Neuroregenerative effects of olfactory ensheathing cells transplanted in a multi-layered conductive nanofibrous conduit in peripheral nerve repair in rats

Abstract

BackgroundThe purpose of this study was to evaluate the efficacy of a multi-layered conductive nanofibrous hollow conduit in combination with olfactory ensheathing cells (OEC) to promote peripheral nerve regeneration. We aimed to harness both the topographical and electrical cues of the aligned conductive nanofibrous single-walled carbon nanotube/ poly (L-lactic acid) (SWCNT/PLLA) scaffolds along with the neurotrophic features of OEC in a nerve tissue engineered approach.ResultsWe demonstrated that SWCNT/PLLA composite scaffolds support the adhesion, growth, survival and proliferation of OEC. Using microsurgical techniques, the tissue engineered nerve conduits were interposed into an 8 mm gap in sciatic nerve defects in rats. Functional recovery was evaluated using sciatic functional index (SFI) fortnightly after the surgery. Histological analyses including immunohistochemistry for S100 and NF markers along with toluidine blue staining (nerve thickness) and TEM imaging (myelin sheath thickness) of the sections from middle and distal parts of nerve grafts showed an increased regeneration in cell/scaffold group compared with cell-free scaffold and silicone groups. Neural regeneration in cell/scaffold group was very closely similar to autograft group, as deduced from SFI scores and histological assessments.ConclusionsOur results indicated that the tissue engineered construct made of rolled sheet of SWCNT/PLLA nanofibrous scaffolds and OEC could promote axonal outgrowth and peripheral nerve regeneration suggesting them as a promising alternative in nerve tissue engineering.

In vivo feasibility test using transparent carbon nanotube‐coated polydimethylsiloxane sheet at brain tissue and sciatic nerve

“…For example, Ahn et al reported the in vivo functions of CNT‐interfaced nerve conduits in the regeneration of transected rat sciatic nerve . Kabiri et al evaluated the efficacy of a multilayered conductive nanofibrous hollow conduit in harnessing both the topographical and electrical cues of the aligned conductive nanofibrous single‐walled carbon nanotube/poly (L‐lactic acid) (SWCNT/PLLA) scaffolds . Furthermore, incorporation of 1–3 wt % multiwalled carbon nanotubes (MWNTs) and 5–8 wt % poly(3‐hexylthiophene‐2,5‐diyl) (P3HT) increased the Young's Modulus by 10% and 20%, respectively, compared with using pure poly‐caprolactone .…”

Establishing a reliable gait evaluation method for rodent studies

“…This method is currently popular in peripheral nerve regeneration research, and is widely considered as the gold standard evaluative tool (Gan et al, 2016; Kabiri et al, 2015; Lin et al, 2013). As expected, our results very clearly showed differences in recovery between experimental groups, and the Autograft and NCSC groups both showed improvements over time.…”

“…For each group, half was euthanized at 6 weeks, and the other at 12 weeks. We used postmortem histomorphometric analysis as a reference to justify results derived from the CatWalk system since histomorphometric analysis is widely used in current studies as a gold standard for evaluating recovery following sciatic nerve injury (Gan et al, 2016; Kabiri et al, 2015; Lin et al, 2013). We have described the methods of histomorphometric analysis in past studies (Johnson et al, 2015).…”

Current status of stem cell therapy: opportunities and limitations

“…The use of stem cells in neural differentiation/ neuroregeneration was also reported, such as for induction of motor neuron differentiation applied with complex matrices that included collagen grafted nanofibers (Bagher et al, 2015), or peripheral nerve repair with single-walled carbon nanotubes/poly-lactic acid scaffolds (Kabiri et al, 2015).…”