Three‐dimensional configuration of orientated fibers as guidance structures for cell migration and axonal growth

Abstract

Peripheral nerve injuries can be surgically repaired by suturing the transected nerve stumps or, in case of larger lesions, by the transplantation of an autologous nerve graft. To avoid donor site morbidity, the development of artificial implants is desired. Clinically, hollow conduits have been used for this purpose but are inferior to the autograft because they lack internal guidance cues for Schwann cells and regenerating axons. In this article, we describe the design of a three-dimensional (3D) scaffold consisting of parallel fibers embedded in a collagen matrix. For this purpose, an electrospinning device was developed to produce and manipulate a 3D array of aligned poly(ɛ-caprolactone) (PCL) microfibers. This fiber array was then incorporated into biodegradable PCL tubes to serve as artificial nerve bridges. Using primary cultures of embryonic chicken dorsal root ganglia, we show that PCL microfibers in the 3D matrix of our composite scaffold guide the direction of Schwann cell migration and axonal growth.

Application of polymeric nanofibers in soft tissues regeneration

“…A design of a 3D scaffold consisting of parallel fibers embedded in a collagen matrix were developed. Using primary cultures of embryonic chicken DRGs, the results showed that PCL microfibers in the 3D matrix guide the direction of SC migration and axonal growth …”

Characterisation of cell–substrate interactions between Schwann cells and three‐dimensional fibrin hydrogels containing orientated nanofibre topographical cues

“…*P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001. astrocytes) and collagen hydrogels containing orientated nanofibres. Astrocytes have also been reported to adopt a range of morphological appearances in 3D collagen hydrogels, from simple, rounded cells to a stellate, multiprocess-bearing phenotype (Kriebel et al, 2014;Weightman et al, 2014). The stellate appearance probably reflects the normal morphology of such cells, as seen in the parenchyma of the central nervous system.…”

Photo-patterning PEG-based hydrogels for neuronal engineering

“…A number of different natural and synthetic biomaterials -together with well-defined fabrication techniques -have been used to prepare these neural scaffolds as NGCs. Some of the scaffold materials include collagen, fibrin, agarose, agarose derivatized with Laminin-1 or LN-1 peptides, Matrigel, PCL, PGA, PEG and HEMA [16,18,21,30,31]. Typically, these materials are fabricated with different internal structures or surface textures in order to create a microenvironment for guided axonal bundle regeneration.…”

“…The importance of spatial guidance in 3D biomaterials is exemplified in neural engineering where micro-patterns are used to promote neuronal development and orient neurite extensions [14][15][16][17][18][19][20][21][22][23][24]. For example, biomaterial-based nerve guidance conduits (NGCs) can be designed to treat severed peripheral nerves by promoting directional sprouting of axons and glial cells.…”

“…These scaffolds are thus created with numerous longitudinally orientated channels to guide single axons or axonal bundles. Alternatively, parallel aligned polymer fibers produced by melt extrusion or electrospinning are used for directional outgrowth of nerve fibers by contact guidance of axons [21,24,29,[31][32][33][34][35].…”