Nano-fibrous and ladder-like multi-channel nerve conduits: Degradation and modification by gelatin.

We recently fabricated multi-channel PLLA nerve conduits (NCs, conduits diameter: ~3mm, channels diameter: ~200μm) with nano-fibrous microstructure (NNCs) and ladder-like microstructure (LNCs), and found the nanofibers in the NNCs promote differentiation of nerve stem cells (NSCs) into neurons. In the present study, we evaluated the degradation profile of NNCs and LNCs, and observed that NNCs degraded too fast to implant. To delay the degradation and retain the nano-scale effect of NNCs, we used gelatin to wrap (2% w/v gelatin) or embed (8% w/v gelatin) NNCs and LNCs via vacuum infusion and chemical cross-linking with genipin.

Fabrication and evaluation of PLLA multichannel conduits with nanofibrous microstructure for the differentiation of NSCs in vitro.

Nerve conduits (NCs) with multiple longitudinally aligned channels, being mimicking the natural nerves anatomical structure, have been attracted more and more attentions. However, some specific structural parameters of a conduit that would be beneficial for further improvement of neural tissue regeneration were not comprehensively considered. Using a systematized device and combining low-pressure injection molding and thermal-induced phase separation, we fabricated 33-channel NCs (outer diameter 3.

A comparative study of gelatin sponge scaffolds and PLGA scaffolds transplanted to completely transected spinal cord of rat.

This study sought to investigate whether gelatin sponge (GS) scaffold would produce less acidic medium in injured spinal cord, as compared with poly(lactic-co-glycolic acid) (PLGA) scaffold, to determine which of the two scaffolds as the biomaterial is more suitable for transplantation into spinal cord. GS scaffold or PLGA scaffold was transplanted into a transected spinal cord in this study. Two months after transplantation of scaffolds, acid sensing ion channel 1a (ASIC1a) positive cells expressing microtubule associated protein 2 (Map2) were observed as well as expressing adenomatous polyposis coli (APC) in spinal cord.

[Fabrication of tissue engineered vein containing valve scaffolds].

Objective: To fabricate porous biodegradable tissue engineered vein containing valve scaffolds.

Methods: Based on the self-made cast, the tissue engineered vein containing valve scaffolds was fabricated by injection molding plus thermally induced phase separation. Poly (lactic-co-glycolic acid) (PLGA, LA/GA mole ratio 75:25) was used as matrices.

Neurotrophin-3 gene-modified Schwann cells promote TrkC gene-modified mesenchymal stem cells to differentiate into neuron-like cells in poly(lactic-acid-co-glycolic acid) multiple-channel conduit.

Rapid progress in the field of nerve tissue engineering has opened up the way for new therapeutic strategies for spinal cord injury (SCI). Bone marrow-derived mesenchymal stem cells (MSCs) could be differentiated into neural lineages, which can be used as a potential cell source for nerve repair. Schwann cells (SCs) have been reported to support structural and functional recovery of SCI.

Transplantation of artificial neural construct partly improved spinal tissue repair and functional recovery in rats with spinal cord transection.

Delivery of cellular and/or trophic factors to the site of injury may promote neural repair or axonal regeneration and return of function after spinal cord injury. Engineered scaffolds provide a platform to deliver therapeutic cells and neurotrophic molecules. To explore therapeutic potential of engineered neural tissue, we generated an artificial neural construct in vitro, and transplanted this construct into a completely transected spinal cord of adult rats.

Synaptic transmission of neural stem cells seeded in 3-dimensional PLGA scaffolds.

To explore therapeutic potential of engineered neural tissue, we combined genetically modified neural stem cells (NSCs) and poly(lactic acid-co-glycolic acid) (PLGA) polymers to generate an artificial neural network in vitro. NSCs transfected with either NT-3 or its receptor TrkC gene were seeded into PLGA scaffold. The NSCs were widely distributed and viable in the scaffold after culturing for 14 days.