Transforming Growth Factor Beta 3-Loaded Decellularized Equine Tendon Matrix for Orthopedic Tissue Engineering

Transforming growth factor beta 3 (TGF beta 3) promotes tenogenic differentiation and may enhance tendon regeneration in vivo. This study aimed to apply TGF beta 3 absorbed in decellularized equine superficial digital flexor tendon scaffolds, and to investigate the bioactivity of scaffold-associated TGF beta 3 in an in vitro model. TGF beta 3 could effectively be loaded onto tendon scaffolds so that at least 88% of the applied TGF beta 3 were not detected in the rinsing fluid of the TGF beta 3-loaded scaffolds. Equine adipose tissue-derived multipotent mesenchymal stromal cells (MSC) were then seeded on scaffolds loaded with 300 ng TGF beta 3 to assess its bioactivity. Both scaffold-associated TGF beta 3 and TGF beta 3 dissolved in the cell culture medium, the latter serving as control group, promoted elongation of cell shapes and scaffold contraction (p < 0.05). Furthermore, scaffold-associated and dissolved TGF beta 3 affected MSC musculoskeletal gene expression in a similar manner, with an upregulation of tenascin c and downregulation of other matrix molecules, most markedly decorin (p < 0.05). These results demonstrate that the bioactivity of scaffold-associated TGF beta 3 is preserved, thus TGF beta 3 application via absorption in decellularized tendon scaffolds is a feasible approach.