T Lymphocyte Subsets and Cytokines in Rats Transplanted with Adipose-Derived Mesenchymal Stem Cells and Acellular Nerve for Repairing the Nerve Defects

OBJECTIVE: The aim of this study was to explore the immunity in rats transplanted with adipose-derived mesenchymal stem cells (ADSCs) and acellular nerve (ACN) for repairing sciatic nerve defects. METHODS: ADSCs were isolated from the adipose tissues of Wistar rats. Sprague-Dawley rats were used to establish a sciatic nerve defect model and then divided into four groups, according to the following methods : Group A, allogenic nerve graft; Group B, allograft with ACN; Group C, allograft ADSCs+ACN, and Group D, nerve autograft. RESULTS: At the day before transplantation and 3, 7, 14, and 28 days after transplantation, orbital venous blood of the Sprague-Dawley rats in each group was collected to detect the proportion of CD3+, CD4+, and CD8+ subsets using flow cytometry and to determine the serum concentration of interleukin-2 (IL-2), tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma) using enzyme-linked immunosorbent assay (ELISA). At each postoperative time point, the proportion of CD3+, CD4+, and CD8+ subsets and the serum concentration of IL-2, TNF-alpha, and IFN-gamma in group C were all near to those in group B and group D, in which no statistically significant difference was observed. As compared with group A, the proportion of CD3+, CD4+, and CD8+ subsets and the serum concentration of IL-2, TNF-alpha, and IFN-gamma were significantly reduced in group C (p<0.05). CONCLUSION: The artificial nerve established with ADSCs and ACN has no obvious allograft rejection for repairing rat nerve defects.

Effects of dopaminergic neurons differentiated from mesencephalic NSCs induced by transplantation on treatment of Parkinson's disease in rats / 第三军医大学学报

Objective To evaluate the therapeutical effect of dopaminergic neurons induced by transplantation on Parkinson's disease (PD) rats. Methods Mesencephalic nerve stem cells (NSCs) were induced by striatal extracts to differentiate into tyroxine hydroxylase (TH) positive dopaminergic neurons. The differentiated cells were transplanted into the striatum of PD rats. The survived cells were detected by TH immunocytochemical staining. The therapeutical effect was observed using apomorphine induced rotation. Results Mesencephalic NSCs could be induced to differentiate into dopaminergic neurons which could survive in the host for long time after cell transplantation, and could improve the apomorphine induced rotation. Conclusion The induced mesencephalic NSCs have the obvious therapeutical effect on PD.

Human Neural Stem Cells Transplantation in Experimental Intracerebral Hemorrhage

BACKGROUND: Intracerebral hemorrhage (ICH) is associated with a considerable proportion of stroke and head injuries, but except for supportive care, there is no medical therapy available. Transplantation of human neural stem cells (NSCs) can be used to reduce behavioral deficit in experimental ischemic infarct model. However, effect of stem cell transplantation in experimental intracerebral hemorrhage (ICH) is unknown. We hypothesized that NSCs could migrate and differentiate into neurons or glial cells, and improve functional outcome in ICH. METHODS: Experimental ICH was made by intrastriatal administration of bacterial collagenase in adult rats. Animals were randomized to receive intravenously either immortalized Lac-Z positive human NSCs (5x1 06 in 500microL, n=15) or same volume of saline (n=12) on the following day. Animals were evaluated for 8 weeks after surgery with behavioral test battery. After 8 weeks, animals were sacrificed and the brains were sectioned. Transplanted NSCs were detected by X-gal histochemistry or beta-gal immunohistochemistry, and differentiation of grafted NSCs were evaluated by double labeling of GFAP, NeuN, or neurofilament. RESULTS: Transplanted NSCs migrated to the side of peri-hematomal areas, and differentiated into neurons and astrocytes. NSCs injection group showed improved performances on rotarod test after 2 weeks and on limb placing test after 5 weeks compared with control group (p<0.05) and these effect persisted up to 8 weeks. CONCLUSIONS: Intravenously injected NSCs enter rat brain with ICH, and differentiate into astrocytes or neuronal cell, which lead to functional recovery. These findings show the possibility that NSCs can be used to reduce neurological deficits in the experimental ICH.

Neural Stem Cells

Multipotent neural stem cells (NSCs) are operationally defined by their ability to self-renew, to differentiate into cells of all glial and neuronal lineages throughout the neuraxis, and to populate developing or degenerating CNS regions. Thus their use as a graft material can be considered analogous to hematopoietic stem cell-mediated reconstitution and gene transfer. The recognition that NSCs propagated in culture could be reimplanted into mammalian brain, where they might integrate appropriately throughout the mammalian CNS and stably express foreign genes, has unveiled a new role for neural transplantation and gene therapy and a possible strategy for addressing the CNS manifestations of diseases that heretofore has been refractory to intervention. We have tracked the response of host and transplanted NSCs to brain or spinal cord injury and explored the therapeutic potential of NSCs injected into the animal CNS subjected to focal hypoxic-ische-mic (HI) brain or spinal cord injury. Such cells integrated appropriately into the degenerating CNS, showed robust engraftment and foreign gene expression within the region of CNS injury, and appeared to have migrated preferentially to the site of injury, experienced limited proliferation, and differentiated into neural cells lost to injury, trying to repopulate the damaged CNS area. The transplantation of exogenous NSCs may, in fact, augment a natural self-repair process in which the damaged CNS "attempts" to mobilize its own pool of stem cells. Providing additional NSCs and trophic factors may optimize this response. Therefore, NSCs may provide a novel approach to reconstituting CNS damaged by HI brain or spinal cord injury. Preliminary data in animal models of hypoxic-ischemic brain injury or contusive spinal cord injury lend support to these hypotheses.

Transplantation of fetal neocortex in rhesus monkey.

A feasibility study of neural transplantation in adult rhesus monkey was undertaken. Fresh and preserved neocortex containing multiplying and maturing neurons obtained from 55-70 gestation days were transplanted into the striatum, cerebellum and cerebral cortex of adult monkeys. Tissues were preserved for 4 days either at subzero temperature in the freezer compartment of the ordinary refrigerator in Ringer lactate or incubated in culture medium. While 2 monkeys out of 5 injected with preserved tissue had successful transplants after 4 months, all the 10 monkeys injected with fresh tissue had no transplants. The size of the two surviving transplants was small. The neurons in the transplants were mainly in clusters. Many of the cells were immature and some showed early degenerative changes. Neuronal processes were restricted to the transplants and thus showed lack of morphological integration with the host tissue. Further studies are in progress to define the nature of the embryonic tissue of primate which can grow and survive and also the role of neural grafts in functional recovery following experimental lesions of the brain regions.