scholarly journals In Vivo and In Vitro Evaluation of a Novel Hyaluronic Acid–Laminin Hydrogel as Luminal Filler and Carrier System for Genetically Engineered Schwann Cells in Critical Gap Length Tubular Peripheral Nerve Graft in Rats

2020 ◽  
Vol 29 ◽  
pp. 096368972091009
Author(s):  
Nina Dietzmeyer ◽  
Zhong Huang ◽  
Tobias Schüning ◽  
Shimon Rochkind ◽  
Mara Almog ◽  
...  
Keyword(s):  
Gene Expression ◽  
Hyaluronic Acid ◽  
Peripheral Nerve ◽  
Schwann Cells ◽  
Chitosan Film ◽  
Nerve Graft ◽  
Motor Recovery ◽  
Carrier System ◽  
Nerve Guides

In the current study we investigated the suitability of a novel hyaluronic acid–laminin hydrogel (HAL) as luminal filler and carrier system for co-transplanted cells within a composite chitosan-based nerve graft (CNG) in a rat critical nerve defect model. The HAL was meant to improve the performance of our artificial nerve guides by giving additional structural and molecular support to regrowing axons. We filled hollow CNGs or two-chambered nerve guides with an inserted longitudinal chitosan film (CNG[F]s), with cell-free HAL or cell-free HA or additionally suspended either naïve Schwann cells (SCs) or fibroblast growth factor 2-overexpressing Schwann cells (FGF2-SCs) within the gels. We subjected female Lewis rats to immediate 15 mm sciatic nerve gap reconstruction and comprehensively compared axonal and functional regeneration parameters with the gold standard autologous nerve graft (ANG) repair. Motor recovery was surveyed by means of electrodiagnostic measurements at 60, 90, and 120 days post-reconstruction. Upon explantation after 120 days, lower limb target muscles were harvested for calculation of muscle-weight ratios. Semi-thin cross-sections of nerve segments distal to the grafts were evaluated histomorphometrically. After 120 days of recovery, only ANG treatment led to full motor recovery. Surprisingly, regeneration outcomes revealed no regeneration-supportive effect of HAL alone and even an impairment of peripheral nerve regeneration when combined with SCs and FGF2-SCs. Furthermore, complementary in vitro studies, conducted to elucidate the reason for this unexpected negative result, revealed that SCs and FGF2-SCs suspended within the hydrogel relatively downregulated gene expression of regeneration-supporting neurotrophic factors. In conclusion, cell-free HAL in its current formulation did not qualify for optimizing regeneration outcome through CNG[F]s. In addition, we demonstrate that our HAL, when used as a carrier system for co-transplanted SCs, changed their gene expression profile and deteriorated the pro-regenerative milieu within the nerve guides.

scholarly journals Interleukin-4 Regulates the Expression of CD209 and Subsequent Uptake of Mycobacterium leprae by Schwann Cells in Human Leprosy

2010 ◽  
Vol 78 (11) ◽  
pp. 4634-4643 ◽  
Author(s):  
Rosane M. B. Teles ◽  
Stephan R. Krutzik ◽  
Maria T. Ochoa ◽  
Rosane B. Oliveira ◽  
Euzenir N. Sarno ◽  
...  
Keyword(s):  
Schwann Cell ◽  
Peripheral Nerve ◽  
Schwann Cells ◽  
Primary Cultures ◽  
Mycobacterium Leprae ◽  
Microbial Pathogens ◽  
Interleukin 4 ◽  
Common Mechanism ◽  
Specific Cell

ABSTRACT The ability of microbial pathogens to target specific cell types is a key aspect of the pathogenesis of infectious disease. Mycobacterium leprae, by infecting Schwann cells, contributes to nerve injury in patients with leprosy. Here, we investigated mechanisms of host-pathogen interaction in the peripheral nerve lesions of leprosy. We found that the expression of the C-type lectin, CD209, known to be expressed on tissue macrophages and to mediate the uptake of M. leprae, was present on Schwann cells, colocalizing with the Schwann cell marker, CNPase (2′,3′-cyclic nucleotide 3′-phosphodiesterase), along with the M. leprae antigen PGL-1 in the peripheral nerve biopsy specimens. In vitro, human CD209-positive Schwann cells, both from primary cultures and a long-term line, have a higher binding of M. leprae compared to CD209-negative Schwann cells. Interleukin-4, known to be expressed in skin lesions from multibacillary patients, increased CD209 expression on human Schwann cells and subsequent Schwann cell binding to M. leprae, whereas Th1 cytokines did not induce CD209 expression on these cells. Therefore, the regulated expression of CD209 represents a common mechanism by which Schwann cells and macrophages bind and take up M. leprae, contributing to the pathogenesis of leprosy.

In Vitro Evaluation of the Growth and Migration of Schwann Cells on Electrospun Silk Fibroin Nanofibers

2011 ◽  
Vol 175-176 ◽  
pp. 220-223 ◽  
Author(s):  
Ai Jun Hu ◽  
Bao Qi Zuo ◽  
Feng Zhang ◽  
Qing Lan ◽  
Huan Xiang Zhang
Keyword(s):  
Tissue Engineering ◽  
Peripheral Nerve ◽  
Nerve Regeneration ◽  
Schwann Cells ◽  
Silk Fibroin ◽  
Nerve Tissue ◽  
Nerve Tissue Engineering ◽  
And Migration ◽  
Silk Fibroin Nanofibers

Schwann cells (SCs) are primary structural and functional cells in peripheral nervous system and play a crucial role in peripheral nerve regeneration. Current challenge in peripheral nerve tissue engineering is to produce an implantable scaffold capable of bridging long nerve gaps and assist Scs in directing the growth of regenerating axons in nerve injury recovery. Electrospun silk fibroin nanofibers, fabricated for the cell culture in vitro, can provide such experiment support. Silk fibroin scaffolds (SFS) were fabricated with formic acid (FA), and the average fiber diameter was 305 ± 24 nm. The data from microscopic, immunohistochemical and scanning electron micrograph confirmed that the scaffold was beneficial to the adherence, proliferation and migration of SCs without exerting any significant cytotoxic effects on their phenotype. Thus, providing an experimental foundation accelerated the formation of bands of Bünger to enhance nerve regeneration. 305 nm SFS could be a candidate material for nerve tissue engineering.

Preparation and characterization of injectable chitosan–hyaluronic acid hydrogels for nerve growth factor sustained release

2016 ◽  
Vol 32 (2) ◽  
pp. 146-162 ◽  
Author(s):  
Haixing Xu ◽  
Lingxi Zhang ◽  
Yun Bao ◽  
Xiumei Yan ◽  
Yixia Yin ◽  
...  
Keyword(s):  
Hyaluronic Acid ◽  
Nerve Growth Factor ◽  
Growth Factor ◽  
Peripheral Nerve ◽  
Sustained Release ◽  
Peripheral Nerve Regeneration ◽  
Nerve Growth ◽  
Nerve Conduits ◽  
Hyaluronic Acid Hydrogel

The usage of hollow nerve conduits shows inferior recovery effect on the repair of peripheral nerve defects. In this study, a biocompatible and biodegradable pH-induced injectable chitosan–hyaluronic acid hydrogel for nerve growth factor encapsulation and sustained release was developed as the fillers in the lumen of hollow nerve conduit to reform its microenvironment for peripheral nerve regeneration. The physicochemical properties of hydrogel were characterized by gelation time, Fourier transform infrared spectroscopy, scanning electron microscopy, compressive modulus, porosity, swelling ratio, and in vitro degradation. The in vitro nerve growth factor release profiles and cell evaluation were also investigated. The results show that the structure of chitosan–hyaluronic acid hydrogel is composed of interconnected channels with a controllable pore diameter ranging from 20 to 100 µm. The hydrogel can be degraded more than 70% within 8 weeks in vitro and is available for nerve growth factor sustained release. The chitosan–hyaluronic acid/nerve growth factor hydrogel is non-toxic and suitable for adhesion and proliferation of nerve cells and capable of maintaining nerve growth factor activity. Therefore, it could be a promising intraluminal filler of nerve conduits for peripheral nerve regeneration in neural tissue engineering.

Producing Neurospheroids and Hydrogels to Create a Three-dimensional in Vitro Model for the Use of Conduits in Peripheral Nerve Regeneration

Neurosurgery ◽  
2019 ◽  
Vol 84 (5) ◽  
pp. E272-E272
Author(s):  
Devyani Shete ◽  
Aran Batth ◽  
Aditi Nijhawan ◽  
Jaffer Choudhary ◽  
Ian Thompson
Keyword(s):  
Peripheral Nerve ◽  
Nerve Regeneration ◽  
Schwann Cells ◽  
Peripheral Nerve Regeneration ◽  
3D Structure ◽  
Three Dimensional ◽  
Negative Control ◽  
Cellular Growth ◽  
Live Cells

Abstract INTRODUCTION Peripheral nerve regeneration is a complex challenge that requires suitable nerve guidance systems to bridge the severed ends of 2 nerves back together. Current polymeric conduits on the market provide good cellular growth but are limited by the length of gap defect they can repair, and complete functional recovery is rare. This project focused on creating a three-dimensional (3D) in Vitro spheroidal sprouting assay for peripheral nerve regeneration, as well as producing and testing different polymeric hydrogels as potential scaffold materials for the conduit. METHODS Different concentrations of chitosan, methylcellulose (MC) and sodium alginate were produced, as well as blends of these materials. These hydrogels were seeded with 3D neurospheroids, along with NG108-15 (neuronal) cells and Schwann cells to test their biocompatibility. RESULTS MTT assays showed the mean absorbance of chitosan gels with NG108-15 cells at 24 hr (P < .001) and 72 hr (P > .05) was similar/slightly higher than the negative control. Live-Dead data showed 93.4% of live cells at DIV7 on MC: Ch blends, compared to 72% with chitosan alone. CONCLUSION Overall, both chitosan and MC were nontoxic and biocompatible with NG108-15 and Schwann cells. Blending chitosan with MC improved its chemical and physical properties. The cells formed spheroids that well on a gel; this pseudo-3D structure is excellent for research purposes compared to 2D as it mimics the body's internal environment.

scholarly journals BMP-7/Smad expression in dedifferentiated Schwann cells during axonal regeneration and upregulation of endogenous BMP-7 following administration of PTH (1-34)

2018 ◽  
Vol 26 (3) ◽  
pp. 230949901881295 ◽  
Author(s):  
Naoki Kokubu ◽  
Masaya Tsujii ◽  
Koji Akeda ◽  
Takahiro Iino ◽  
Akihiro Sudo
Keyword(s):  
Peripheral Nerve ◽  
Schwann Cells ◽  
Nerve Injury ◽  
Axonal Regeneration ◽  
Double Immunostaining ◽  
Aneurysm Clip ◽  
Smad Signaling ◽  
Bmp Receptors ◽  
Smad Protein

Purpose: To determine the expression and distribution of bone morphogenetic protein (BMP)-7 and related molecules during peripheral nerve regeneration and to assess whether administration of parathyroid hormone (PTH) drug (1-34) potentiates the intrinsic upregulation of BMP-7/Smad signaling. Methods: The rat sciatic nerves were crushed with an aneurysm clip resulting in axonal degeneration. In the normal nerve, and at 1, 2, 4, and 8 weeks after injury, BMP-7, BMP receptors, p-Smad 1/5/8, and Noggin, the endogenous BMP antagonist, were evaluated. Additionally, the distribution of BMP-7 was assessed by fluorescent double immunostaining. In vitro studies were also performed to examine the effect of BMP-7 and PTH (1-34) administration on rat Schwann cells (SCs). Results: Aneurysm clip made reliable animal model of the nerve injury with recovery at 8 weeks after the injury. BMP-7/Smad protein and mRNA were significantly upregulated on axon-SCs units at 1 week after injury, and this upregulated expression was maintained for 4 weeks. Besides, significant upregulation of Noggin’s expression was observed on axon-SCs units at 2 weeks after injury. Moreover, fluorescent double immunostaining showed co-localization between expression of BMP-7 and p75NTR during axonal regeneration. In the in vitro study, administration of BMP-7 induced significant proliferation of SCs. Application of PTH (1-34) upregulated BMP-7 on SCs. Discussion/conclusion: BMPs were reported to be involved in protection and recovery after injury as well as in neurogenesis. Our current study showed that BMP/Smad signaling molecules were upregulated on dedifferentiated SCs after peripheral nerve injury and that administration of BMP-7 increased SC viability in vitro. These results suggested that axonal regeneration could be induced via upregulation of endogenous BMP-7 on SCs by PTH (1-34) administration.

scholarly journals Electrospun Hyaluronan-Gelatin Nanofibrous Matrix for Nerve Tissue Engineering

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Hau-Min Liou ◽  
Lih-Rou Rau ◽  
Chun-Chiang Huang ◽  
Meng-Ru Lu ◽  
Fu-Yin Hsu
Keyword(s):  
Peripheral Nerve ◽  
Schwann Cells ◽  
Cell Attachment ◽  
Nerve Repair ◽  
Critical Role ◽  
Nerve Tissue ◽  
Growth Environment ◽  
Biological Performance ◽  
Electrospun Gelatin

Schwann cells play a critical role in the repair of the peripheral nerve. The goal of this study was to fabricate electrospun gelatin (Gel) and hyaluronan-gelatin (HA-Gel) composite nanofibers to provide a suitable growth environment for Schwann cells. The fiber diameters of Gel, 0.5 HA-Gel, 1 HA-Gel, and 1.5 HA-Gel were 130 ± 30 nm, 294 ± 87 nm, 362 ± 129 nm, and 224 ± 54 nm, respectively. The biological performance of Gel and HA-Gel was evaluated using anin vitroculture of RT4-D6P2T rat Schwann cells. We found that the cell attachment and proliferation rates were not significantly different on these matrices. However, the Schwann cells displayed better organized F-actin on HA-Gel than on Gel. Moreover, the expression levels of several genes, including Nrg1, GFAP, and P0, were significantly higher on HA-Gel than on Gel. In addition, the levels of Nrg1 and P0 protein expression were also higher on the HA-Gel than on Gel. These results indicate that the hyaluronan-gelatin composite nanofibrous matrix could potentially be used in peripheral nerve repair.

Regulating Schwann Cells Growth by Chitosan Micropatterning for Peripheral Nerve Regeneration In Vitro

2014 ◽  
Vol 14 (8) ◽  
pp. 1067-1075 ◽  
Author(s):  
Guicai Li ◽  
Xueying Zhao ◽  
Luzhong Zhang ◽  
Caiping Wang ◽  
Yunwei Shi ◽  
...  
Keyword(s):  
Peripheral Nerve ◽  
Nerve Regeneration ◽  
Schwann Cells ◽  
Peripheral Nerve Regeneration ◽  
Regeneration In Vitro
Sign in / Sign up

Export Citation Format

Share Document