovine pericardium coatings modulate the host response to silicone implants, and vancomycin impregnation provides additional antibacterial and anti-inflammatory benefits without impairing tissue integration.