Tissue Engineered Soft Tissue Reconstruction Using Non-invasive Mechanical Preconditioning and a Shelf-ready Allograft Adipose Matrix

BACKGROUND:Adipose tissue defects leading to severe functional (disability) and morphological (disfigurement) morbidity are often treated in plastic surgery with fat grafting, which can be limited by resorption, necrosis, and cyst formation. Our study aimed to assess whether adipose scaffolds could provide an environment for in situ autologous fat grafting, and to study whether adipose cell migration and proliferation (adipogenesis) within scaffolds could be enhanced by preliminarily increasing the vascularity (preconditioning) of the surrounding tissues recipient of the scaffolds. METHODS:Using an established rodent model of subcutaneous tissue/scaffold grafting, we tested the potential of a human-derived, shelf-ready, injectable, decellularized allograft adipose matrix (AAM) to reconstruct soft tissue defects when used in combination with non-invasive mechanical (suction-induced) skin preconditioning. RESULTS:Combined use of the AAM and non-invasive skin preconditioning significantly improved long-term volume retention (50-80% higher at a 12-week follow-up) and histological quality of reconstructed tissues compared to standard of care (autologous adipose grafts). The components of the AAM supported adipogenesis and angiogenesis. Combining the AAM to living adipose grafts mitigated negative outcomes (lower long-term volume retention, higher presence of cystic-like areas). CONCLUSIONS:Our study suggests that the synergistic use of the AAM and non-invasive tissue preconditioning provides an effective solution to improve fat grafting. These strategies can easily be tested in clinical trials and could establish the basis for a novel therapeutic paradigm in reconstructive surgery.