Vascularization Strategies for Peripheral Nerve Tissue Engineering

Abstract

Vascularization plays a significant role in treating nerve injury, especially to avoid the central necrosis observed in nerve grafts for large and long nerve defects. It is known that sufficient vascularization can sustain cell survival and maintain cell integration within tissue‐engineered constructs. Several studies have also shown that vascularization affects nerve regeneration. Motivated by these studies, vascularized nerve grafts have been developed using various different techniques, although donor site morbidity and limited nerve supply remain significant drawbacks. Tissue engineering provides an exciting alternative approach to prefabricate vascularized nerve constructs which could overcome the limitations of grafts. In this review article, we focus on the role of vascularization in nerve regeneration, discussing various approaches to generate vascularized nerve constructs and the contribution of tissue engineering and mathematical modeling to aid in developing vascularized engineered nerve constructs, illustrating these aspects with examples from our research experience. Anat Rec, 301:1657–1667, 2018. © 2018 The Authors. The Anatomical Record published by Wiley Periodicals, Inc. on behalf of American Association of Anatomists.

The Superficial Inferior Epigastric Artery Fascia Flap in Rats

“…32 A lack of blood supply could lead to nerve hypoxia and damage, leading to nerve fibrosis. 33,34 At time of a nerve injury, Wallerian degeneration is activated causing Schwann cell proliferation distal to the nerve injury. 35,36 This process causes blood vessels to precede Schwann cell migration and to stimulate axonal extension, describing an important interaction between Schwann cells and blood vessels.…”

Advances in the Ongoing Battle against the Consequences of Peripheral Nerve Injuries

“…Autologous harvesting is the best way to avoid an immune reject or reaction. In the review by Muangsanit et al in the present Thematic Papers issue (Muangsanit et al, ), the authors have discussed about how the key topics in vascularization for nerve regeneration (Best and Mackinnon, ; el‐Barrany et al, ) affect the generation of vascularized nerve grafts, vascularized grafts by vascular implantation, blood vessel‐included tabulation, and biogenic vascularized nerve conduits. Muangsanit et al also discuss the most recent advances and approaches trying to solve whether engineering vascular structures within scaffolds may improve nerve repair construct design, a very interesting and promising hypothesis (Jain et al, ).…”

“…Recently the growing use of fibrin instead of or jointly with sutures have also begun to render additional benefits to prevent scar tissue. In the present volume of The Anatomical Record, Muangsanit et al and Muratori et al present literature and data on the role of vascularization and VEGF family molecules on nerve regeneration (Muangsanit et al, ; Muratori et al, ), while Wang et al, () report comparisons between different sutureless repair strategies, with or without using fibrin conduits.…”

Polycaprolactone Electrospun Fiber Mats Prepared Using Benign Solvents: Blending with Copper(II)‐Chitosan Increases the Secretion of Vascular Endothelial Growth Factor in a Bone Marrow Stromal Cell Line

“…Established technologies are not yet effective in vascularizing newly formed tissues, both soft and hard, and the lack of vessels often results in accumulation of metabolites and degradation products, formation of fibrotic tissue, and even necrosis 5. Emerging technologies have shown promising results in terms of effective control of angiogenesis during the regeneration of various targeted tissues (e.g., skin, cardiac tissue, nerves),6–8 suggesting that their application could increase both the size of the treated defect and the rate of tissue regeneration 9. For example, the effective control of angiogenesis could be important for the fabrication of small vessel grafts (inner diameter <6 mm) 10.…”