Cotransplant of neural stem cells and NT-3 gene modified Schwann cells promote the recovery of transected spinal cord injury

Abstract

Study design: An animal model of transected spinal cord injury (SCI) was used to test the hypothesis that cografted neural stem cells (NSCs) and NT-3-SCs promote morphologic and functional recoveries of injured spinal cord. Objective: To explore whether cotransplant of NSCs and NT-3-SCs could promote the injured spinal cord repair. Setting: Zhongshan Medical College, Sun Yat-sen University, PR China. Methods: Female Sprague-Dawley (SD) rats weighing on 200-220 g were used to prepare SCI models. The spinal cord was transected between T 9 and T 10 , then NSCs, SCs þ NSCs, LacZSCs þ NSCs, or NT-3-SCs þ NSCs were grafted into the transected site. Results: (1) Part of NSCs could differentiate to neuron-like cells in the transected site and the percentage of differentiation was NT-3-SCs þ NSCs group4SCs þ NSCs group4NSCs group. (2) In the grafted groups, there were 5-HT, CGRP, and SP positive nerve fibres within the transected site. Some fluorogold (FG)-labeled cells were found in the spinal cord rostral to the transected site, the red nuclei and the inner pyramidal layer of sensorimotor cortex. (3) The cells grafted could enhance the injured neurons survival in inner pyramidal layer of sensorimotor cortex, red nuclei of midbrain, and Clark's nuclei of spinal cord's L1 segment, could decrease the latency and increase the amplitude of cortical somatosensory evoked potential (CSEP) and cortical motor evoked potential (CMEP), and could promote partly structural and functional recovery of the SCI rats.Conclusion: These results demonstrate that cografted NT-3-SCs and NSCs is a potential therapy for SCI.

Coseeded Schwann cells myelinate neurites from differentiated neural stem cells in neurotrophin-3-loaded PLGA carriers

“…24 Exogenous NSCs transplantation was proposed to be a strategy for spinal cord regeneration. 3,12,21 However, whether these grafted cells are able to survive, differentiate into neurons, form myelin structures, and then re-establish a functioning neuronal network, remains unknown. In this study, we cocultured NSCs and SCs in NT-3-loaded PLGA carriers, and systemically investigated the survival and differentiation of cultured cells in relation to the nature of the scaffold matrix.…”

“…These results suggest that synaptic vesicles in our cultured neurons are able to fuse with the plasma membrane, with their contents diffusing into the pericellular compartment. 21,22 By contrast, neuronal cell bodies used as an experimental control showed no apparent change of fluorescence over time (see arrow in Figure 6G). …”

“…21,22 High K + levels stimulated recycling of endocytic synaptic vesicles containing FM1-43 or FM4-64. Scaffolds were then rinsed three times (for 15-20 minutes each time) in medium without FM1-43 or FM4-64, to bring endocytic/exocytotic activities to base level.…”

“…Cells cultured in the scaffold for 14 days were preloaded with FM1-43 or FM4-64, which stained recycling synaptic vesicles from endocytosis under depolarizing conditions (50 mM [K + ]). 21,22 In order to eliminate nonspecific labeling on the plasma membrane of neuronal cell body, cells in the PLGA scaffolds were rinsed extensively with PBS after the preloading process. A second depolarization was then induced by raising the K + concentration, which led to the release of FM1-43 or FM4-64 by exocytosis (Figure 6).…”

A Modular Assembly of Spinal Cord–Like Tissue Allows Targeted Tissue Repair in the Transected Spinal Cord

“…Immunofluorescence Staining : Specific proteins were detected using immunofluorescence staining as described in the previous publications 32, 37. Briefly, the sections were incubated with primary antibodies mixed in 0.3% Triton X‐100 at 4 °C overnight, followed by the incubation with secondary antibodies.…”