We thank the Rat Resource and Research Center, University of Missouri, Columbia, Missouri, for providing GFP rats; Neuralstem Inc. for providing human neural stem cells. This work was supported by the Veterans Administration, NIH (NS09881), Canadian Spinal Research Organization, The Craig H. Neilsen Foundation, and the Bernard and Anne Spitzer Charitable Trust.

All animal protocols are approved by VA-San Diego Institutional Animal Care and Use Committee (IACUC). NIH guidelines for laboratory animal care and safety are strictly followed. Animals have free access to food and water throughout the study and are adequately treated for minimizing pain and discomfort.
1. Preparation of Fibrin Components Containing Growth Factor Cocktails
<ol>
	<li>Dissolve 25 mg rat fibrinogen in 0.5 ml PBS to obtain 50 mg/ml 2x stock solution (see Materials table). Fibri...

<ol>
	<li>Ramon y Cajal, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+Degeneration+and+regeneration+of+the+nerve+system.">In Degeneration and regeneration of the nerve system.</a> , (1991).</li><li>Jakeman, L. B., Reier, P. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Axonal+projections+between+fetal+spinal+cord+transplants+and+the+adult+rat+spinal+cord:+a+neuroanatomical+tracing+study+of+local+interactions.">Axonal projections between fetal spinal cord transplants and the adult rat spinal cord: a neuroanatomical tracing study of local interactions.</a> J Comp Neurol. 307, 311-334 (1991).</li><li>Bamber, N. I., Li, H., Aebischer, P., Xu, X. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fetal+spinal+cord+tissue+in+mini-guidance+channels+promotes+longitudinal+axonal+growth+after+grafting+into+hemisected+adult+rat+spinal+cords.">Fetal spinal cord tissue in mini-guidance channels promotes longitudinal axonal growth after grafting into hemisected adult rat spinal cords.</a> Neural Plast. 6, 103-121 (1999).</li><li>Theele, D. P., Schrimsher, G. W., Reier, P. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparison+of+the+growth+and+fate+of+fetal+spinal+iso-+and+allografts+in+the+adult+rat+injured+spinal+cord.">Comparison of the growth and fate of fetal spinal iso- and allografts in the adult rat injured spinal cord.</a> Exp Neurol. 142, 128-143 (1996).</li><li>Giovanini, M. A., Reier, P. J., Eskin, T. A., Wirth, E., Anderson, D. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Characteristics+of+human+fetal+spinal+cord+grafts+in+the+adult+rat+spinal+cord:+influences+of+lesion+and+grafting+conditions.">Characteristics of human fetal spinal cord grafts in the adult rat spinal cord: influences of lesion and grafting conditions.</a> Exp Neurol. 148, 523-543 (1997).</li><li>Wictorin, K., Bj&#246;rklund, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Axon+outgrowth+from+grafts+of+human+embryonic+spinal+cord+in+the+lesioned+adult+rat+spinal+cord.">Axon outgrowth from grafts of human embryonic spinal cord in the lesioned adult rat spinal cord.</a> Neuroreport. 3, 1045-1048 (1992).</li><li>Vroemen, M., Aigner, L., Winkler, J., Weidner, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Adult+neural+progenitor+cell+grafts+survive+after+acute+spinal+cord+injury+and+integrate+along+axonal+pathways.">Adult neural progenitor cell grafts survive after acute spinal cord injury and integrate along axonal pathways.</a> Eur J Neurosci. 18, 743-751 (2003).</li><li>Blits, B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Lentiviral+vector-mediated+transduction+of+neural+progenitor+cells+before+implantation+into+injured+spinal+cord+and+brain+to+detect+their+migration,+deliver+neurotrophic+factors+and+repair+tissue.">Lentiviral vector-mediated transduction of neural progenitor cells before implantation into injured spinal cord and brain to detect their migration, deliver neurotrophic factors and repair tissue.</a> Restor Neurol Neurosci. 23, 313-324 (2005).</li><li>Lepore, A. C., Fischer, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Lineage-restricted+neural+precursors+survive,+migrate,+and+differentiate+following+transplantation+into+the+injured+adult+spinal+cord.">Lineage-restricted neural precursors survive, migrate, and differentiate following transplantation into the injured adult spinal cord.</a> Exp Neurol. 194, 230-242 (2005).</li><li>Gaillard, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reestablishment+of+damaged+adult+motor+pathways+by+grafted+embryonic+cortical+neurons.">Reestablishment of damaged adult motor pathways by grafted embryonic cortical neurons.</a> Nat Neurosci. 10, 1294-1299 (2007).</li><li>Remy, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=New+lines+of+GFP+transgenic+rats+relevant+for+regenerative+medicine+and+gene+therapy.">New lines of GFP transgenic rats relevant for regenerative medicine and gene therapy.</a> Transgenic Res. 19, 745-763 (2010).</li><li>Cao, Q. L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pluripotent+stem+cells+engrafted+into+the+normal+or+lesioned+adult+rat+spinal+cord+are+restricted+to+a+glial+lineage.">Pluripotent stem cells engrafted into the normal or lesioned adult rat spinal cord are restricted to a glial lineage.</a> Exp Neurol. 167, 48-58 (2001).</li><li>Mothe, A. J., Kulbatski, I., Parr, A., Mohareb, M., Tator, C. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Adult+spinal+cord+stem/progenitor+cells+transplanted+as+neurospheres+preferentially+differentiate+into+oligodendrocytes+in+the+adult+rat+spinal+cord.">Adult spinal cord stem/progenitor cells transplanted as neurospheres preferentially differentiate into oligodendrocytes in the adult rat spinal cord.</a> Cell Transplant. 17, 735-751 (2008).</li><li>Bryda, E. C., Pearson, M., Agca, Y., Bauer, B. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Method+for+detection+and+identification+of+multiple+chromosomal+integration+sites+in+transgenic+animals+created+with+lentivirus.">Method for detection and identification of multiple chromosomal integration sites in transgenic animals created with lentivirus.</a> Biotechniques. 41, 715-719 (2006).</li><li>Willerth, S. M., Faxel, T. E., Gottlieb, D. I., Sakiyama-Elbert, S. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+effects+of+soluble+growth+factors+on+embryonic+stem+cell+differentiation+inside+of+fibrin+scaffolds.">The effects of soluble growth factors on embryonic stem cell differentiation inside of fibrin scaffolds.</a> Stem Cells. 25, 2235-2244 (2007).</li><li>Grumbles, R. M., Sesodia, S., Wood, P. M., Thomas, C. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Neurotrophic+factors+improve+motoneuron+survival+and+function+of+muscle+reinnervated+by+embryonic+neurons.">Neurotrophic factors improve motoneuron survival and function of muscle reinnervated by embryonic neurons.</a> J Neuropathol Exp Neurol. 68, 736-746 (2009).</li><li>Kadoya, K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Combined+intrinsic+and+extrinsic+neuronal+mechanisms+facilitate+bridging+axonal+regeneration+one+year+after+spinal+cord+injury.">Combined intrinsic and extrinsic neuronal mechanisms facilitate bridging axonal regeneration one year after spinal cord injury.</a> Neuron. 64, 165-172 (2009).</li><li>Lu, P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Long-distance+growth+and+connectivity+of+neural+stem+cells+after+severe+spinal+cord+injury.">Long-distance growth and connectivity of neural stem cells after severe spinal cord injury.</a> Cell. 150, 1264-1273 (2012).</li><li>Coumans, J. V., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Axonal+regeneration+and+functional+recovery+after+complete+spinal+cord+transection+in+rats+by+delayed+treatment+with+transplants+and+neurotrophins.">Axonal regeneration and functional recovery after complete spinal cord transection in rats by delayed treatment with transplants and neurotrophins.</a> J Neurosci. 21 (23), 9334-9344 (2001).</li><li>Harris, J., Lee, H., Tu, C. T., Cribbs, D., Cotman, C., Jeon, N. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Preparing+e18+cortical+rat+neurons+for+compartmentalization+in+a+microfluidic+device.">Preparing e18 cortical rat neurons for compartmentalization in a microfluidic device.</a> J Vis Exp. (305), (2007).</li><li>Yan, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Extensive+neuronal+differentiation+of+human+neural+stem+cell+grafts+in+adult+rat+spinal+cord.">Extensive neuronal differentiation of human neural stem cell grafts in adult rat spinal cord.</a> PLoS Med. 4 (2), e39 (2007).</li><li>Popovich, P. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Building+bridges+for+spinal+cord+repair.">Building bridges for spinal cord repair.</a> Cell. 150 (6), 1105-1106 (2012).</li><li>Catelas, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fibrin.">Fibrin.</a> Comprehensive Biomaterials. 2, 303-328 (2011).</li><li>Petter-Puchner, A. H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+long-term+neurocompatibility+of+human+fibrin+sealant+and+equine+collagen+as+biomatrices+in+experimental+spinal+cord+injury.">The long-term neurocompatibility of human fibrin sealant and equine collagen as biomatrices in experimental spinal cord injury.</a> Exp Toxicol Pathol. 58, 237-245 (2007).</li><li>Gage, F. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mammalian+neural+stem+cells.">Mammalian neural stem cells.</a> Science. 287, 1433-1438 (2000).</li><li>Deister, C., Schmidt, C. 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One of the major hurdles for NSC transplantation in the injured spinal cord is poor survival in the lesion center. Any gaps or cavities in the lesion site could potentially reduce or weaken the formation of functional neuronal relays between supraspinal axons and separated spinal cord segments below the injury. In addition, poor survival of grafted NSCs may affect their integration with host tissue, and therefore reduce connectivity of grafted neurons with host neurons. Potential mechanisms to explain cell loss include t...

Spinal cord injury (SCI) often damages not only white matter tracts that carry signals to and from the brain, but also the central gray matter, causing segmental loss of interneurons and motor neurons. The consequence of SCI is loss of both motor and sensory function below the lesion. Unfortunately, the adult central nervous system (CNS) does not spontaneously regenerate, resulting in permanent functional deficits1. Therefore, reconstruction of the injured adult spinal cord and improvement in motor, sensory and autonomic function is an important goal of SCI research. Neural stem cells (NSCs), whether directly isolated from embryonic or adult CNS, are compelling candidate cells to replace lost neurons and glia. Moreover, these cells have the potential to form new functional relays to restore axonal conduction across a lesion site2,3.
To date, there has not been a detailed elucidation of the anatomical, electrophysiological and behavioral effects of neuronal relay formation by transplanted NSCs after severe SCI. There are several reasons for this: first, transplanted NSCs or fetal CNS tissue survive poorly when grafted into large lesion cavities. Previous studies show substantial early cell loss, leaving large empty cystic lesion cavities4,5. In some studies the grafted cells would subsequently divide and fill the lesion cavity4,5, but this might occur after a delay of days to weeks, and subsequent lesion site filling might not be complete or consistent. Second, an efficient tracking system that provides sound data on cellular survival, differentiation/maturation, and outgrowth of transplanted NSCs was lacking. Most early studies utilized antegrade and retrograde labeling to trace axonal projections from transplants2,3. However, these techniques only partially and often unclearly labeled axonal projections arising from grafted cells, and tracer methods are subject to artifacts caused by dye leakage beyond the implanted cells. Other groups used human specific neuronal markers to label axonal projections after transplantation of human fetal NSCs into injured rodent spinal cord5,6. However, in those studies, the xenografts did not consistently survive well. Recently, viral &#160;delivery of the GFP reporter gene was used to label cultured NSCs7,8. However, GFP expression was often inconsistent and can be down-regulated7. Recently, the use of transgenic donor mice or rats stably expressing the reporter gene, GFP, or the human placental alkaline phosphatase, has dramatically improved the tracking of transplanted neural stem cells/progenitors in vivo9,11. Third, several studies indicate that in vitro cultured rat NSCs derived from either embryonic or adult CNS exclusively differentiate into glial lineages when transplanted into the milieu of the intact or injured adult spinal cord7,12,13, despite the fact that these neural stem cells are capable of differentiating into both neurons and glia in vitro, indicating that local environments may dictate the fate of stem cells. Alternatively, cultured NSCs, especially those derived from adult CNS, may have intrinsic defaulty property to differentiate into glial lineages in vivo13.
Because of the limitations discussed above, our group recently developed a new protocol to improve embryonic NSC tracking, survival, and differentiation/maturation in the severely injured adult spinal cord. Briefly, we began with a stable transgenic Fischer 344 rat inbreed line expressing a GFP reporter gene that sustains GFP expression after in vivo transplantation14. Next, we used freshly isolated NSCs from embryonic day 14 Fischer 344 spinal cord, a stage of development that retains the potential to generate both neurons and glia. Finally, we embedded freshly dissociated NSCs into a fibrin matrix containing growth factors15-17 to retain the cells and evenly distribute them within a large lesion cavity, aiming to support graft cell survival, differentiation and integration. Grafts were placed into sites of T3 complete transection, two weeks after spinal cord injury. These grafted cells consistently filled complete transection sites and differentiated into abundant neurons that extended large numbers of axons into host spinal cord over long distances18. Similar results were obtained using cultured human neural stem cell grafts to immuno-deficient rats18.

<table border="1">
 <tbody>
 <tr>
 <td>Reagents</td>
 <td>Company</td>
 <td>Catalogue</td>
 <td>Comment</td>
 </tr>
 <tr>
 <td>Fibrinogen(rat)</td>
 <td>Sigma</td>
 <td>F6755-25MG</td>
 <td>2 hr at 37 &deg;C to dissovle 
 Stock Concentration: 50 mg/ml 
 Final Concentration: 25 mg/ml</td>
 </tr>
 <tr>
 <td>Thrombin (rat)</td>
 <td>Sigma</td>
 <td>T5772-100UN</td>
 <td>Dissovle in 10 mM CaCl2 
 Stock Concentration: 50 U/ml 
 Final Concentration: 25 mg/ml</td>
 </tr>
 <tr>
 <td>bFGF (human)</td>
 <td>Sigma</td>
 <td>F0291 (25 &mu;g)</td>
 <td>Stock Concentration: 200 ng/&mu;l 
 Final Concentration: 10 ng/&mu;l</td>
 </tr>
 <tr>
 <td>EGF (murine)</td>
 <td>Sigma</td>
 <td>E1257 (0.1 mg)</td>
 <td>Stock Concentration: 200 ng/&mu;l 
 Final Concentration: 10 ng/&mu;l</td>
 </tr>
 <tr>
 <td>BDNF(human)</td>
 <td>Peprotech</td>
 <td>452-02 (1 mg)</td>
 <td>Stock Concentration: 1000 ng/&mu;l 
 Final Concentration: 50 ng/&mu;l</td>
 </tr>
 <tr>
 <td>NT-3 (human)</td>
 <td>Peprotech</td>
 <td>452-03 (1 mg)</td>
 <td>Stock Concentration: 1000 ng/&mu;l 
 Final Concentration: 50 ng/&mu;l</td>
 </tr>
 <tr>
 <td>GDNF (rat)</td>
 <td>Sigma</td>
 <td>G1401 (10 &mu;g)</td>
 <td>Stock Concentration: 200 ng/&mu;l 
 Final Concentration: 10 ng/&mu;l</td>
 </tr>
 <tr>
 <td>IGF-1(mouse)</td>
 <td>Sigma</td>
 <td>I8779 (50 &mu;g)</td>
 <td>Stock Concentration: 200 ng/&mu;l 
 Final Concentration: 10 ng/&mu;l</td>
 </tr>
 <tr>
 <td>aFGF (human)</td>
 <td>Sigma</td>
 <td>F5542 (25 &mu;g)</td>
 <td>Stock Concentration: 200 ng/&mu;l 
 Final Concentration: 10 ng/&mu;l </td>
 </tr>
 <tr>
 <td>PDGF-AA (human)</td>
 <td>Sigma</td>
 <td>P3076 (10 &mu;g)</td>
 <td>Stock Concentration: 200 ng/&mu;l 
 Final Concentration: 10 ng/&mu;l</td>
 </tr>
 <tr>
 <td>HGF (human)</td>
 <td>Sigma</td>
 <td>H9661 (5 &mu;g)</td>
 <td>Stock Concentration: 200 ng/&mu;l 
 Final Concentration: 10 ng/&mu;l</td>
 </tr>
 <tr>
 <td>MDL28170</td>
 <td>Sigma</td>
 <td>M6690 (25 mg)</td>
 <td>Stock in DMSO 
 Stock Concentration: 1 mM 
 Final Concentration: 50 &mu;M</td>
 </tr>
 <tr>
 <td>PBS</td>
 <td>Millipore</td>
 <td>BSS-1005-B</td>
 <td>Stock Concentration: 1X 
 Final Concentration: 1X</td>
 </tr>
 <tr>
 <td>DMSO</td>
 <td>Sigma</td>
 <td>D2650</td>
 <td></td>
 </tr>
 <tr>
 <td>Ketamine</td>
 <td>Putney</td>
 <td>26637-411-01</td>
 <td>40-80 mg/kg 
 Stock Concentration: 100 mg/ml 
 Final Concentration: 25 mg/ml</td>
 </tr>
 <tr>
 <td>Xylazine</td>
 <td>Lloyd</td>
 <td>0410,</td>
 <td>2.5-8 mg/ml 
 Stock Concentration: 100 mg/ml 
 Final Concentration: 1.3 mg/ml</td>
 </tr>
 <tr>
 <td>Acepromazine</td>
 <td>Butler</td>
 <td>003845</td>
 <td>0.5-4 mg/ml 
 Stock Concentration: 10 mg/ml 
 Final Concentration: 0.25 mg/ml</td>
 </tr>
 <tr>
 <td>Betadine</td>
 <td>Healthpets</td>
 <td>BET16OZ</td>
 <td></td>
 </tr>
 <tr>
 <td>Ringers</td>
 <td>Abbott</td>
 <td>04860-04-10</td>
 <td>2-3 ml/inj</td>
 </tr>
 <tr>
 <td>Banamine</td>
 <td>Schering-Plough</td>
 <td>0061-0851-03</td>
 <td>2.5 -5 mg/kg 
 Stock Concentration: 50 mg/ml 
 Final Concentration: 0.5 mg/ml</td>
 </tr>
 <tr>
 <td>Ampicillin</td>
 <td>Sandoz</td>
 <td>0781-3404-85</td>
 <td>80-100 mg/kg 
 Final Concentration: 50 mg/ml</td>
 </tr>
 <tr>
 <td>LH-RH</td>
 <td>Sigma</td>
 <td>L4513</td>
 <td>200 &mu;g/kg 
 Final Concentration: 200 &mu;g/ml</td>
 </tr>
 <tr>
 <td>HBSS</td>
 <td>Gibco</td>
 <td>14175-096</td>
 <td></td>
 </tr>
 <tr>
 <td>Trypsin</td>
 <td>Gibco</td>
 <td>25200056 </td>
 <td>Stock Concentration: 0.25 % 
 Final Concentration: 0.125 %</td>
 </tr>
 <tr>
 <td>DMEM</td>
 <td>Gibco</td>
 <td>11995073 </td>
 <td></td>
 </tr>
 <tr>
 <td>FBS</td>
 <td>Gibco</td>
 <td>16000044 </td>
 <td>Stock Concentration: 100 % 
 Final Concentration: 10 %</td>
 </tr>
 <tr>
 <td>Neurobasal Medium</td>
 <td>Gibco</td>
 <td>21103049 </td>
 <td></td>
 </tr>
 <tr>
 <td>B27</td>
 <td>Gibco</td>
 <td>17504044</td>
 <td>Stock Concentration: 100x 
 Final Concentration: 1x</td>
 </tr>
 <td></td>
 <td></td>
 <td></td>
 <td>Note, use human reagents for grafts of human NSCs</td>
 </tbody>
</table>

promotion of survival and differentiation of neural stem cells with fibrin and growth factor cocktails after severe spinal cord injury

Neural stem cells (NSCs) can self-renew and differentiate into neurons and glia. Transplanted NSCs can replace lost neurons and glia after spinal cord injury (SCI), and can form functional relays to re-connect spinal cord segments above and below a lesion. Previous studies grafting neural stem cells have been limited by incomplete graft survival within the spinal cord lesion cavity. Further, tracking of graft cell survival, differentiation, and process extension had not been optimized. Finally, in previous studies, cultured rat NSCs were typically reported to differentiate into glia when grafted to the injured spinal cord, rather than neurons, unless fate was driven to a specific cell type. To address these issues, we developed new methods to improve the survival, integration and differentiation of NSCs to sites of even severe SCI. NSCs were freshly isolated from embryonic day 14 spinal cord (E14) from a stable transgenic Fischer 344 rat line expressing green fluorescent protein (GFP) and were embedded into a fibrin matrix containing growth factors; this formulation aimed to retain grafted cells in the lesion cavity and support cell survival. NSCs in the fibrin/growth factor cocktail were implanted two weeks after thoracic level-3 (T3) complete spinal cord transections, thereby avoiding peak periods of inflammation. Resulting grafts completely filled the lesion cavity and differentiated into both neurons, which extended axons into the host spinal cord over remarkably long distances, and glia. Grafts of cultured human NSCs expressing GFP resulted in similar findings. Thus, methods are defined for improving neural stem cell grafting, survival and analysis of in vivo findings.

GFP immunohistological labeling demonstrates that grafted rat NSCs resuspended in phosphate buffered saline (PBS) (lacking a fibrin matrix and growth factors) survived poorly in the T3 transection site, only attaching to the lesion/host margin and leaving most of the lesion site empty without grafted cells (Figure 2A). The survival of NSCs improved when co-grafted with fibrin matrices alone, but the graft did not completely fill up a large lesion cavity (data not shown). Therefore, we embedded NSCs into ...

Watch this Scientific Journal Video about Promotion of Survival and Differentiation of Neural Stem Cells with Fibrin and Growth Factor Cocktails after Severe Spinal Cord Injury at JoVE.com

Promotion of Survival and Differentiation of Neural Stem Cells with Fibrin and Growth Factor Cocktails after Severe Spinal Cord Injury

Fibrin matrices containing growth factors were used to retain grafted neural stem cells into sites of complete spinal cord transection. Grafted cells completely filled the lesion cavity and differentiated into multiple neural cell types, including neurons that extended axons into host spinal cord over long distances.

Neural stem cells (NSCs) can self-renew and differentiate into neurons and glia. Transplanted NSCs can replace lost neurons and glia after spinal cord ...

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12.3K 조회수.  Veterans Administration Medical Center, San Diego.  성장 인자를 함유하는 피브린 매트릭스는 완전한 척수 절개 부위로 그라프 신경 줄기 세포를 유지하기 위해 사용되었다. 이식 세포가 완전히 병변 캐비티를 채우고 장거리 호스트 척수로 축삭을 확장 신경 세포를 포함한 여러 신경 세포 유형으로 분화. 