<< Back to the abstract archive
Translational Development of Injectable Allograft Adipose Matrix for Soft Tissue Filling: from Conception to Clinical study
Francesco M. Egro1, Lauren Kokai1, Benjamin Schilling1, Evangelia Chnari2, Yen-Chen Huang2, Emily Imming2, Kacey Marra1, J. Peter Rubin1
1. Department of Plastic Surgery, University of Pittsburgh
2. Musculoskeletal Transplant Foundation
2017-02-13
Presenter: Francesco M. Egro MD, MSc, MRCS
Affidavit:
Vu T. Nguyen
Director Name: Vu T. Nguyen
Author Category: Resident Plastic Surgery
Presentation Category: Basic Science Research
Abstract Category: General Reconstruction
INTRODUCTION: There is a clinical need for an off-the-shelf bioinductive soft-tissue replacement in reconstructive surgery. Our group developed injectable Allograft Adipose Matrix (AAM) as a solution, derived from cadaveric human subcutaneous adipose tissue through a decellularization and milling process. The final form is lyophilized powder rehydrated before use.
METHODS: After refining the processing, our preclinical testing studied cellular ingrowth, vasculogenesis, adipogenesis and volume retention in vitro, and in both immunocompromised and wild type rodent models. We then implemented a prospective clinical study.
RESULTS: In vitro seeding of ASCs on AAM, showed attachment and proliferation of ASCs for 3 days, followed by production of new matrix within 7 days and changes to adipocyte morphology. AAM injected on the dorsum of immunocompromised nude mice supported adipogenesis at 6 weeks, with progressive increase in adipocyte frequency at 12-24 weeks and graft retention of 44±16% at 24 weeks. AAM injected in the dorsal flanks of immunocompetent Fisher rats showed higher graft retention (89±16%) up to 3 weeks, and induction of anti-inflammatory M2a macrophages as early as 72 hours compared to controls and alternative ECM derived products. The 16-week prospective clinical study evaluated subcutaneous AAM injection of the dorsal wrist of 15 patients, showing a graft retention of 47.14% at 16 weeks, with no histological evidence of inflammation or necrosis and no adverse events.
CONCLUSIONS: AAM is a novel off-the-shelf adipose-derived injectable matrix, which represents a safe alternative for soft-tissue reconstruction. Bio-inductive AAM shows favorable volume retention, cellular infiltration, and de-novo adipogenesis from endogenous precursor cells.
