The Development of a Xenograft-Derived Scaffold for Tendon and Ligament Reconstruction Using a Decellularization and Oxidation Protocol

Abstract

To evaluate the biological, immunological, and biomechanical properties of a scaffold derived by architectural modification of a fresh-frozen porcine patella tendon using a decellularization protocol that combines physical, chemical, and enzymatic modalities. Porcine patellar tendons were processed using a decellularization and oxidation protocol that combines physical, chemical, and enzymatic modalities. Scaffolds (n= 88) were compared with native tendons (n= 70) using histologic, structural (scanning electron microscopy, porosimetry, and tensile testing), biochemical (mass spectrometry, peracetic acid reduction, DNA quantification, alpha-galactosidase [α-gal] content), as well as invitro immunologic (cytocompatibility, cytokine induction) and invivo immunologic nonhuman primate analyses. A decrease in cellularity based on histology and a significant decrease in DNA content were observed in the scaffolds compared with the native tendon (P < .001). Porosity and pore size were increased significantly (P < .001). Scaffolds were cytocompatible invitro. There was no difference between native tendons and scaffolds when comparing ultimate tensile load, stiffness, and elastic modulus. The α-gal xenoantigen level was significantly lower in the decellularized scaffold group compared with fresh-frozen, nondecellularized tissue (P < .001). The invivo immunological response to implanted scaffolds measured by tumor necrosis factor-α and interleukin-6 levels was significantly (P < .001) reduced compared with untreated controls invitro. These results were confirmed by an attenuated response to scaffolds invivo after implantation in a nonhuman primate model. Porcine tendon was processed via a method of decellularization and oxidation to produce a scaffold that possessed significantly less inflammatory potential than a native tendon, was biocompatible invitro, of increased porosity, and with significantly reduced amounts of α-gal epitope while retaining tensile properties. Porcine-derived scaffolds may provide a readily available source of material for musculoskeletal reconstruction and repair while eliminating concerns regarding disease transmission and the morbidity of autologous harvest.