Table 1.
The main natural polymers used in neural tissue engineering, biocompatibility in vitro/in vivo, and examples of their applications
| Natural Polymer | Biocompatibility in vitro | Biocompatibility in vivo | Application | References |
|---|---|---|---|---|
| Pre-clinical Studies | ||||
| Collagen | Non-human primates | Nerve guide | [51, 52] | |
| Rats | Hydrogel/scaffold | [23, 28] | ||
| Dogs | Nerve conduits | [53] | ||
| Cats | Nerve conduits | [54] | ||
| Mice | Entubulation | [57] | ||
| DRGs | Entubulation | [58] | ||
| Rats | Entubulation | [59] | ||
| Fish Collagen | rBMSCs | No influence on neural differentiation | [63] | |
| Gelatin | hC-MSCs | Electrospun conduits | [66] | |
| PC12 | Electrospun conduits | [67] | ||
| C17.2 | Nerve conduits for Schwann cells | [68] | ||
| RT4-D6P2T | Nerve conduits for Schwann cells | [168] | ||
| PC12 | Nerve conduits for Schwann cells | [177] | ||
| Rats | Nerve conduit | [178, 181, 182] | ||
| Allogeneic rMSCs | Scaffold | [27] | ||
| Primary RSCs | Rats | Nanoparticles | [75] | |
| PC12 | Hybrid Scaffold | [184] | ||
| PC12 | Bioink | [77, 78] | ||
| Elastin | Mice | Thermally Responsive ELPs | [193] | |
| PC12 | ELPs Drug Depot | [194] | ||
| Rats | ELPs Intranasal Drug Delivery | [195] | ||
| Hyaluronic Acid | Rats | Hydrogel | [197] | |
| NPCs from forebrain cortical neuroepithelium of E13.5 rats | Hydrogel | [198] | ||
| C17.2 cells, ReNcells, GRPs | Hydrogel | [199] | ||
| DRGs | Hydrogel | [39] | ||
| NPCs | Hydrogel | [28, 202, 203] | ||
| Rabbits | Nerve Conduit | [189, 206] | ||
| Rats | Nerve Conduit | [48] | ||
| RSC96 | Nerve Conduit | [192] | ||
| NSCs | Drug Delivery | [93, 94] | ||
| PC12 | Nanoparticles | [207] | ||
| Cerebral cortices of Sprague–Dawley rats | Coating | [208] | ||
| Alginate | Cats | Gel | [209, 212, 213] | |
| Rats | Gel | [210] | ||
| Rats | Sponge | [211, 215, 216] | ||
| PDLMSCs and GMSCs | Hybrid scaffold | [217] | ||
| PC12 | Hybrid scaffold | [95] | ||
| NSCs | Hybrid scaffold | [218] | ||
| Rats | Hybrid scaffold | [108–111] | ||
| Chitosan | PC12 | Hydrogel | [26, 76, 120] | |
| NPCs from forebrain cortical neuroepithelium of C57 fetal rats | Hydrogel | [113] | ||
| NSCs | Hydrogel | [114, 115] | ||
| Neuro-2a | Scaffold | [116] | ||
| Schwann cells from Sprague-Dawley rats | Scaffold | [117, 118, 123–125]. | ||
| U373 | Nanotubes | [119] | ||
| BMSCs | Scaffold | [121] | ||
| Dogs | Scaffold | [122] | ||
| GFP+RG3.6 | Micro/nano vehicle | [126] | ||
| Rats | Micro/nano vehicle | [34, 127] | ||
| Mice | Micro/nano vehicle | [128] | ||
| hNSC | Bioink | [129] | ||
| Keratin | Mice | Nerve guide | [131, 132, 134] | |
| RT4-D6P2T | Mice | Hydrogel | [133] | |
| Rabbits | Hydrogel | [135] | ||
| Primates | Hydrogel | [136] | ||
| Glial cells | Nanofibrous Scaffold | [137] | ||
| Silk | NSCs | Hydrogel | [30, 141] | |
| Rats | Hydrogel | [39] | ||
| DRGs | Hydrogel | [139, 140, 143, 145, 147] | ||
| Primary Hippocampal Neurons | Scaffold | [144] | ||
| PC12 | Electrospun scaffold | [146] | ||
| Rats | Electrospun scaffold | [39, 40] | ||
| Dogs | Electrospun scaffold | [24] | ||
| Rats | Nerve Guide | [148] | ||
| Rats | Electrode Coating | [149] | ||
| Glial Scarring | Electrode Coating | [150] | ||
| NT2 | Nerve guide (spider silk) | [151] | ||
| NSCs | Matrix (spider silk) | [152] | ||
| Clinical Studies | ||||
| Collagen | Peripheral nerve reconstruction | NeuraGen® | [55] | |
| Peripheral nerve reconstruction | Neuromaix® | [56] | ||
DRGs: dorsal root ganglia; rBMSCs: rat bone marrow mesenchymal stem cells; hC-MSCs: human chorion mesenchymal stem cells; rMSCs: rat mesenchymal stromal cells; RSCs: rat Schwann cells; ELPs: elastin-like polypeptides; NPCs: neural progenitor cells; GRPs: human glial-restricted precursors; PDLMSCs: human periodontal ligament mesenchymal stem cells; GMSCs: gingiva-derived mesenchymal stem cells; NSCs: neural stem cells; BMSCs: bone marrow stromal cells; hNSCs: human neural stem cells.