Back to 2017 Annual Meeting Program
In-Vivo Survivability of Stem Cells After Peripheral Nerve Reconstruction Using Decellularized Nerve Allografts
Nadia Rbia, MD, MSC1; Liselotte F. Bulstra, BsC2; Allen T. Bishop, MD2; S.E.R. Hovius, MD; PhD3; Alexander Shin, MD2
1Erasmus Medical Center, Rotterdam, Netherlands, 2Clinic, Rochester, MN, 3Department of Plastic Surgery, Erasmus MC, Rotterdam, Netherlands
Objective: Successful repair of segmental peripheral nerve defects remains a clinical challenge. Processed nerve allografts have been used to bridge segmental nerve gaps. However, in large nerve defects, functional outcomes are not comparable to autograft reconstruction yet; the longer the nerve gap, the poorer the outcome. Nerve architecture and the extracellular matrix are preserved after processing, while all cellular material including Schwann cells and axons are removed. Therefore the addition of supporting cells has been proposed to improve the allograft. Adipose-Derived Mesenchymal Stem Cells (AMSC) can potentially provide the necessary support for nerve regeneration due to local production of essential growth factors. While the mechanisms underlying the neurotrophic potential of AMSC remains unknown, it is postulated that the remaining extracellular matrix (ECM) still has biological activity that influences the AMSC and their differentiation. Therefore, the purpose of this study was to 1) evaluate the in-vivo survivability of the AMSC after seeding in a rat sciatic nerve model, 2) quantitate the fate and differentiation potential of the cells and 3) evaluate the neurotrophic factors produced.
Method: A total of 27 rat nerve allografts were decellularized and seeded with autologous AMSC. Seeded allografts were implanted to reconstruct a 10-mm sciatic nerve defect and results were compared to autograft and allograft reconstruction. Prior to transplantation, cells were labelled with a lentiviral Luciferase vector to detect living cells by Bioluminescence imaging at different time points. To study the early regeneration, semi-quantitative RT-PCR was performed after 14 days in combination with gene specific assays for genes that are associated with nerve regeneration. To determine the fate of the implanted AMSC, immunohistochemical staining was obtained for the surface markers S100, PGP9.5, RECA-1, NGF and Luciferase.
Results: In-vivo Bioluminescence imaging showed a stem cell survival up to 31 days. Immunohistochemical stains and q-PCR results are currently being analyzed. Based on pilot data, we anticipate differences in growth factor levels released by the seeded allograft compared to the control groups.
Conclusion: This study demonstrates that it is feasible to seed AMSC's on a decellularized allograft and that the cells survive for a maximum period of 31 days after transplantation. Upon the seeding, secretion of neurotrophic and angiogenic factors are expected to be triggered. The combination of patient's own easily accessible, abundant supply of stem cells harvested from adipose tissue and the readily available processed nerve allograft is potentially a promising method for individualized peripheral nerve repair.
Back to 2017 Annual Meeting Program