Cell transplantation
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Cell transplantation · Jan 2012
Long-term outcome of olfactory ensheathing cell therapy for patients with complete chronic spinal cord injury.
The neurorestorative effect of the parenchymal transplantation of olfactory ensheathing cells (OECs) for cord trauma remains clinically controversial. The aim of this article is to study the long-term result of OECs for patients with complete chronic spinal cord injury (SCI). One hundred and eight patients suffered from complete chronic SCI were followed up successfully within the period of 3.47 ± 1.12 years after OEC therapy. ⋯ Nine of them (8.33%) improved their walk ability or made them rewalk by using a walker with or without assistance; 12 of 84 men (14.29%) improved their sex function. 5) MRI examinations were taken for 31 patients; there were no neoplasm, bleeding, swelling, cysts, neural tissue destruction or infection (abscess) or any other pathological changes in or around OEC transplant sites. 6) EMG examinations were done on 31 patients; 29 showed improvement and the remaining 2 had no change. PVSEP tests were performed in 31 patients; 28 showed improvements and the remaining 3 had no change. 7) No deterioration or complications were observed in our patients within the follow-up period. Our data suggest OEC therapy is safe and can improve neurological functions for patients with complete chronic SCI and ameliorate their quality of life; the AMTENT most likely plays a critical role in enhancing functional recovery after cell-based neurorestorotherapy.
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Cell transplantation · Jan 2012
The effect of growth factors and soluble Nogo-66 receptor protein on transplanted neural stem/progenitor survival and axonal regeneration after complete transection of rat spinal cord.
Adult central mammalian axons show minimal regeneration after spinal cord injury due to loss of oligodendrocytes, demyelination of surviving axons, absence of growth-promoting molecules, and inhibitors of axonal outgrowth. In the present study, we attempted to address these impediments to regeneration by using a combinatory strategy to enhance cell survival and regeneration after complete spinal cord transection (SCT) in adult rats. The strategy comprised: 1) adult rat brain-derived neural stem/progenitor cells (NSPCs) preseeded on laminin-coated chitosan channels; 2) extramedullary chitosan channels to promote axonal regrowth and reduce the barrier caused by scarring; 3) local delivery of a novel rat soluble Nogo-66 receptor protein [NgR(310)ecto-Fc, referred to as NgR] to block the inhibitory effect of myelin-based inhibitors; and 4) local delivery of basic fibroblast growth factor, epidermal growth factor, and platelet-derived growth factor to enhance survival and promote differentiation of transplanted cells. ⋯ However, only a small number of descending corticospinal tract axons grew into the central portions of the bridges as shown by anterograde tracing of the corticospinal tract with BDA. The majority of the regenerated axons in the channels originated from local host neurons adjacent to the tissue bridges. In conclusion, we showed that growth factors increased survival of transplanted NSPCs whereas NgR enhanced axonal regeneration, but the combination did not have additive effects on functional recovery or regeneration.
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Cell transplantation · Jan 2012
Endothelial progenitor cells improve directly and indirectly early vascularization of mesenchymal stem cell-driven bone regeneration in a critical bone defect in rats.
Early vascularization of a composite in a critical bone defect is a prerequisite for ingrowth of osteogenic reparative cells to regenerate bone, since lack of vessels does not ensure a sufficient nutritional support of the bone graft. The innovation of this study was to investigate the direct and indirect effects of endothelial progenitor cells (EPCs) and cotransplanted mesenchymal stem cells (MSCs) on the in vivo neovascularization activity in a critical size defect at the early phase of endochondral ossification. Cultivated human EPCs and MSCs were loaded onto β-TCP in vitro. ⋯ Transplanted EPC release chemotactic factors (VEGF) to recruit EPCs of the host and stimulate vascularization in the bone defect. Transplantation of human EPCs displays a promising approach to improve early vascularization of a scaffold in a critical bone defect. Moreover, coculture of EPCs and MSCs demonstrate also a synergistic effect on new vessel formation and seems to be a potential osteogenic construct for in vivo application.
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Cell transplantation · Jan 2012
Tissue augmentation by white blood cell-containing platelet-rich plasma.
Platelet-rich plasma (PRP) is a matrix of fibrin and platelets that releases cytokines that are important in wound healing. PRP is produced from the patient's blood and therefore has less risk of allergic reaction and infection. We have obtained PRP with an enhanced white blood cell component (W-PRP) by optimizing the centrifugal separation of PRP from plasma. ⋯ Further augmentation occurred when bFGF was added to W-PRP, and there was a significant increase in the number of α-smooth muscle actin-positive cells in mice treated with W-PRP+bFGF. Our results suggest that W-PRP may have value in cosmetic surgery aimed at rejuvenation of wrinkled and sagging skin. W-PRP injection constitutes a new concept in cell transplantation, in which cells required for tissue regeneration are induced by cytokines released from the transplanted cells.
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Cell transplantation · Jan 2011
Neural differentiation of brain-derived neurotrophic factor-expressing human umbilical cord blood-derived mesenchymal stem cells in culture via TrkB-mediated ERK and β-catenin phosphorylation and following transplantation into the developing brain.
The ability of mesenchymal stem cells (MSCs) to differentiate into neural cells makes them potential replacement therapeutic candidates in neurological diseases. Presently, overexpression of brain-derived neurotrophic factor (BDNF), which is crucial in the regulation of neural progenitor cell differentiation and maturation during development, was sufficient to convert the mesodermal cell fate of human umbilical cord blood-derived MSCs (hUCB-MSCs) into a neuronal fate in culture, in the absence of specialized induction chemicals. BDNF overexpressing hUCB-MSCs (MSCs-BDNF) yielded an increased number of neuron-like cells and, surprisingly, increased the expression of neuronal phenotype markers in a time-dependent manner compared with control hUCB-MSCs. ⋯ In addition, inhibition of β-catenin and ERKs expression levels abrogated the BDNF-stimulated upregulation of neuronal phenotype markers. Furthermore, MSC-BDNF survived and migrated more extensively when grafted into the lateral ventricles of neonatal mouse brain, and differentiated significantly into neurons in the olfactory bulb and periventricular astrocytes. These results indicate that BDNF induces the neural differentiation of hUCB-MSCs in culture via the TrkB-mediated phosphorylation of ERKs and β-catenin and following transplantation into the developing brain.