Back to 2013 Annual Meeting Program
Restoration of Long Nerve Defects with Epineural Sheath Conduit Supported with Bone Marrow Stromal Cells in Sheep Model. A Preliminary Report
Maria Madajka, PhD; Can Ozturk, MD; Miroslaw Lukaszuk, MD; Jacek Szopinski, MD, PhD; Vlodek Siemionow, PhD; Maria Z. Siemionow, MD, PhD, DSc
Cleveland Clinic, Cleveland, OH, USA
Hypothesis: Nerve gaps that need conduit or allograft material tend to involve regional loss of overlying soft tissues and muscles spanning a gap of over 20 cm. The present standard of care for repair of nerve defects is autograft but in case of multiple injuries it becomes challenging. Nerve allografting requires supportive immunosuppression and demonstrated poor motor recovery. To address these needs we developed a new epineural sheath conduit supported with bone marrow stromal cells (BMSCs) to restore 6 cm nerve defects. We hypothesized that laminin rich and immunologically neutral epineural sheath filled with BMSCs can enhance neuronal growth. The use of BMSCs population will contribute to structural support and secretion of growth factors for enhancement of nerve regeneration.
Methods: Large animal - sheep model - was used since peripheral nerves are histologically and morphometrically similar to human nerves and long nerve defects can be created. Epineural sheath tube was created from the median nerve by the pull out technique, removing all fascicles. BMSCs were obtained from donor animal by flush method, purified by the buffy coat technique and cultured for 14 days. Next, cells were trypsinized, fluorescently labeled and injected into the empty epineural tube in the range of 5- 8 x 10 6 cells. Restoration of 6cm median nerve defect with epineural conduit was performed using microsurgical techniques. Twelve sheep median nerves were evaluated in six animals including: autograft controls (n=2), saline control without BMSCs (n=2), autologous and allogenic conduits (n=2 each) filled with BMSCs. At 3 and 6 months follow up, nerve conduction velocity (NCV) and somatosensory evoked potential (SSEP) measurements and nerve samples were taken for immunohistochemistry and electron microscopy assessment.
Results: All animals recovered from surgery without complications. Immunofluorescent staining at 3 months in saline filled conduit showed presence of fascicle-like structure in the proximal, middle, and distal parts of the conduit. Migratory potential of BMSCs in lymphoid organs was analyzed by fluorescent staining. No presence of BMSCs was detected in liver, lymph nodes, spleen and thymus 6 months after SCEC transplantation. The preliminary analysis of NCV and SSEP assessment data confirmed presence of neurosensory responses in both saline and BMSC-filled conduit groups.
Summary: We confirmed feasibility of using epineural sheath conduit to restore 6 cm nerve defects in sheep model. Preliminary results of immunohistochemical and neurosensory assessment confirmed regenerative properties of the epineural sheath conduit.
Back to 2013 Annual Meeting Program