Tiam Mana Saffari

213 MICRO CT ANALYSIS AFTER STEM CELL DELIVERY AND ANGIOGENESIS 10 INTRODUCTION The outcome of tissue transplantation critically depends on tissue revascularization 1 . Nerve trauma is often associated with extensive soft tissue damage, enhancing disability and impeding restoration of limb function 2 . In adult traumatic brachial plexus injuries, concomitant vascular injury portends a worse functional outcome following reconstruction 3 , emphasizing the role of vascularization in nerve reconstruction and subsequently nerve regeneration. A few studies suggest that revascularization patterns of allograft nerves after reconstruction is via proximal inosculation, a process of revascularization occurring primarily from proximal to distal 4,5 . Diminishing fibrosis and central necrosis in nerve grafts by early revascularization of the graft may enhance axonal regeneration, especially in larger diameter nerve grafts 4 . Surgical angiogenesis by a pedicled adipofascial flap is a potential strategy to improve the microcirculation and thus revascularization 6-8 . Stem cells offer several regenerative benefits to peripheral nerve regeneration, including secretion of trophic factors that promote angiogenesis, remyelination and a supportive microenvironment 9 . Adipose-derived mesenchymal stem cells (MSC) specifically are relatively easy to be isolated and are capable of differentiating into mesoderm lineages 9,10 . The combination of surgical angiogenesis and MSCs to allograft nerves may further improve neovascularization in allografts. Detailed three-dimensional (3D) evaluation of microvasculature is becoming a powerful tool to provide mechanistic understanding of angiomodulating strategies and could be applied to investigate this interaction in nerve allografts 11 . The purpose of this study was to evaluate the early microvascular architecture of nerve allografts enhanced with stem cell delivery and surgical angiogenesis in a rat sciatic nerve defect model.