Este trabalho foi apoiado financeiramente pelo projeto SAF2017-82736-C2-1-R do Ministerio de Ciencia e Innovación para o MTM-F e pela Fundación Universidad Francisco de Vitória ao JS.

NOTA: A experimentação animal foi aprovada pelos comitês nacionais e institucionais de bioética.
1. ihOEG (Ts12 e Ts14) cultura
NOTA: Este procedimento é feito em condições estéreis em um armário de biossegurança da cultura tecidual.
<ol><li>Prepare o meio de cultura OEG ME10 de 50 mL conforme previsto na Tabela 1.</li>
	<li>Prepare 5 mL de DMEM/F12-FBS, conforme fornecido na Tabela 1, em tubo cônico de 15 mL.</li>
	<li>Aqueça ambas as mídias a 37 °C em um banho de água limpa, por 15 minutos.</li>
	<li>Descongele os frascos de células Ts12 e Ts14 a 37 °C em um banho de água limpa.</li>
	<li>Resuspend e adicione células ao meio de cultura DMEM/F12-FBS preparado na etapa 2.</li>
	<li>Centrífuga por 5 min a 200 x g.</li>
	<li>Aspire o supernatante.</li>
	<li>Adicione 500 μL de me10 médio e resuspense a pelota.</li>
	<li>Prepare um prato de cultura celular p60 com 3 mL de ME10 e adicione a suspensão celular, dropwise.</li>
	<li>Mova-se para distribuir as células uniformemente através da placa.</li>
	<li>Células de cultura a 37 °C em 5% DE CO2. NOTA: Depois de atingir a confluência, pelo menos outra passagem deve ser feita para otimizar as células para a cocultura. 90% de confluência é necessária antes de semeá-las nas tampas para cocultura. Um p-60 confluente tem um número celular médio de 7 x 105 para Ts14 e 2,5 x 106 para linhas celulares Ts12. As linhas de celular Ts12 e Ts14 devem ser passagem a cada 2-3 dias.</li>
</ol>2. Preparação do ihOEG (Ts12 e Ts14) para o ensaio
NOTA: Esta etapa deve ser feita 24 horas antes da dissecção e cocultura da RGN.
<ol><li>Trate as tampas de 12 mm Ø com 10 μg/mL de poli-l-lisina (PLL) por 1 h. NOTA: Os deslizamentos podem ser deixados durante a noite na solução PLL.</li>
	<li>Lave as tampas com 1x de soro fisiológico tampão de fosfato (PBS), três vezes.</li>
	<li>Despete células Ts12 e Ts14 ihOEG do prato de cultura celular p60.<ol>
<li>Adicione 4 mL de meio de cultura DMEM/F12-FBS(Tabela 1) a um tubo cônico de 15 mL. Aqueça a 37 °C em um banho de água limpa.</li>
		<li>Remova o meio das placas e lave as células com 1 mL de 1x PBS-EDTA, uma vez.</li>
		<li>Adicione 1 mL de trypsin-EDTA às células OEG e incubar por 3-5 min a 37 °C, 5% CO2.
</li>
		<li>Colete células com uma pipeta p1000 e transfira-as para o meio preparado na etapa 3.1.</li>
		<li>Centrífuga por 5 min a 200 x g.</li>
		<li>Aspire o supernatante.</li>
		<li>Adicione 1 mL de média ME10 e resuspense a pelota.</li>
		<li>Conte o número da célula em um hemócito.</li>
	</ol>
</li>
	<li>Semente 80.000 células Ts14 ou 100.000 células Ts12/bem nas tampas em placas de 24 poços em 500 μL de me10 médio.</li>
	<li>Células de cultura a 37 °C em 5% de CO2, por 24 h.</li>
</ol>3. Dissecção do tecido retiniano
NOTA: Ratos Wistar machos de 2 meses de idade são usados como fonte RGN. Duas retinas (um rato) para 20 poços de um prato de célula de 24 poços. Material cirúrgico autoclave antes do uso. O kit de dissociação papain é comprado comercialmente(Tabela de Materiais). Siga as instruções do provedor para a reconstituição. Reconstituir D,L-2-amino-5-ácido fosfosfosfonovalerico (APV) em estoque de 5 mM e preparar as alíquotas.
<ol><li>No dia do ensaio, prepare a seguinte mídia.<ol>
<li>Prepare um prato de cultura celular p60 com 5 mL de EBSS frio (frasco 1 do kit de dissociação papain).</li>
		<li>Prepare um prato de cultura celular p60 com frasco reconstituído 2 (papain) do kit de dissociação papain mais 50 μL de APV.  Em seguida, adicione 250 μL de frasco desprointitulado 3 (DNase mais 5 μL de APV).</li>
		<li>Em uma mistura de tubo estéril de 2,7 mL de frasco 1 com 300 μL de frasco 4 (inibidor de protease albumina-ovomucoid). Adicione 150 μL de frasco 3 (DNase) mais 30 μL de APV.</li>
		<li>Prepare 20 mL de neurobasal-B27 médio (NB-B27) conforme previsto na Tabela 1.</li>
	</ol>
</li>
	<li>Sacrifique um rato por asfixia com CO2.</li>
	<li>Remova a cabeça por decapitação com guilhotina; colocá-lo em uma placa de Petri de 100 mm e pulverizar a cabeça com etanol 70% antes de colocá-lo em um capô de fluxo laminar.</li>
	<li>Corte os bigodes do rato com uma tesoura para que não interfiram com a manipulação dos olhos.</li>
	<li>Segure o nervo óptico com fórceps para puxar o globo ocular o suficiente para ser capaz de fazer uma incisão através do olho com um bisturi.</li>
	<li>Remova a lente e o humor vítreo e puxe a retina (tecido laranja), enquanto as camadas restantes do olho ficam dentro (incluindo a camada epitelial do pigmento).</li>
	<li>Coloque a retina no prato de cultura celular p60 preparado na etapa 3.1.1.</li>
	<li>Transfira a retina para o prato de cultura celular p60 preparado na etapa 3.1.2 e corte-a com o bisturi em pequenos pedaços de tamanho aproximado < 1 mm.</li>
	<li>Transfira para um tubo de plástico de 15 mL.</li>
	<li>Incubar o tecido por 30 minutos, em uma incubadora umidificada a 37 °C abaixo de 5% de CO2,com agitação a cada 10 minutos.</li>
	<li>Dissociar aglomerados de células por pipetting para cima e para baixo com uma pipeta Pasteur de vidro.</li>
	<li>Centrifugar a suspensão celular a 200 x g por 5 min.</li>
	<li>Descarte o supernaente e inativar o papain, resuspenque a pelota celular na solução preparada na etapa 3.1.3. (1,5 mL para 2 olhos).</li>
	<li>Encolé-lo cuidadosamente em 5 mL de frasco reconstituído 4.</li>
	<li>Centrifugar a 200 x g por 5 min.</li>
	<li>Enquanto centrifuga, remova completamente o meio ME-10 da placa de célula de poço OEG 24 (previamente preparado na etapa 2) e substitua-o por 500 μL de meio NB-B27 por poço.</li>
	<li>Descarte o supernasce e resuspenque as células em 2 mL de meio NB-B27.</li>
	<li>Placa 100 μL de suspensão celular de retina, por poço da placa m24, em deslizamentos de monocamadas tratados com PLL ou OEG.</li>
	<li>Mantenha as culturas a 37 °C com 5% de CO2 para 96 h no meio NB-B27.</li>
</ol>4. Imunostaining
<ol><li>Após 96 h, fixar as células por 10 min adicionando o mesmo volume de 4% de paraformaldeído (PFA) em 1x PBS ao meio de cultura (600 μL) (concentração final pfa 2%).</li>
	<li>Remova a mídia e o PFA da placa de 24-multiwell e adicione mais uma vez 500 μL de 4% de paraformaldeído (PFA) em 1x PBS. Incubar por 10 minutos.</li>
	<li>Descarte o fixador e lave 3 vezes com 1x PBS por 5 minutos.</li>
	<li>Bloco com 0,1% Triton X-100/1% FBS em PBS (PBS-TS) por 30-40 min.</li>
	<li>Prepare os anticorpos primários no tampão PBS-TS da seguinte forma: Anticorpo monoclonal SMI31 (contra proteínas MAP1B e NF-H) (1:500). 514 (reconhece proteínas MAP2A e B) antiserum policlonal de coelho (1:400).</li>
	<li>Adicione anticorpos primários às coculturas e incubar durante a noite a 4 °C.</li>
	<li>No dia seguinte, descarte os anticorpos e lave as tampas com 1x PBS, 3 vezes, por 5 minutos.</li>
	<li>Prepare os anticorpos secundários no buffer PBS-TS da seguinte forma: Para SMI-31, anti-mouse Alexa Fluor 488 (1:500). Para 514, anti-coelho Alexa-594 (1:500).</li>
	<li>Incubar células com os anticorpos secundários fluorescentes correspondentes por 1h, em RT, no escuro.</li>
	<li>Lave as tampas com 1x PBS, 3 vezes, por 5 min, no escuro.</li>
	<li>Por fim, monte as tampas com meio de montagem(Tabela de Materiais) e mantenha a 4 °C. NOTA: Sempre que necessário, pode ser realizada a coloração de núcleos fluorescentes com DAPI (4,6-diamidino-2-fenilôndole). Antes de montar, incubar as células por 10 minutos no escuro com DAPI (10 μg/mL em 1x PBS). Lave as tampas 3 vezes com 1x PBS e, finalmente, monte as tampas com o meio de montagem.</li>
</ol>5. Quantificação da regeneração axonal
NOTA: As amostras são quantificadas sob o objetivo de 40x de um microscópio de epifluorescência. Um mínimo de 30 fotos devem ser tiradas em campos aleatórios, com pelo menos 200 neurônios, a serem quantificadas para cada tratamento. Cada experimento deve ser repetido um mínimo de três vezes.
<ol><li>Quantifique a porcentagem de neurônios com axônio (neurite positivo SMI31) em relação à população total de RGNs (identificada com map2A/B 514 imunostaining positivo do corpo neuronal e dendritos).</li>
	<li>Quantifique o índice de regeneração axonal ou o comprimento axonal médio (μm/neurônio). Este parâmetro é definido como a soma dos comprimentos (em μm) de todos os axônios identificados, divididos pelo número total de neurônios contados, apresentando um axônio ou não. O comprimento axonal é determinado usando o neuronj plugin do software de imagem ImageJ (NIH-USA).</li>
	<li>Calcule a média, o desvio padrão e a significância estatística usando o software apropriado.</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>

Os autores não têm nada a revelar.

O transplante de OEG em locais de lesão do CNS é considerado uma terapia promissora para lesão do CNS devido às suas propriedades pró-neuroregenerativas constitutivas7,8,9. No entanto, dependendo da fonte de tecido — mucosa olfativa (OM-OEG) versus lâmpada olfativa (OB-OEG)— ou a idade do doador, existe uma variação considerável nessa capacidade26,31,</...

Os neurônios do sistema nervoso central adulto (SNC) têm capacidade regenerativa limitada após lesão ou doença. Uma estratégia comum para promover a regeneração do SNC é o transplante, no local da lesão, de tipos celulares que induzem o crescimento axonal, como células-tronco, células schwann, astrócitos ou células ensheathing glia (OEG)1,2,3,4,5.
OEG deriva da crista neural6 e se localiza na mucosa olfativa e na lâmpada olfativa. No adulto, neurônios sensoriais olfativos morrem regularmente como resultado da exposição ambiental e são substituídos por neurônios recém-diferenciados. O OEG circunda e guia esses novos axônios olfativos para entrar na lâmpada olfativa e estabelecer novas sinapses com seus alvos no CNS7. Devido a esses atributos fisiológicos, o OEG tem sido utilizado em modelos de lesão de SNC, como lesão medular ou nervo óptico e suas propriedades neurorregenerativas e neuroprotetoras se tornamcomprovadas 8,9,10,11. Vários fatores foram identificados como responsáveis pelas características pró-regenerativas dessas células, incluindo a produção ou secreção de proteases de matriz extracelular ou secreção dos fatores de crescimento neurotrófico e axonal12,13,14.
Dadas as limitações técnicas para expandir as células primárias de OEG, estabelecemos e caracterizamos linhas clonais de OEG humano igênitas reversíveis (ihOEG), que fornecem um fornecimento ilimitado de OEG homogêneo. Estas células ihOEG derivam de culturas primárias, preparadas a partir de lâmpadas olfativas obtidas em autópsias. Eles foram imortalizados pela transdução da subunidade catalítica telomerase (TERT) e do oncogene Bmi-1 e modificados com o vírus SV40 grande antígeno T15,16,17,18. Duas dessas linhas celulares ihOEG são Ts14, que mantém a capacidade regenerativa das culturas originais e Ts12, uma linha regenerativa baixa que é usada como baixo controle de regeneração nesses experimentos18.
Para avaliar a capacidade de OEG para promover a regeneração axonal após lesão neural, vários modelos in vitro foram implementados. Nesses modelos, o OEG é aplicado a culturas de diferentes origens neuronais e formação de neurita e alongamento — em resposta à cocultura gliana — são avaliados. Exemplos dessas fontes neuronais são neurônios corticais neonatais de ratos19, feridas de arranhão realizadas em neurônios embrionários de ratos de tecido cortical20, explanações de retina de rato21,neurônios hipotalâmicos ou hipocampais22,23, neurônios gânglios de raiz dorsal de rato pós-natal24, neurônios do trato corticospinal do camundongo pós-natal25, neurônios NT2 humanos26, ou neurônios corticais cerebrais pós-natal em culturas de cicatriz de astrócito reativas27.
Nesses modelos, no entanto, o ensaio de regeneração conta com neurônios embrionários ou pós-natais, que têm uma plasticidade intrínseca que está ausente em neurônios adultos feridos. Para superar essa desvantagem, apresentamos um modelo de regeneração axonal adulta em coculturas de linhas de OEG com neurônios gânglios de retina adulta (RGNs), baseado no originalmente desenvolvido por Wigley et al.28,29,30,31 e modificados e usados pelo nosso grupo12,13,14,15,16,17,18,32,33. Resumidamente, o tecido retiniano é extraído de ratos adultos e digerido com papain. A suspensão das células de retina é então banhada em deslizamentos tratados com polilise ou em monocamadas Ts14 e Ts12. As culturas são mantidas por 96 h antes de serem fixadas e, em seguida, a imunofluorescência para proteínas axona (MAP1B e NF-H)34 e somatodendritic (MAP2A e B)35 marcadores são realizados. A regeneração axonal é quantificada como uma porcentagem de neurônios com axônio, em relação à população total de RGNs e o índice de regeneração axonal é calculado como o comprimento axonal médio por neurônio. Este protocolo não é apenas útil para avaliar o potencial neuroregenerativo do IhOEG, mas pode ser estendido a diferentes fontes de OEG ou outras células gliais.

<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

As células de glia ensheathing olfativas (OEG) são localizadas desde a mucosa olfativa até e para a camada nervosa olfativa (ONL) da lâmpada olfativa. Ao longo da vida adulta, eles são fundamentais para o crescimento axonal de neurônios olfativos recém-gerados, da lamina propria ao ONL. Devido às suas propriedades pró-regenerativas, essas células têm sido usadas para promover a regeneração axonal em modelos de lesão medular ou nervo óptico.
Apresentamos um modelo in vitro para avaliar e medir a capacidade neurorregenerativa do OEG após lesão neural. Neste modelo, o OEG humano reversivelmente imortalizado (ihOEG) é cultivado como uma monocamada, as retinas são extraídas de ratos adultos e neurônios de gânglios retinais (RGN) são coculturados na monocamada OEG. Após 96 h, marcadores axonais e somatodendritic em RGNs são analisados por imunofluorescência e o número de RGNs com axônio e o comprimento/neurônio axonal médio são quantificados.
Este protocolo tem a vantagem sobre outros ensaios in vitro que dependem de neurônios embrionários ou pós-natais, que avaliam propriedades neuroregenerativas OEG no tecido adulto. Além disso, não é apenas útil para avaliar o potencial neuroregenera do ihOEG, mas pode ser estendido para diferentes fontes de OEG ou outras células gliais.

Neste protocolo, apresentamos um modelo in vitro para avaliar a capacidade neuroregenerativa de OEG após lesão neuronal. Como mostrado na Figura 1, a fonte OEG é uma linha de células clonal oeg humana imortalizada reversível -Ts14 e Ts12-, que deriva de culturas primárias, preparadas a partir de lâmpadas olfativas obtidas nas autópsias15,17,18. O tecido retiniano é extraído de ratos adulto...

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

Apresentamos um modelo in vitro para avaliar a capacidade neurorregenerativa de glia ensheathing glia (OEG), após lesão neural. Baseia-se em uma cocultura de neurônios gânglios de retina adulto axotomizados (RGN) em monocamadas OEG e estudo subsequente de regeneração axonal, analisando marcadores axonal e somatodendritic RGN.

Cocultura de Neurônios de Gânglio Axotomizado de Rato Retinal com Glia Ensheathing Olfactory, como um Modelo In Vitro de Regeneração Axonal 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 visualizações.  Universidad Francisco de Vitoria. Apresentamos um modelo in vitro para avaliar a capacidade neurorregenerativa de glia ensheathing glia (OEG), após lesão neural. Baseia-se em uma cocultura de neurônios gânglios de retina adulto axotomizados (RGN) em monocamadas OEG e estudo subsequente de regeneração axonal, analisando marcadores axonal e somatodendritic RGN.

Vídeo: 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-cultura de neurônios de rato Primária Cortical 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 ...

Neurociência

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.

Transdução Viral seletiva de Adultos-nascido neurônios olfativos de crônica In vivo Estímulo Optogenetic

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.

Estudo genético da regeneração do axônio com cultivadas Adulto neurônios do gânglio da raiz dorsal

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.

Transplante de células olfativas Ensheathing para avaliar a recuperação funcional após a lesão do nervo periférico

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.

Um<em&gt; In-vitro</em&gt; Preparação de neurônios entéricos isolados e células gliais do plexo mioentérico do Rato 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.

Marcação retrógrada de células ganglionares da retina em Zebrafish Adulto com corantes fluorescentes

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.

O Sistema Olfativo como um modelo para estudar os padrões de crescimento axonal 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.

A indireta Neuron-astrócitos Coculture Ensaio: An<em&gt; In Vitro</em&gt; Set-up para a investigação detalhada da Relação Neuron-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.

Ativação de células da Müller Glia em um modelo de regeneração no Zebrafish e degeneração retiniana induzida por Laser

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.

Investigação regeneração do axônio mamíferos: In Vivo Electroporation do gânglio de raiz Dorsal do rato 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 ...