Questo lavoro è stato sostenuto finanziariamente dal progetto SAF2017-82736-C2-1-R dal Ministerio de Ciencia e Innovación al MTM-F e dalla Fundación Universidad Francisco de Vitoria a JS.

NOTA: La sperimentazione animale è stata approvata dai comitati nazionali e istituzionali di bioetica.
1. cultura ihOEG (Ts12 e Ts14)
NOTA: Questa procedura viene eseguita in condizioni sterili in un armadio di biosicurezza per la coltura tissutale.
<ol><li>Preparare un supporto di coltura OEG ME10 da 50 mL come previsto nella tabella 1.</li>
	<li>Preparare 5 ml di DMEM/F12-FBS, come previsto nella tabella 1, in un tubo conico da 15 ml.</li>
	<li>Riscaldare entrambi i supporti a 37 °C in un bagno d'acqua pulita, per 15 minuti.</li>
	<li>Scongelare le fiale delle cellule Ts12 e Ts14 a 37 °C in un bagno d'acqua pulita.</li>
	<li>Resuspend e aggiungere celle al supporto di coltura DMEM/F12-FBS preparato nel passaggio 2.</li>
	<li>Centrifuga per 5 min a 200 x g.</li>
	<li>Aspira al supernatante.</li>
	<li>Aggiungere 500 μL di mezzo ME10 e rimosogliere il pellet.</li>
	<li>Preparare un piatto di coltura cellulare p60 con 3 mL di ME10 e aggiungere la sospensione cellulare, dropwise.</li>
	<li>Spostarsi per distribuire le celle in modo uniforme sulla piastra.</li>
	<li>Cellule di coltura a 37 °C nel 5% di CO2. NOTA: Dopo aver raggiunto la confluenza, deve essere fatto almeno un altro passaggio per ottimizzare le cellule per la cocoltura. È necessaria una confluenza del 90% prima di seminarli sulle copertine per la cocoltura. Un p-60 confluente ha un numero di cella medio di 7 x 105 per Ts14 e 2,5 x 106 per le linee cellulari Ts12. Le linee cellulari Ts12 e Ts14 devono essere passaggio ogni 2-3 giorni.</li>
</ol>2. Preparazione di ihOEG (Ts12 e Ts14) per il saggio
NOTA: Questo passaggio deve essere fatto 24 ore prima della dissezione rgn e della cocoltura.
<ol><li>Trattare 12 mm Ø coprelips con 10 μg/mL poli-L-lisina (PLL) per 1 h. NOTA: Le coverlips possono essere lasciate durante la notte in soluzione PLL.</li>
	<li>Lavare i copripelli con 1x soluzione salina tampone fosfato (PBS), tre volte.</li>
	<li>Staccare le cellule Ts12 e Ts14 ihOEG dal piatto di coltura cellulare p60.<ol>
<li>Aggiungere 4 ml di mezzo di coltura DMEM/F12-FBS(tabella 1)a un tubo conico da 15 ml. Riscaldare a 37 °C in un bagno d'acqua pulito.</li>
		<li>Rimuovere il mezzo dalle piastre e lavare le celle con 1 mL di 1x PBS-EDTA, una volta.</li>
		<li>Aggiungere 1 mL di tripside-EDTA alle cellule OEG e incubare per 3-5 min a 37 °C, 5% CO2.
</li>
		<li>Raccogliere le celle con una pipetta p1000 e trasferirle su un supporto preparato nel passaggio 3.1.</li>
		<li>Centrifuga per 5 min a 200 x g.</li>
		<li>Aspira al supernatante.</li>
		<li>Aggiungere 1 mL di mezzo ME10 e rimospend il pellet.</li>
		<li>Contare il numero di cellulare in un emocitometro.</li>
	</ol>
</li>
	<li>Semina 80.000 cellule Ts14 o 100.000 cellule Ts12/pozzo sui copripasci in piastre da 24 pozzi in 500 μL di mezzo ME10.</li>
	<li>Cellule di coltura a 37 °C nel 5% di CO2, per 24 h.</li>
</ol>3. Dissezione del tessuto retinale
NOTA: i ratti Wistar maschi di 2 mesi sono usati come fonte RGN. Due retine (un topo) per 20 pozzi di un piatto cellulare da 24 po '. Materiale chirurgico autoclave prima dell'uso. Il kit di dissociazione papaina viene acquistato commercialmente(Tavolo dei Materiali). Seguire le istruzioni del provider per la ricostituzione. Ricostituire L,L-2-ammino-5-acido fosfonovalerico (APV) in 5 mM e preparare le aliquote.
<ol><li>Il giorno del saggio, preparare i seguenti media.<ol>
<li>Preparare un piatto di coltura cellulare p60 con 5 mL di EBSS freddo (fiala 1 del kit di dissociazione della papaina).</li>
		<li>Preparare un piatto di coltura cellulare p60 con fiala ricostituita 2 (papaina) del kit di dissociazione della papaina più 50 μL di APV.  Aggiungere quindi 250 μL di flaconcino ricostituito 3 (DNasi più 5 μL di APV).</li>
		<li>In un mix di tubi sterili 2,7 ml di flaconcino 1 con 300 μL di flaconcino 4 (inibitore della proteasi albumina-ovomucoide). Aggiungere 150 μL di flaconcino 3 (DNasi) più 30 μL di APV.</li>
		<li>Preparare 20 mL di mezzo Neurobasal-B27 (NB-B27) come previsto nella tabella 1.</li>
	</ol>
</li>
	<li>Sacrificare un topo per asfissia con CO2.</li>
	<li>Rimuovere la testa per decapitazione con ghigliottina; posizionarlo in una piastra di Petri da 100 mm e spruzzare la testa con etanolo al 70% prima di posizionare in una cappa di flusso laminare.</li>
	<li>Tagliare i baffi del topo con le forbici in modo che non interferiscano con la manipolazione degli occhi.</li>
	<li>Afferrare il nervo ottico con pinze per estrarre il bulbo oculare abbastanza da poter fare un'incisione sull'occhio con un bisturi.</li>
	<li>Rimuovere la lente e l'umorismo vitreo ed estrarre la retina (tessuto arancione), mentre gli strati rimanenti dell'occhio rimangono all'interno (incluso lo strato epiteliale del pigmento).</li>
	<li>Posizionare la retina nel piatto di coltura cellulare p60 preparato al passaggio 3.1.1.</li>
	<li>Trasferire la retina nel piatto di coltura cellulare p60 preparato al passaggio 3.1.2 e tagliarla con il bisturi in piccoli pezzi di dimensioni approssimative < 1 mm.</li>
	<li>Trasferimento in un tubo di plastica da 15 ml.</li>
	<li>Incubare il tessuto per 30 min, in un incubatore umidificato a 37 °C sotto il 5% di CO2, con agitazione ogni 10 min.</li>
	<li>Dissociare i ciuffi cellulari tubazioni su e giù con una pipetta Pasteur in vetro.</li>
	<li>Centrifugare la sospensione cellulare a 200 x g per 5 min.</li>
	<li>Scartare il supernatante e inattivare la papaina, rimescolare il pellet cellulare nella soluzione preparata al passaggio 3.1.3. (1,5 mL per 2 occhi).</li>
	<li>Pipettare con cura questa sospensione cellulare in 5 mL di flaconcino ricostituito 4.</li>
	<li>Centrifuga a 200 x g per 5 min.</li>
	<li>Durante la centrifugazione, rimuovere completamente il mezzo ME-10 dalla piastra cellulare del pozzo OEG 24 (precedentemente preparata nel passaggio 2) e sostituirlo con 500 μL di mezzo NB-B27 per pozzo.</li>
	<li>Scartare il supernatante e rimescolare le cellule in 2 mL di mezzo NB-B27.</li>
	<li>Piastra 100 μL di sospensione cellulare retinica, per pozzo della piastra m24, su coprispalla monostrati OEG trattati con PLL.</li>
	<li>Mantenere le colture a 37 °C con il 5% di CO2 per 96 h in mezzo NB-B27.</li>
</ol>4. Immunostaining
<ol><li>Dopo 96 ore, fissare le cellule per 10 minuti aggiungendo lo stesso volume del 4% di paraformaldeide (PFA) in 1x PBS al mezzo di coltura (600 μL) (concentrazione finale PFA 2%).</li>
	<li>Rimuovere il supporto e il PFA dalla piastra a 24 poliwell e aggiungere ancora una volta 500 μL di paraformaldeide al 4% (PFA) in 1x PBS. Incubare per 10 minuti.</li>
	<li>Scartare il fissatore e lavare 3 volte con 1x PBS per 5 minuti.</li>
	<li>Blocco con 0,1% Tritone X-100/1% FBS in PBS (PBS-TS) per 30-40 min.</li>
	<li>Preparare gli anticorpi primari nel tampone PBS-TS come segue: SMI31 (contro le proteine MAP1B e NF-H) anticorpo monoclonale (1:500). 514 (riconosce le proteine MAP2A e B) antisiero policlonale coniglio (1:400).</li>
	<li>Aggiungere anticorpi primari alle coculture e incubare durante la notte a 4 °C.</li>
	<li>Il giorno dopo, scartare gli anticorpi e lavare le coverlips con 1x PBS, 3 volte, per 5 minuti.</li>
	<li>Preparare gli anticorpi secondari nel tampone PBS-TS come segue: Per SMI-31, anti-mouse Alexa Fluor 488 (1:500). Per 514, anti-coniglio Alexa-594 (1:500).</li>
	<li>Incubare le cellule con i corrispondenti anticorpi secondari fluorescenti per 1 h, a RT, al buio.</li>
	<li>Lavare i copripavimenti con 1x PBS, 3 volte, per 5 minuti, al buio.</li>
	<li>Infine, montare i copripasto con supporto di montaggio(Tavolo deiMateriali) e mantenere a 4 °C. NOTA: Quando necessario, possono essere eseguiti nuclei fluorescenti contenenti DAPI (4,6-diamidino-2-fenilindolo). Prima del montaggio, incubare le cellule per 10 minuti al buio con DAPI (10 μg/mL in 1x PBS). Lavare le coverlips 3 volte con 1x PBS e infine montare i copripavimenti con il supporto di montaggio.</li>
</ol>5. Quantificazione della rigenerazione assionale
NOTA: I campioni sono quantificati nell'obiettivo 40x di un microscopio a epifluorescenza. Un minimo di 30 immagini dovrebbero essere scattate su campi casuali, con almeno 200 neuroni, da quantificare per ogni trattamento. Ogni esperimento deve essere ripetuto almeno tre volte.
<ol><li>Quantificare la percentuale di neuroni con assone (neurite positiva SMI31) rispetto alla popolazione totale di RGN (identificata con MAP2A/B 514 immunostaining positivo del corpo neuronale e dei dendriti).</li>
	<li>Quantificare l'indice di rigenerazione assonale o la lunghezza assionale media (μm/neurone). Questo parametro è definito come la somma delle lunghezze (in μm) di tutti gli assoni identificati, divisi per il numero totale di neuroni contati, indipendentemente dal fatto che presentavano o meno un assone. La lunghezza assonale è determinata utilizzando il plugin NeuronJ del software di immagini ImageJ (NIH-USA).</li>
	<li>Calcola la media, la deviazione standard e la significatività statistica utilizzando il software appropriato.</li>
</ol>

<ol>
	<li>Kanno, H., Pearse, D. D., Ozawa, H., Itoi, E., Bunge, M. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Schwann+cell+transplantation+for+spinal+cord+injury+repair:+Its+significant+therapeutic+potential+and+prospectus.">Schwann cell transplantation for spinal cord injury repair: Its significant therapeutic potential and prospectus.</a> Reviews in the Neurosciences. 26 (2), 121-128 (2015).</li><li>Assinck, P., Duncan, G. J., Hilton, B. J., Plemel, J. R., Tetzlaff, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cell+transplantation+therapy+for+spinal+cord+injury.">Cell transplantation therapy for spinal cord injury.</a> Nature Neuroscience. 20 (5), 637-647 (2017).</li><li>Lindsay, S. L., Toft, A., Griffin, J., Emraja, A. M. M., Barnett, S. C., Riddell, J. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Human+olfactory+mesenchymal+stromal+cell+transplants+promote+remyelination+and+earlier+improvement+in+gait+coordination+after+spinal+cord+injury.">Human olfactory mesenchymal stromal cell transplants promote remyelination and earlier improvement in gait coordination after spinal cord injury.</a> Glia. 65 (4), 639-656 (2017).</li><li>Moreno-Flores, M. T., 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=A+clonal+cell+line+from+immortalized+olfactory+ensheathing+glia+promotes+functional+recovery+in+the+injured+spinal+cord.">A clonal cell line from immortalized olfactory ensheathing glia promotes functional recovery in the injured spinal cord.</a> Molecular Therapy. 13 (3), 598-608 (2006).</li><li>Gilmour, A. D., Reshamwala, R., Wright, A. A., Ekberg, J. A. K., St. John, J. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Optimizing+olfactory+ensheathing+cell+transplantation+for+spinal+cord+injury+repair.">Optimizing olfactory ensheathing cell transplantation for spinal cord injury repair.</a> Journal of Neurotrauma. 37 (5), 817-829 (2020).</li><li>Barraud, 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=Neural+crest+origin+of+olfactory+ensheathing+glia.">Neural crest origin of olfactory ensheathing glia.</a> Proceedings of the National Academy of Sciences of the United States of America. 107, 21040-21045 (2010).</li><li>Su, Z., He, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Olfactory+ensheathing+cells:+biology+in+neural+development+and+regeneration.">Olfactory ensheathing cells: biology in neural development and regeneration.</a> Progress in Neurobiology. 92 (4), 517-532 (2010).</li><li>Yao, R., 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=Olfactory+ensheathing+cells+for+spinal+cord+injury:+sniffing+out+the+issues.">Olfactory ensheathing cells for spinal cord injury: sniffing out the issues.</a> Cell Transplant. 27 (6), 879-889 (2018).</li><li>G&#243;mez, R. M., 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=Cell+therapy+for+spinal+cord+injury+with+olfactory+ensheathing+glia+cells+(OECs).">Cell therapy for spinal cord injury with olfactory ensheathing glia cells (OECs).</a> Glia. 66 (7), 1267-1301 (2018).</li><li>Plant, G. W., Harvey, A. R., Leaver, S. G., Lee, S. V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Olfactory+ensheathing+glia:+repairing+injury+to+the+mammalian+visual+system.">Olfactory ensheathing glia: repairing injury to the mammalian visual system.</a> Experimental Neurology. 229 (1), 99-108 (2011).</li><li>Xue, 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=Transplanted+olfactory+ensheathing+cells+restore+retinal+function+in+a+rat+model+of+light-induced+retinal+damage+by+inhibiting+oxidative+stress.">Transplanted olfactory ensheathing cells restore retinal function in a rat model of light-induced retinal damage by inhibiting oxidative stress.</a> Oncotarget. 8 (54), 93087-93102 (2017).</li><li>Pastrana, E., 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=Genes+associated+with+adult+axon+regeneration+promoted+by+olfactory+ensheathing+cells:+a+new+role+for+matrix+metalloproteinase+2.">Genes associated with adult axon regeneration promoted by olfactory ensheathing cells: a new role for matrix metalloproteinase 2.</a> The Journal of Neuroscience. 26, 5347-5359 (2006).</li><li>Pastrana, E., 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=BDNF+production+by+olfactory+ensheathing+cells+contributes+to+axonal+regeneration+of+cultured+adult+CNS+neurons.">BDNF production by olfactory ensheathing cells contributes to axonal regeneration of cultured adult CNS neurons.</a> Neurochemistry International. 50, 491-498 (2007).</li><li>Sim&#243;n, D., 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=Expression+of+plasminogen+activator+inhibitor-1+by+olfactory+ensheathing+glia+promotes+axonal+regeneration.">Expression of plasminogen activator inhibitor-1 by olfactory ensheathing glia promotes axonal regeneration.</a> Glia. 59, 1458-1471 (2011).</li><li>Lim, F., 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=Reversibly+immortalized+human+olfactory+ensheathing+glia+from+an+elderly+donor+maintain+neuroregenerative+capacity.">Reversibly immortalized human olfactory ensheathing glia from an elderly donor maintain neuroregenerative capacity.</a> Glia. 58, 546-558 (2010).</li><li>Garc&#237;a-Escudero, 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=Prevention+of+senescence+progression+in+reversibly+immortalized+human+ensheathing+glia+permits+their+survival+after+deimmortalization.">Prevention of senescence progression in reversibly immortalized human ensheathing glia permits their survival after deimmortalization.</a> Molecular Therapy. 18, 394-403 (2010).</li><li>Garc&#237;a-Escudero, 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=A+neuroregenerative+human+ensheathing+glia+cell+line+with+conditional+rapid+growth.">A neuroregenerative human ensheathing glia cell line with conditional rapid growth.</a> Cell Transplant. 20, 153-166 (2011).</li><li>Plaza, N., Sim&#243;n, D., Sierra, J., Moreno-Flores, M. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Transduction+of+an+immortalized+olfactory+ensheathing+glia+cell+line+with+the+green+fluorescent+protein+(GFP)+gene:+Evaluation+of+its+neuroregenerative+capacity+as+a+proof+of+concept.">Transduction of an immortalized olfactory ensheathing glia cell line with the green fluorescent protein (GFP) gene: Evaluation of its neuroregenerative capacity as a proof of concept.</a> Neuroscience Letters. 612, 25-31 (2016).</li><li>Deumens, R., 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=Alignment+of+glial+cells+stimulates+directional+neurite+growth+of+CNS+neurons+in+vitro.">Alignment of glial cells stimulates directional neurite growth of CNS neurons in vitro.</a> Neuroscience. 125 (3), 591-604 (2004).</li><li>Chung, R. 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=Olfactory+ensheathing+cells+promote+neurite+sprouting+of+injured+axons+in+vitro+by+direct+cellular+contact+and+secretion+of+soluble+factors.">Olfactory ensheathing cells promote neurite sprouting of injured axons in vitro by direct cellular contact and secretion of soluble factors.</a> Cell and Molecular Life Sciences. 61 (10), 1238-1245 (2004).</li><li>Leaver, S. G., Harvey, A. R., Plant, G. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Adult+olfactory+ensheathing+glia+promote+the+long-distance+growth+of+adult+retinal+ganglion+cell+neurites+in+vitro.">Adult olfactory ensheathing glia promote the long-distance growth of adult retinal ganglion cell neurites in vitro.</a> Glia. 53 (5), 467-476 (2006).</li><li>Pellitteri, R., Spatuzza, M., Russo, A., Stanzani, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Olfactory+ensheathing+cells+exert+a+trophic+effect+on+the+hypothalamic+neurons+in+vitro.">Olfactory ensheathing cells exert a trophic effect on the hypothalamic neurons in vitro.</a> Neuroscience Letters. 417 (1), 24-29 (2007).</li><li>Pellitteri, R., Spatuzza, M., Russo, A., Zaccheo, D., Stanzani, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Olfactory+ensheathing+cells+represent+an+optimal+substrate+for+hippocampal+neurons:+an+in+vitro+study.">Olfactory ensheathing cells represent an optimal substrate for hippocampal neurons: an in vitro study.</a> International Journal of Developmental Neuroscience. 27 (5), 453-458 (2009).</li><li>Runyan, S. A., Phelps, P. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mouse+olfactory+ensheathing+glia+enhance+axon+outgrowth+on+a+myelin+substrate+in+vitro.">Mouse olfactory ensheathing glia enhance axon outgrowth on a myelin substrate in vitro.</a> Experimental Neurology. 216 (1), 95-104 (2009).</li><li>Witheford, M., Westendorf, K., Roskams, A. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Olfactory+ensheathing+cells+promote+corticospinal+axonal+outgrowth+by+a+L1+CAM-dependent+mechanism.">Olfactory ensheathing cells promote corticospinal axonal outgrowth by a L1 CAM-dependent mechanism.</a> Glia. 61 (11), 1873-1889 (2013).</li><li>Roloff, F., Ziege, S., Baumg&#228;rtner, W., Wewetzer, K., Bicker, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Schwann+cell-free+adult+canine+olfactory+ensheathing+cell+preparations+from+olfactory+bulb+and+mucosa+display+differential+migratory+and+neurite+growth-promoting+properties+in+vitro.">Schwann cell-free adult canine olfactory ensheathing cell preparations from olfactory bulb and mucosa display differential migratory and neurite growth-promoting properties in vitro.</a> BMC Neuroscience. 14, 141 (2013).</li><li>Khankan, R. R., Wanner, I. B., Phelps, P. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Olfactory+ensheathing+cell-neurite+alignment+enhances+neurite+outgrowth+in+scar-like+cultures.">Olfactory ensheathing cell-neurite alignment enhances neurite outgrowth in scar-like cultures.</a> Experimental Neurology. 269, 93-101 (2015).</li><li>Wigley, C. B., Berry, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Regeneration+of+adult+rat+retinal+ganglion+cell+processes+in+monolayer+culture:+comparisons+between+cultures+of+adult+and+neonatal+neurons.">Regeneration of adult rat retinal ganglion cell processes in monolayer culture: comparisons between cultures of adult and neonatal neurons.</a> Brain Research. 470 (1), 85-98 (1988).</li><li>Sonigra, R. J., Brighton, P. C., Jacoby, J., Hall, S., Wigley, C. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Adult+rat+olfactory+nerve+ensheathing+cells+are+effective+promoters+of+adult+central+nervous+system+neurite+outgrowth+in+coculture.">Adult rat olfactory nerve ensheathing cells are effective promoters of adult central nervous system neurite outgrowth in coculture.</a> Glia. 25 (3), 256-269 (1999).</li><li>Hayat, S., Thomas, A., Afshar, F., Sonigra, R., Wigley, C. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Manipulation+of+olfactory+ensheathing+cell+signaling+mechanisms:+effects+on+their+support+for+neurite+regrowth+from+adult+CNS+neurons+in+coculture.">Manipulation of olfactory ensheathing cell signaling mechanisms: effects on their support for neurite regrowth from adult CNS neurons in coculture.</a> Glia. 44 (3), 232-241 (2003).</li><li>Kumar, R., Hayat, S., Felts, P., Bunting, S., Wigley, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Functional+differences+and+interactions+between+phenotypic+subpopulations+of+olfactory+ensheathing+cells+in+promoting+CNS+axonal+regeneration.">Functional differences and interactions between phenotypic subpopulations of olfactory ensheathing cells in promoting CNS axonal regeneration.</a> Glia. 50 (1), 12-20 (2005).</li><li>Moreno-Flores, M. T., Lim, F., Mart&#237;n-Bermejo, M. J., D&#237;az-Nido, J., Avila, J., Wandosell, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Immortalized+olfactory+ensheathing+glia+promote+axonal+regeneration+of+rat+retinal+ganglion+neurons.">Immortalized olfactory ensheathing glia promote axonal regeneration of rat retinal ganglion neurons.</a> Journal of Neurochemistry. 85 (4), 861-871 (2003).</li><li>Garc&#237;a-Escudero, 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=Patient-derived+olfactory+mucosa+cells+but+not+lung+or+skin+fibroblasts+mediate+axonal+regeneration+of+retinal+ganglion+neurons.">Patient-derived olfactory mucosa cells but not lung or skin fibroblasts mediate axonal regeneration of retinal ganglion neurons.</a> Neuroscience Letters. 509 (1), 27-32 (2012).</li><li>Sternberger, L. A., Sternberger, N. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Monoclonal+antibodies+distinguish+phosphorylated+and+nonphosphorylated+forms+of+neurofilaments+in+situ.">Monoclonal antibodies distinguish phosphorylated and nonphosphorylated forms of neurofilaments in situ.</a> Proceedings of the National Academy of Sciences of the United States of America. 80 (19), 6126-6130 (1983).</li><li>S&#225;nchez Martin, C., D&#237;az-Nido, J., Avila, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Regulation+of+a+site-specific+phosphorylation+of+the+microtubule-associated+protein+2+during+the+development+of+cultured+neurons.">Regulation of a site-specific phosphorylation of the microtubule-associated protein 2 during the development of cultured neurons.</a> Neuroscience. 87 (4), 861-870 (1998).</li><li>Reshamwala, R., Shah, M., Belt, L., Ekberg, J. A. K., St. John, J. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reliable+cell+purification+and+determination+of+cell+purity:+crucial+aspects+of+olfactory+ensheathing+cell+transplantation+for+spinal+cord+repair.">Reliable cell purification and determination of cell purity: crucial aspects of olfactory ensheathing cell transplantation for spinal cord repair.</a> Neural Regeneration Research. 15 (11), 2016-2026 (2020).</li></ol>

Gli autori non hanno nulla da rivelare.

Il trapianto OEG nei siti di lesione del SNC è considerato una terapia promettente per la lesione del SNC a causa delle sue proprietà pro-neuroregenerative costitutive7,8,9. Tuttavia, a seconda della sorgente tissutale — mucosa olfattiva (OM-OEG) rispetto al bulbo olfattivo (OB-OEG) — o dell'età del donatore, esistono notevoli variazioni in talecapacità 26,31<sup...

I neuroni del sistema nervoso centrale adulto (SNC) hanno una capacità rigenerativa limitata dopo lesioni o malattie. Una strategia comune per promuovere la rigenerazione del SNC è il trapianto, nel sito delle lesioni, di tipi cellulari che inducono la crescita assonale come cellule staminali, cellule di Schwann, astrociti o cellule olfattive glia (OEG)1,2,3,4,5.
OEG deriva dalla cresta neurale6 e si trova nella mucosa olfattiva e nel bulbo olfattivo. Nell'adulto, i neuroni sensoriali olfattivi muoiono regolarmente a causa dell'esposizione ambientale e vengono sostituiti da neuroni appena differenziati. OEG circonda e guida questi nuovi assoni olfattivi per entrare nel bulbo olfattivo e stabilire nuove sinapsi con i loro obiettivi nel CNS7. A causa di questi attributi fisiologici, l'OEG è stato utilizzato in modelli di lesione del SNC come midollo spinale o lesione del nervo ottico e le sue proprietà neuroregenerative e neuroprotettivediventano dimostrate 8,9,10,11. Diversi fattori sono stati identificati come responsabili delle caratteristiche pro-rigenerative di queste cellule, tra cui la produzione o la secrezione di fattori di crescita neurotrofica e assonale12,13,14.
Date le limitazioni tecniche per espandere le cellule OEG primarie, abbiamo precedentemente stabilito e caratterizzato linee clonali OEG umane immortalate reversibili (ihOEG), che forniscono una fornitura illimitata di OEG omogeneo. Queste cellule ihOEG derivano da colture primarie, preparate da bulbi olfattivi ottenuti in autopsie. Sono stati immortalati per trasduzione della subunità catalitica telomerasi (TERT) e dell'oncogene Bmi-1 e modificati con il virus SV40 grande antigene T15,16,17,18. Due di queste linee cellulari ihOEG sono Ts14, che mantiene la capacità rigenerativa delle colture originali e Ts12, una linea rigenerativa bassa che viene utilizzata come basso controllo di rigenerazione in questi esperimenti18.
Per valutare la capacità dell'OEG di favorire la rigenerazione assonale dopo la lesione neurale, sono stati implementati diversi modelli in vitro. In questi modelli, l'OEG viene applicato a colture di diversa origine neuronale e vengono saggiate la formazione e l'allungamento della neurite, in risposta alla cocoltura gliale. Esempi di tali fonti neuronali sono i neuroni corticali del ratto neonatale19, le ferite da graffio eseguite sui neuroni embrionali del ratto dal tessutocorticale 20,le espianto retinichedel ratto 21, i neuroni postnatali ipotalamici o ippocampali del ratto22,23, neuroni ganglionali della radice dorsale del ratto postnatale24, neuroni del tratto corticospinale del topo postnatale25,neuroni NT2umani 26o neuroni corticali cerebrali postnatali su colture reattive simili a cicatrici astrociti27.
In questi modelli, tuttavia, il test di rigenerazione si basa su neuroni embrionali o postnatali, che hanno una plasticità intrinseca che è assente nei neuroni adulti feriti. Per superare questo inconveniente, presentiamo un modello di rigenerazione assonale adulta in coculture di linee OEG con neuroni ganglionali retini adulti (RGN), basato su quello originariamente sviluppatoda Wigley etal. In breve, il tessuto retinale viene estratto da ratti adulti e digerito con papaina. La sospensione cellulare retinica viene quindi placcata su coverlips trattate con polilisina o su monostrati Ts14 e Ts12. Le colture vengono mantenute per 96 ore prima di essere fissate e quindi viene eseguita l'immunofluorescenza per i marcatori assonale (proteine MAP1B e NF-H)34 e somatodendritica (MAP2A e B)35 marcatori. La rigenerazione assonale è quantificata come percentuale di neuroni con assone, rispetto alla popolazione totale di RGN e l'indice di rigenerazione assonale è calcolato come lunghezza assonale media per neurone. Questo protocollo non è solo utile per valutare il potenziale neuroregenerativo di ihOEG, ma può essere esteso a diverse fonti di OEG o altre cellule gliali.

<table>
	<tbody>
		<tr>
			<td>antibody 514</td>
			<td>Reference 34</td>
			<td></td>
			<td>Rabbit polyclonal antiserum, which recognizes MAP2A and B.</td>
		</tr>
		<tr>
			<td>antibody SMI-31</td>
			<td>BioLegend</td>
			<td>801601</td>
			<td>Monoclonal antibody against MAP1B and NF-H proteins</td>
		</tr>
		<tr>
			<td>anti-mouse Alexa Fluor 488 antibody</td>
			<td>ThermoFisher</td>
			<td>A-21202</td>
			<td></td>
		</tr>
		<tr>
			<td>anti-rabbit Alexa Fluor 594 antibody</td>
			<td>ThermoFisher</td>
			<td>A-21207</td>
			<td></td>
		</tr>
		<tr>
			<td>B-27 Supplement</td>
			<td>Gibco</td>
			<td>17504044</td>
			<td></td>
		</tr>
		<tr>
			<td>D,L-2-amino-5-phosphonovaleric acid</td>
			<td>Sigma</td>
			<td>283967</td>
			<td>NMDA receptor inhibitor</td>
		</tr>
		<tr>
			<td>DAPI</td>
			<td>Sigma</td>
			<td>D9542</td>
			<td>Nuclei fluorescent stain</td>
		</tr>
		<tr>
			<td>DMEM-F12</td>
			<td>Gibco</td>
			<td>11320033</td>
			<td>Cell culture medium</td>
		</tr>
		<tr>
			<td>FBS</td>
			<td>Gibco</td>
			<td>11573397</td>
			<td>Fetal bovine serum</td>
		</tr>
		<tr>
			<td>FBS-Hyclone</td>
			<td>Fisher Scientific</td>
			<td>16291082</td>
			<td>Fetal bovine serum</td>
		</tr>
		<tr>
			<td>Fluoromount</td>
			<td>Southern Biotech</td>
			<td>0100-01</td>
			<td>Mounting medium</td>
		</tr>
		<tr>
			<td>ImageJ</td>
			<td>National Institutes of Health (NIH-USA)</td>
			<td></td>
			<td>Image software</td>
		</tr>
		<tr>
			<td>L-Glutamine</td>
			<td>Lonza</td>
			<td>BE17-605F</td>
			<td></td>
		</tr>
		<tr>
			<td>Neurobasal Medium</td>
			<td>Gibco</td>
			<td>21103049</td>
			<td>Neuronal cells culture medium</td>
		</tr>
		<tr>
			<td>Papain Dissociation System</td>
			<td>Worthington Biochemical Corporation</td>
			<td>LK003150</td>
			<td>For use in neural cell isolation</td>
		</tr>
		<tr>
			<td>PBS</td>
			<td>Home made</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>PBS-EDTA</td>
			<td>Lonza</td>
			<td>H3BE02-017F</td>
			<td></td>
		</tr>
		<tr>
			<td>Penicillin/Streptomycin/Amphotericin B</td>
			<td>Lonza</td>
			<td>17-745E</td>
			<td>Bacteriostatic and bactericidal</td>
		</tr>
		<tr>
			<td>Pituitary extract</td>
			<td>Gibco</td>
			<td>13028014</td>
			<td>Bovine pituitary extract</td>
		</tr>
		<tr>
			<td>Poly -L- lysine (PLL)</td>
			<td>Sigma</td>
			<td>A-003-M</td>
			<td></td>
		</tr>
	</tbody>
</table>

coculture of axotomized rat retinal ganglion neurons with olfactory ensheathing glia, as an in vitro model of adult axonal regeneration

Le cellule olfattive di glia ensheathing (OEG) sono localizzate dalla mucosa olfattiva a e nello strato nervoso olfattivo (ONL) del bulbo olfattivo. Per tutta la vita adulta, sono fondamentali per la crescita assonale dei neuroni olfattivi appena generati, dalla lamina propria all'ONL. A causa delle loro proprietà pro-rigenerative, queste cellule sono state utilizzate per favorire la rigenerazione assonale nel midollo spinale o nei modelli di lesione del nervo ottico.
Presentiamo un modello in vitro per testare e misurare la capacità neuroregenerativa OEG dopo la lesione neurale. In questo modello, l'OEG umano reversibilmente immortalato (ihOEG) è coltivato come monostrato, le retine vengono estratte da ratti adulti e i neuroni ganglionari retinali (RGN) sono coculati sul monostrato OEG. Dopo 96 ore, i marcatori assonali e somatodendritici nelle RGN vengono analizzati per immunofluorescenza e il numero di RGN con assone e la lunghezza assionale media / neurone vengono quantificati.
Questo protocollo ha il vantaggio rispetto ad altri saggi in vitro che si basano su neuroni embrionali o postnatali, che valuta le proprietà neuroregenerative OEG nel tessuto adulto. Inoltre, non è solo utile per valutare il potenziale neuroregenerativo di ihOEG, ma può essere esteso a diverse fonti di OEG o altre cellule gliali.

In questo protocollo, presentiamo un modello in vitro per testare la capacità neuroregenerativa OEG dopo la lesione neuronale. Come mostrato nella Figura 1, la sorgente OEG è una linea cellulare clonale OEG immortalata reversibile -Ts14 e Ts12-, che deriva da colture primarie, preparate da bulbi olfattivi ottenuti in autopsie15,17,18. Il tessuto retinale viene estratto da ratti adulti, digerito e ...

Watch this Scientific Journal Video about Coculture of Axotomized Rat Retinal Ganglion Neurons with Olfactory Ensheathing Glia, as an In Vitro Model of Adult Axonal Regeneration at JoVE.com

Coculture of Axotomized Rat Retinal Ganglion Neurons with Olfactory Ensheathing Glia, as an In Vitro Model of Adult Axonal Regeneration

Presentiamo un modello in vitro per valutare la capacità neuroregenerativa olfattiva di glia (OEG), dopo la lesione neurale. Si basa su una cocultura di neuroni ganglionali della retina adulta assotomizzati (RGN) su monostrati OEG e sul successivo studio della rigenerazione assonale, analizzando marcatori assonali e somatodendritici RGN.

Cocultura di neuroni ganglionali retini di ratto axotomizzati con glia ensheathing olfattiva, come modello in vitro di rigenerazione assionale adulta

Olfactory ensheathing glia (OEG) cells are localized all the way from the olfactory mucosa to and into the olfactory nerve layer (ONL) of the olfactory ...

coculture-axotomized-rat-retinal-ganglion-neurons-with-olfactory

Research

JoVE Journal

Neuroscience

3.8K Views.  Universidad Francisco de Vitoria. Presentiamo un modello in vitro per valutare la capacità neuroregenerativa olfattiva di glia (OEG), dopo la lesione neurale. Si basa su una cocultura di neuroni ganglionali della retina adulta assotomizzati (RGN) su monostrati OEG e sul successivo studio della rigenerazione assonale, analizzando marcatori assonali e somatodendritici RGN.

Video: Coculture of Axotomized Rat Retinal Ganglion Neurons with Olfactory Ensheathing Glia, as an In Vitro Model of Adult Axonal Regeneration

Bilaminar Co-culture of Primary Rat Cortical Neurons and Glia

This video will guide you through the process of culturing rat cortical neurons in the presence of a glial feeder layer, a system known as a bilaminar or co-culture model. This system is suitable for a variety of experimental needs requiring either a glass or plastic growth substrate and can also be used for culture of other types of neurons.
Rat cortical neurons obtained from the late embryonic stage (E17) are plated on glass coverslips or tissue culture dishes facing a feeder layer of glia grown on dishes or plastic coverslips (known as Thermanox), respectively. The choice between the two configurations depends on the specific experimental technique used, which may require, or not, that neurons are grown on glass (e.g. calcium imaging versus Western blot). The glial feeder layer, an astroglia-enriched secondary culture of mixed glia, is separately prepared from the cortices of newborn rat pups (P2-4) prior to the neuronal dissection.
A major advantage of this culture system as compared to a culture of neurons only is the support of neuronal growth, survival, and differentiation provided by trophic factors secreted from the glial feeder layer, which more accurately resembles the brain environment in vivo. Furthermore, the co-culture can be used to study neuronal-glial interactions1.
At the same time, glia contamination in the neuronal layer is prevented by different means (low density culture, addition of mitotic inhibitors, lack of serum and use of optimized culture medium) leading to a virtually pure neuronal layer, comparable to other established methods1-3. Neurons can be easily separated from the glial layer at any time during culture and used for different experimental applications ranging from electrophysiology4, cellular and molecular biology5-8, biochemistry5, imaging and microscopy4,6,7,9,10. The primary neurons extend axons and dendrites to form functional synapses11, a process which is not observed in neuronal cell lines, although some cell lines do extend processes.
A detailed protocol of culturing rat hippocampal neurons using this co-culture system has been described previously4,12,13. Here we detail a modified protocol suited for cortical neurons. As approximately 20x106 cells are recovered from each rat embryo, this method is particularly useful for experiments requiring large numbers of neurons (but not concerned about a highly homogenous neuronal population). The preparation of neurons and glia needs to be planned in a time-specific manner. We will provide the step-by-step protocol for culturing rat cortical neurons as well as culturing glial cells to support the neurons.

Here we provide a protocol for culturing rat cortical neurons in the presence of a glial feeder layer. The cultured neurons establish polarity and create synapses, and can be separated from the glia for use in various applications, such as electrophysiology, calcium imaging, cell survival assays, immunocytochemistry, and RNA/DNA/protein isolation.

Bilaminar co-coltura di neuroni corticali primari di ratto e Glia

This video will guide you through the process of culturing rat cortical neurons in the presence of a glial feeder layer, a system known as a bilaminar or ...

Ricerca

Neuroscienze

Selective Viral Transduction of Adult-born Olfactory Neurons for Chronic in vivo Optogenetic Stimulation

Local interneurons are continuously regenerated in the olfactory bulb of adult rodents1-3. In this process, called adult neurogenesis, neural stem cells in the walls of the lateral ventricle give rise to neuroblasts that migrate for several millimeters along the rostral migratory stream (RMS) to reach and incorporate into the olfactory bulb. To study the different steps and the impact of adult-born neuron integration into preexisting olfactory circuits, it is necessary to selectively label and manipulate the activity of this specific population of neurons. The recent development of optogenetic technologies offers the opportunity to use light to precisely activate this specific cohort of neurons without affecting surrounding neurons4,5. Here, we present a series of procedures to virally express Channelrhodopsin2(ChR2)-YFP in a temporally restricted cohort of neuroblasts in the RMS before they reach the olfactory bulb and become adult-born neurons. In addition, we show how to implant and calibrate a miniature LED for chronic in vivo stimulation of ChR2-expressing neurons.

Selective Viral Transduction of Adult-born Olfactory Neurons for Chronic in vivo Optogenetic Stimulation

Adult-born neurons of the olfactory bulb can be optogenetically controlled using Channelrhodopsin2-expressing lentiviral injection in the rostral migratory stream and chronic photostimulation with an implanted miniature LED.

Selettiva trasduzione virale di neuroni olfattivi per adulti nati per cronica In vivo Optogenetic Stimolazione

Local interneurons are continuously regenerated in the olfactory bulb of adult rodents1-3. In this process, called adult neurogenesis, neural stem cells ...

Genetic Study of Axon Regeneration with Cultured Adult Dorsal Root Ganglion Neurons

It is well known that mature neurons in the central nervous system (CNS) cannot regenerate their axons after injuries due to diminished intrinsic ability to support axon growth and a hostile environment in the mature CNS1,2. In contrast, mature neurons in the peripheral nervous system (PNS) regenerate readily after injuries3. Adult dorsal root ganglion (DRG) neurons are well known to regenerate robustly after peripheral nerve injuries. Each DRG neuron grows one axon from the cell soma, which branches into two axonal branches: a peripheral branch innervating peripheral targets and a central branch extending into the spinal cord. Injury of the DRG peripheral axons results in substantial axon regeneration, whereas central axons in the spinal cord regenerate poorly after the injury. However, if the peripheral axonal injury occurs prior to the spinal cord injury (a process called the conditioning lesion), regeneration of central axons is greatly improved4. Moreover, the central axons of DRG neurons share the same hostile environment as descending corticospinal axons in the spinal cord. Together, it is hypothesized that the molecular mechanisms controlling axon regeneration of adult DRG neurons can be harnessed to enhance CNS axon regeneration. As a result, adult DRG neurons are now widely used as a model system to study regenerative axon growth5-7.
Here we describe a method of adult DRG neuron culture that can be used for genetic study of axon regeneration in vitro. In this model adult DRG neurons are genetically manipulated via electroporation-mediated gene transfection6,8. By transfecting neurons with DNA plasmid or si/shRNA, this approach enables both gain- and loss-of-function experiments to investigate the role of any gene-of-interest in axon growth from adult DRG neurons. When neurons are transfected with si/shRNA, the targeted endogenous protein is usually depleted after 3-4 days in culture, during which time robust axon growth has already occurred, making the loss-of-function studies less effective. To solve this problem, the method described here includes a re-suspension and re-plating step after transfection, which allows axons to re-grow from neurons in the absence of the targeted protein. Finally, we provide an example of using this in vitro model to study the role of an axon regeneration-associated gene, c-Jun, in mediating axon growth from adult DRG neurons9.

An in vitro model for genetic study of axon regeneration using cultured adult mouse dorsal root ganglion neurons is described. The method includes a re-suspension/re-plating step to allow axon re-growth from neurons undergoing genetic manipulation. This approach is especially useful for loss-of-function studies of axon regeneration using RNAi-based protein knockdown.

Studio genetico della rigenerazione assonale con colture di neuroni adulti Root dorsali gangliari

It is well known that mature neurons in the central nervous system (CNS) cannot regenerate their axons after injuries due to diminished intrinsic ability ...

Transplantation of Olfactory Ensheathing Cells to Evaluate Functional Recovery after Peripheral Nerve Injury

Olfactory ensheathing cells (OECs) are neural crest cells which allow growth and regrowth of the primary olfactory neurons. Indeed, the primary olfactory system is characterized by its ability to give rise to new neurons even in adult animals. This particular ability is partly due to the presence of OECs which create a favorable microenvironment for neurogenesis. This property of OECs has been used for cellular transplantation such as in spinal cord injury models. Although the peripheral nervous system has a greater capacity to regenerate after nerve injury than the central nervous system, complete sections induce misrouting during axonal regrowth in particular after facial of laryngeal nerve transection. Specifically, full sectioning of the recurrent laryngeal nerve (RLN) induces aberrant axonal regrowth resulting in synkinesis of the vocal cords. In this specific model, we showed that OECs transplantation efficiently increases axonal regrowth.
OECs are constituted of several subpopulations present in both the olfactory mucosa (OM-OECs) and the olfactory bulbs (OB-OECs). We present here a model of cellular transplantation based on the use of these different subpopulations of OECs in a RLN injury model. Using this paradigm, primary cultures of OB-OECs and OM-OECs were transplanted in Matrigel after section and anastomosis of the RLN. Two months after surgery, we evaluated transplanted animals by complementary analyses based on videolaryngoscopy, electromyography (EMG), and histological studies. First, videolaryngoscopy allowed us to evaluate laryngeal functions, in particular muscular cocontractions phenomena. Then, EMG analyses demonstrated richness and synchronization of muscular activities. Finally, histological studies based on toluidine blue staining allowed the quantification of the number and profile of myelinated fibers.
All together, we describe here how to isolate, culture, identify and transplant OECs from OM and OB after RLN section-anastomosis and how to evaluate and analyze the efficiency of these transplanted cells on axonal regrowth and laryngeal functions.

Olfactory ensheathing cells (OECs) are neural crest cells which allow growth of the primary olfactory neurons. This specific property can be used for cellular transplantation. We present here a model of cellular transplantation based on the use of OECs in a laryngeal nerve injury model.

Il trapianto di cellule olfattive ensheathing per valutare il recupero funzionale dopo Peripheral Nerve Injury

Olfactory ensheathing cells (OECs) are neural crest cells which allow growth and regrowth of the primary olfactory neurons. Indeed, the primary olfactory ...

An In-vitro Preparation of Isolated Enteric Neurons and Glia from the Myenteric Plexus of the Adult Mouse

The enteric nervous system is a vast network of neurons and glia running the length of the gastrointestinal tract that functionally controls gastrointestinal motility. A procedure for the isolation and culture of a mixed population of neurons and glia from the myenteric plexus is described. The primary cultures can be maintained for over 7 days, with connections developing among the neurons and glia. The longitudinal muscle strip with the attached myenteric plexus is stripped from the underlying circular muscle of the mouse ileum or colon and subjected to enzymatic digestion. In sterile conditions, the isolated neuronal and glia population are preserved within the pellet following centrifugation and plated on coverslips. Within 24-48 hr, neurite outgrowth occurs and neurons can be identified by pan-neuronal markers. After two days in culture, isolated neurons fire action potentials as observed by patch clamp studies. Furthermore, enteric glia can also be identified by GFAP staining. A network of neurons and glia in close apposition forms within 5 - 7 days. Enteric neurons can be individually and directly studied using methods such as immunohistochemistry, electrophysiology, calcium imaging, and single-cell PCR. Furthermore, this procedure can be performed in genetically modified animals. This methodology is simple to perform and inexpensive. Overall, this protocol exposes the components of the enteric nervous system in an easily manipulated manner so that we may better discover the functionality of the ENS in normal and disease states.

An In-vitro Preparation of Isolated Enteric Neurons and Glia from the Myenteric Plexus of the Adult Mouse

We demonstrate a cell culture protocol for the direct study of neuronal and glial components of the enteric nervous system. A neuron/glia mixed culture on coverslips is prepared from the myenteric plexus of adult mouse providing the ability to examine individual neuron and glia function by electrophysiology, immunohistochemical, etc.

Un<em&gt; In-vitro</em&gt; Preparazione dei neuroni enterici isolati e glia dal plesso mienterico del topo adulto

The enteric nervous system is a vast network of neurons and glia running the length of the gastrointestinal tract that functionally controls ...

Retrograde Labeling of Retinal Ganglion Cells in Adult Zebrafish with Fluorescent Dyes

As retrograde labeling retinal ganglion cells (RGCs) can isolate RGCs somata from dying sites, it has become the gold standard for counting RGCs in RGCs survival and regeneration experiments. Many studies have been performed in mammalian animals to research RGCs survival after optic nerve injury. However, retrograde labeling of RGCs in adult zebrafish has not yet been reported, though some alternative methods can count cell numbers in retinal ganglion cell layers (RGCL). Considering the small size of the adult zebrafish skull and the high risk of death after drilling on the skull, we open the skull with the help of acid-etching and seal the hole with a light curing bond, which could significantly improve the survival rate. After absorbing the dyes for 5 days, almost all the RGCs are labeled. As this method does not need to transect the optic nerve, it is irreplaceable in the research of RGCs survival after optic nerve crush in adult zebrafish. Here, we introduce this method step by step and provide representative results.

We introduce an efficient method to retrograde label retinal ganglion cells (RGCs) in adult zebrafish.

Etichettatura retrograda di cellule gangliari della retina in Zebrafish adulti con coloranti fluorescenti

As retrograde labeling retinal ganglion cells (RGCs) can isolate RGCs somata from dying sites, it has become the gold standard for counting RGCs in RGCs ...

The Olfactory System as a Model to Study Axonal Growth Patterns and Morphology In Vivo

The olfactory system has the unusual capacity to generate new neurons throughout the lifetime of an organism. Olfactory stem cells in the basal portion of the olfactory epithelium continuously give rise to new sensory neurons that extend their axons into the olfactory bulb, where they face the challenge to integrate into existing circuitry. Because of this particular feature, the olfactory system represents a unique opportunity to monitor axonal wiring and guidance, and to investigate synapse formation. Here we describe a procedure for in vivo labeling of sensory neurons and subsequent visualization of axons in the olfactory system of larvae of the amphibian Xenopus laevis. To stain sensory neurons in the olfactory organ we adopt the electroporation technique. In vivo electroporation is an established technique for delivering fluorophore-coupled dextrans or other macromolecules into living cells. Stained sensory neurons and their axonal processes can then be monitored in the living animal either using confocal laser-scanning or multiphoton microscopy. By reducing the number of labeled cells to few or single cells per animal, single axons can be tracked into the olfactory bulb and their morphological changes can be monitored over weeks by conducting series of in vivo time lapse imaging experiments. While the described protocol exemplifies the labeling and monitoring of olfactory sensory neurons, it can also be adopted to other cell types within the olfactory and other systems.

The Olfactory System as a Model to Study Axonal Growth Patterns and Morphology In Vivo

We describe a protocol for in vivo labeling of olfactory sensory neurons by electroporation and subsequent confocal laser-scanning or multiphoton microscopy to visualize neuronal morphology and its development over time.

Il sistema olfattivo come modello per studiare gli schemi di crescita assonale e Morfologia<em&gt; In Vivo</em

The olfactory system has the unusual capacity to generate new neurons throughout the lifetime of an organism. Olfactory stem cells in the basal portion of ...

The Indirect Neuron-astrocyte Coculture Assay: An In Vitro Set-up for the Detailed Investigation of Neuron-glia Interactions

Proper neuronal development and function is the prerequisite of the developing and the adult brain. However, the mechanisms underlying the highly controlled formation and maintenance of complex neuronal networks are not completely understood thus far. The open questions concerning neurons in health and disease are diverse and reaching from understanding the basic development to investigating human related pathologies, e.g.,&#160;Alzheimer&#39;s disease and&#160;Schizophrenia. The most detailed analysis of neurons can be performed in vitro. However, neurons are demanding cells and need the additional support of astrocytes for their long-term survival. This cellular heterogeneity is in conflict with the aim to dissect the analysis of neurons and astrocytes. We present here a cell-culture assay that allows for the long-term cocultivation of pure primary neurons and astrocytes, which share the same chemically defined medium, while being physically separated. In this setup, the cultures survive for up to four weeks and the assay is suitable for a diversity of investigations concerning neuron-glia interaction.

The Indirect Neuron-astrocyte Coculture Assay: An In Vitro Set-up for the Detailed Investigation of Neuron-glia Interactions

This protocol describes the indirect neuron-astrocyte coculture for compartmentalized analysis of neuron-glia interactions.

La indiretto Neuron-astrociti co-coltura saggio: An<em&gt; In Vitro</em&gt; Set-up per l&#39;indagine dettagliata delle Interazioni neuroni-glia

Proper neuronal development and function is the prerequisite of the developing and the adult brain. However, the mechanisms underlying the highly ...

M&#252;ller Glia Cell Activation in a Laser-induced Retinal Degeneration and Regeneration Model in Zebrafish

A fascinating difference between teleost and mammals is the lifelong potential of the teleost retina for retinal neurogenesis and regeneration after severe damage. Investigating the regeneration pathways in zebrafish might bring new insights to develop innovative strategies for the treatment of retinal degenerative diseases in mammals. Herein, we focused on the induction of a focal lesion to the outer retina in adult zebrafish by means of a 532 nm diode laser. A localized injury allows investigating biological processes that take place during retinal degeneration and regeneration directly at the area of damage. Using non-invasive optical coherence tomography (OCT), we were able to define the location of the damaged area and monitor subsequent regeneration in vivo. Indeed, OCT imaging produces high-resolution, cross-sectional images of the zebrafish retina, providing information which was previously only available with histological analyses. In order to confirm the data from real-time OCT, histological sections were performed and regenerative response after the induction of the retinal injury was investigated by immunohistochemistry.

M&amp;#252;ller Glia Cell Activation in a Laser-induced Retinal Degeneration and Regeneration Model in Zebrafish

The zebrafish is a popular animal model to study mechanisms of retinal degeneration/regeneration in vertebrates. This protocol describes a method to induce localized injury disrupting the outer retina with minimal damage to the inner retina. Subsequently, we monitor in vivo the retinal morphology and the M&#252;ller glia response throughout retinal regeneration.

Attivazione delle cellule di Glia di Müller in una degenerazione retinica indotta da Laser e un modello di rigenerazione in Zebrafish

A fascinating difference between teleost and mammals is the lifelong potential of the teleost retina for retinal neurogenesis and regeneration after ...

Investigating Mammalian Axon Regeneration: In Vivo Electroporation of Adult Mouse Dorsal Root Ganglion

Electroporation is an essential non-viral gene transfection approach to introduce DNA plasmids or small RNA molecules into cells. A sensory neuron in the dorsal root ganglion (DRGs) extends a single axon with two branches. One branch goes to the peripheral nerve (peripheral branch), and the other branch enters the spinal cord through the dorsal root (central branch). After the neural injury, the peripheral branch regenerates robustly whereas the central branch does not regenerate. Due to the high regenerative capacity, sensory axon regeneration has been widely used as a model system to study mammalian axon regeneration in both the peripheral nervous system (PNS) and the central nervous system (CNS). Here, we describe a previously established approach protocol to manipulate gene expression in mature sensory neurons in vivo via electroporation. Based on transfection with plasmids or small RNA oligos (siRNAs or microRNAs), the approach allows for both loss- and gain-of-function experiments to study the roles of genes-of-interests or microRNAs in regulation of axon regeneration in vivo. In addition, the manipulation of gene expression in vivo can be controlled both spatially and temporally within a relatively short time course. This model system provides a unique tool to investigate the molecular mechanisms by which mammalian axon regeneration is regulated in vivo.

Investigating Mammalian Axon Regeneration: In Vivo Electroporation of Adult Mouse Dorsal Root Ganglion

Electroporation is an effective approach to deliver genes of interests into cells. By applying this approach in vivo on the neurons of adult mouse dorsal root ganglion (DRG), we describe a model to study axon regeneration in vivo.

Inquirenti rigenerazione dell'assone dei mammiferi: In Vivo elettroporazione del ganglio di radice dorsale del topo adulto

Electroporation is an essential non-viral gene transfection approach to introduce DNA plasmids or small RNA molecules into cells. A sensory neuron in the ...