A novel in vitro assay for peripheral nerve-related cell migration that preserves both extracellular matrix-derived molecular cues and nanofiber-derived topography

Characterization of a Novel Aspect of Tissue Scarring Following Experimental Spinal Cord Injury and the Implantation of Bioengineered Type-I Collagen Scaffolds in the Adult Rat: Involvement of Perineurial-like Cells?

“…The ability of PNS-related glia to migrate into the injured spinal cord has been demonstrated in postmortem human tissues [ 60 , 61 , 62 , 63 ], as well as in a range of experimental models of SCI (induced by contusion, compression, or by penetration/laceration-type injuries) [ 26 , 27 , 60 , 64 , 65 , 66 ]. It is possible that reactive perineurial cells may migrate over a framework of locally deposited ECM molecules (e.g., fibronectin, collagen, and fibrin) to support such behaviour [ 67 ]. Perineurial cells have been reported to express alpha 3 integrin in vivo as well as alpha 2 and alpha 5 integrins in vitro, which recognise fibronectin, laminin, and various collagen sub-types [ 68 ].…”

Electrohydrodynamic Printing of Microfibrous Architectures with Cell‐Scale Spacing for Improved Cellular Migration and Neurite Outgrowth

“…[ 4–8 ] Once peripheral nerve tissues are injured, SCs from nerve stumps proliferate and migrate bidirectionally to form bands of Büngner to guide the directional growth of regenerated axons. [ 9–12 ] However, when the length of the never defects exceeds 5 mm, it is difficult to rely on the self‐regeneration of the axons to restore nerve function. [ 13,14 ] One promising strategy is to employ nerve tissue‐engineering scaffolds with biomimetic architectures to bridge the defected position for rapid migration of SCs and guided growth of axons.…”

Function Follows Form: Oriented Substrate Nanotopography Overrides Neurite-Repulsive Schwann Cell–Astrocyte Barrier Formation in an In Vitro Model of Glial Scarring

“…The fibers were transferred onto glass coverslips precoated with the ECM protein fibronectin (FN) as described previously. 33 FN was chosen because it is heavily deposited in areas of astroglial and connective tissue scarring after SCI. 46,47 Scanning electron microscopy (SEM) demonstrated the smooth surface and nanoscale dimensions of the fibers (Figure 1b,c).…”

“…14−25 The recently introduced elastic band spacer technique has the advantage of allowing cell migration and cell−cell interactions to be studied over user-defined combinations of ECM and fiber-derived topography within an initial, clearly delineated cell exclusion zone (CEZ). 33 The assay was designed such that the nanofiber arrays passed orthogonally between the cell fronts. The CEZ was subsequently filled by migrating SCs and ACs that encountered each other after 7 days (Figure S3 and Movie S1) and were allowed to interact for an additional 4 days following seeding of DRG onto the SC territory, resulting in a total culture time of 11 days.…”

“…The principle of cell geometry and orientation being associated with inherent cell function was strikingly demonstrated by Dike and colleagues, who reported that anisotropic substrates could influence the collective cell behavior of endothelial cells, resulting in the in vitro formation of tubular structures . The engineering of aligned fiber-based substrates on the micro- and nanometer scale has been demonstrated to mimic key features of the extracellular matrix (ECM), in particular its ability to provide potent orientational cues for a wide range of adherent cell types, including SCs and ACs. − …”