Short-term in vivo biological and mechanical remodeling of porcine acellular dermal matrices

The purpose of this study was to assess the biological revitalization and mechanical integrity of Strattice(™) Reconstructive Tissue Matrix, a porcine-derived acellular dermal matrix, in vivo over time. We expanded the traditional subcutaneous model to incorporate biologic matrix scaffolds large enough to allow evaluation of mechanical properties in addition to the assessment of histological changes. Hematoxylin and eosin histology staining was used to evaluate cellular and tissue changes, and a mechanical testing frame was used to measure the ultimate tensile stress and Young's modulus of the implanted material over time. Cell infiltration and blood vessel formation into the porcine-derived acellular dermal matrix were evident at 2 weeks and increased with implantation time. Mechanical remodeling resulted in an initial decrease in ultimate tensile stress, not associated with cell infiltration, followed by a significant increase in material strength, concurrent with histological evidence of new collagen synthesis. Young's modulus followed a similar trend.