Name: Autor em destaque: Otimizando o desenvolvimento neurovascular do organoide do cérebro humano em embrião de galinha
Uploaded: 2024-02-16T13:00:00
Description: Watch this Scientific Journal Video about Author Spotlight: Optimizing the Neurovascular Development of Human Brain Organoid in Chick Embryo at JoVE.com

Agradecemos ao Dr. Alcántara e ao Dr. Ortega do UB e ao resto dos membros do laboratório do Dr. Acosta pelas discussões perspicazes. S.A. é professor assistente da Generalitat de Catalunya da Universitat de Barcelona.

Os embriões de galinha-de-leghorn (Gallus gallus) foram tratados seguindo o Guide for the Care and Use of Laboratory Animals do Institute of Laboratory Animals Resources, Commission of Life Sciences, National Research Council, EUA, e os experimentos foram aprovados pelo Council for Care and Use of Experimental Animals da Universidade de Barcelona.
1. Preparação organoide cerebral não guiada
<ol><li>Manter as células estaminais embrionárias humanas H9 (hESCs) e...

Enxertia de organoides cerebrais humanos na membrana corioalantóide do embrião de pintinho

<ol>
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Y., 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=Generation+of+vascularized+brain+organoids+to+study+neurovascular+interactions.">Generation of vascularized brain organoids to study neurovascular interactions.</a> Elife. 11, e76707 (2022).</li><li>Paredes, I., 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=Oligodendrocyte+precursor+cell+specification+is+regulated+by+bidirectional+neural+progenitor-endothelial+cell+crosstalk.">Oligodendrocyte precursor cell specification is regulated by bidirectional neural progenitor-endothelial cell crosstalk.</a> Nat Neurosci. 24 (4), 478-488 (2021).</li><li>Matsui, T. K., Tsuru, Y., Hasegawa, K., Kuwako, K. 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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=Generation+of+human+vascularized+brain+organoids.">Generation of human vascularized brain organoids.</a> Neuroreport. 29 (7), 588-593 (2018).</li><li>Cakir, B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Engineering+of+human+brain+organoids+with+a+functional+vascular-like+system.">Engineering of human brain organoids with a functional vascular-like system.</a> Nat Methods. 16 (11), 1169-1175 (2019).</li><li>Shi, Y., 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=Vascularized+human+cortical+organoids+(vorganoids)+model+cortical+development+in+vivo.">Vascularized human cortical organoids (vorganoids) model cortical development in vivo.</a> PLoS Biol. 18 (5), e3000705 (2020).</li><li>Mansour, A. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+in+vivo+model+of+functional+and+vascularized+human+brain+organoids.">An in vivo model of functional and vascularized human brain organoids.</a> Nat Biotechnol. 36 (5), 432-441 (2018).</li><li>Revah, O., 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=Maturation+and+circuit+integration+of+transplanted+human+cortical+organoids.">Maturation and circuit integration of transplanted human cortical organoids.</a> Nature. 610 (7931), 319-326 (2022).</li><li>Ribatti, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chicken+chorioallantoic+membrane+angiogenesis+model.">Chicken chorioallantoic membrane angiogenesis model.</a> Methods Mol Biol. 843, 47-57 (2012).</li><li>Nowak-Sliwinska, P., Segura, T., Iruela-Arispe, M. 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A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microvascular+experimentation+in+the+chick+chorioallantoic+membrane+as+a+model+for+screening+angiogenic+agents+including+from+gene-modified+cells.">Microvascular experimentation in the chick chorioallantoic membrane as a model for screening angiogenic agents including from gene-modified cells.</a> Int J Mol Sci. 23 (1), 452 (2021).</li><li>Garreta, 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=Fine+tuning+the+extracellular+environment+accelerates+the+derivation+of+kidney+organoids+from+human+pluripotent+stem+cells.">Fine tuning the extracellular environment accelerates the derivation of kidney organoids from human pluripotent stem cells.</a> Nat Mater. 18 (4), 397-405 (2019).</li><li>Kaisto, 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=Optimization+of+renal+organoid+and+organotypic+culture+for+vascularization,+extended+development,+and+improved+microscopy+imaging.">Optimization of renal organoid and organotypic culture for vascularization, extended development, and improved microscopy imaging.</a> J Vis Exp. (157), e60995 (2020).</li><li>Varzideh, 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=Human+cardiomyocytes+undergo+enhanced+maturation+in+embryonic+stem+cell-derived+organoid+transplants.">Human cardiomyocytes undergo enhanced maturation in embryonic stem cell-derived organoid transplants.</a> Biomaterials. 192, 537-550 (2019).</li><li>Komatsu, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+cam+model+for+cic-dux4+sarcoma+and+its+potential+use+for+precision+medicine.">The cam model for cic-dux4 sarcoma and its potential use for precision medicine.</a> Cells. 10 (10), 2613 (2021).</li><li>Worsdorfer, 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=Generation+of+complex+human+organoid+models+including+vascular+networks+by+incorporation+of+mesodermal+progenitor+cells.">Generation of complex human organoid models including vascular networks by incorporation of mesodermal progenitor cells.</a> Sci Rep. 9 (1), 15663 (2019).</li><li>Janzer, R. C., Jaff, M. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Astrocytes+induce+blood-brain+barrier+properties+in+endothelial+cells.">Astrocytes induce blood-brain barrier properties in endothelial cells.</a> Nature. 325 (6101), 253-257 (1987).</li><li>Janzer, R. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+blood-brain+barrier:+Cellular+basis.">The blood-brain barrier: Cellular basis.</a> J Inherit Metab Dis. 16 (4), 639-647 (1993).</li><li>Lobrinus, J. A., Juillerat-Jeanneret, L., Darekar, P., Schlosshauer, B., Janzer, R. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Induction+of+the+blood-brain+barrier+specific+ht7+and+neurothelin+epitopes+in+endothelial+cells+of+the+chick+chorioallantoic+vessels+by+a+soluble+factor+derived+from+astrocytes.">Induction of the blood-brain barrier specific ht7 and neurothelin epitopes in endothelial cells of the chick chorioallantoic vessels by a soluble factor derived from astrocytes.</a> Brain Res Dev Brain Res. 70 (2), 207-211 (1992).</li><li>Holash, J. A., Stewart, P. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chorioallantoic+membrane+(cam)+vessels+do+not+respond+to+blood-brain+barrier+(bbb)+induction.">Chorioallantoic membrane (cam) vessels do not respond to blood-brain barrier (bbb) induction.</a> Adv Exp Med Biol. 331, 223-228 (1993).</li><li>Holash, J. A., Noden, D. 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Neste estudo, descrevemos um protocolo detalhado com inúmeras etapas fundamentais que proporcionam crescimento e desenvolvimento favoráveis de organoides cerebrais humanos após a enxertia sem perturbar a sobrevivência dos embriões de galinha. Recomendamos o uso de agulhas estéreis para puncionar a câmara de ar do ovo após 24 h de incubação (dia 1). Além disso, também tentamos fazer a punção no 4º dia (após verificar a casca do ovo com luz para testar o desenvolvimento da vasculatura para ter certeza de qu...

Os organoides cerebrais humanos são uma técnica emergente que nos permite recapitular in vitro o desenvolvimento inicial do cérebro humano 1,2,3. No entanto, uma das principais limitações desse modelo é a falta de vascularização, que desempenha papéis indispensáveis não só na homeostase cerebral, mas também no desenvolvimentocerebral4. Além da oferta de oxigênio e nutrientes, evidências acumuladas sugerem que o sistema vascular cerebral regula a diferenciação neural, migração e sinaptogênese durante o desenvolvimento 5,6. Portanto, há uma necessidade urgente de estabelecer modelos confiáveis que possam fornecer a sinalização e a estrutura vascular ausente aos organoides cerebrais, aumentando a complexidade da geração de organoides cerebrais humanos7.
Dentre os métodos de vascularização propostos, duas principais linhas de atuação podem ser consideradas: enxertia organoide em organismo vivo e tecnologias puramente in vitro co-cultivando células endoteliais e neurais8,9,10,11,12. O transplante intracerebral em camundongos é caro e demorado, tornando outras tecnologias relevantes para modelos mais simples. O ensaio de membrana corioalantóide (CAM) em pintinhos tem sido amplamente utilizado para estudar a angiogênese 13,14,15. Na última década, vários grupos enxertaram com sucesso diferentes tipos de organoides, incluindo organoidesrenais16,17, cardíacos18 e tumorais19,20, em CAMs. No entanto, pouco se sabe sobre a eficácia, toxicidade/rejeição, efeito fisiológico e métodos para enxertar organoides cerebrais humanos no CAM. Outro aspecto interessante e ainda inexplorado é a formação de uma barreira hematoencefálica quimérica (BHE) entre as MAC e a interface astrocitária organoide. Trabalhos pioneiros anteriores sugeriram a viabilidade putativa de gerar uma BBB na CAM por meio do transplante de astrócitos e meio condicionado por astrócitos 21,22,23. No entanto, astrócitos maduros parecem ser incapazes de atingir esseobjetivo 24,25. Assim, a formação induzida por astrócitos do BBB permanece discutível, e o transplante de organoides cerebrais humanos nos permitiria lançar luz sobre essa controvérsia.
Este artigo em vídeo descreve um protocolo para um transplante in ovo de organoides cerebrais humanos em CAM que promove crescimento, melhora e vascularização, resultando em organoides que englobam elementos BBB histologicamente compatíveis. Aqui, apresentamos um protocolo garantindo a sobrevivência do embrião de galinha e relatamos a permissividade da CAM para sustentar o crescimento organoide cerebral.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Anti-TUBB3 [Tuj1], mouse&#160;</td>
			<td>BioLegend</td>
			<td>801201</td>
			<td>1:1,000</td>
		</tr>
		<tr>
			<td>Anti-GFAP, rabbit</td>
			<td>GeneTex</td>
			<td>GTX108711</td>
			<td>1:500</td>
		</tr>
		<tr>
			<td>Anti-rabbit AlexaFluor 488, goat.</td>
			<td>Invitrogen</td>
			<td>A-21206</td>
			<td>1:1,000</td>
		</tr>
		<tr>
			<td>Anti-mouse AlexaFluor 594, goat</td>
			<td>Jackson ImmunoResearch</td>
			<td>715-585-150</td>
			<td>1:500</td>
		</tr>
		<tr>
			<td>Fertilized White Leghorn chicken (Gallus gallus) eggs</td>
			<td>Granja Gibert (Cambrils, Spain)</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>DAPI</td>
			<td>Invitrogen</td>
			<td>D1306</td>
			<td>1:10,000</td>
		</tr>
		<tr>
			<td>DPX</td>
			<td>Sigma</td>
			<td>100579</td>
			<td>xylene-based mounting medium&#160;</td>
		</tr>
		<tr>
			<td>Gentle Dissociation Solution</td>
			<td>CreativeBiolabs</td>
			<td>ITS-0622-YT187</td>
			<td>cell dissociation solution</td>
		</tr>
		<tr>
			<td>Matrigel</td>
			<td>BD Biosciences</td>
			<td>356234</td>
			<td></td>
		</tr>
		<tr>
			<td>Mowiol 4-88 mounting media</td>
			<td>Merk</td>
			<td>81381</td>
			<td></td>
		</tr>
		<tr>
			<td>Paper towel, lab-grade</td>
			<td>Sigma-Aldrich</td>
			<td>Z188956</td>
			<td></td>
		</tr>
		<tr>
			<td>ROCK inhibitor Y27632</td>
			<td>Millipore</td>
			<td>SCM075</td>
			<td>10 nM</td>
		</tr>
		<tr>
			<td>Sharp-Point Surgical Scissors</td>
			<td>VWR</td>
			<td>470106-340</td>
			<td></td>
		</tr>
		<tr>
			<td>Superfrost Plus Adhesion Microscope Slides</td>
			<td>Epredia</td>
			<td>J1800AMNZ</td>
			<td></td>
		</tr>
	</tbody>
</table>

early unguided human brain organoid neurovascular niche modeling into the permissive chick embryo chorioallantoic membrane

A enxertia de organoides em tecidos vascularizados em animais modelo, como a membrana corioalantóide (CAM) imunodeficiente de camundongos ou embriões de pintinhos, tem se mostrado eficiente para a modelagem da neovascularização. A CAM é uma membrana extraembrionária ricamente vascularizada, que apresenta imunorreatividade limitada, tornando-se um excelente modelo hospedeiro para transplantes de células de origem humana.
Este trabalho descreve a estratégia para enxertar organoides cerebrais humanos diferenciados em múltiplos estágios de maturação no MAC. A composição celular dos organoides cerebrais muda com o tempo, refletindo os marcos do desenvolvimento do cérebro humano. Nós enxertamos organoides cerebrais em estágios de maturação relevantes: expansão neuroepitelial (18 DIV), neurogênese precoce (60 DIV) e gliogênese precoce (180 DIV) na CAM de embriões embrionários dia (E)7 de galinha. Organoides cerebrais enxertados foram colhidos 5 dias depois e suas características histológicas foram analisadas.
Não foram detectados sinais histológicos de neovascularização nos organoides enxertados ou vasos sanguíneos anormais adjacentes aos enxertos. Além disso, mudanças marcantes foram observadas na composição celular dos organoides enxertados, a saber, um aumento no número de astrócitos gliais fibrilares ácidos-positivos-reativos. Entretanto, as alterações citoarquiteturais foram dependentes do estágio de maturação dos organoides. Em conjunto, esses resultados sugerem que organoides cerebrais podem crescer no MAC e mostram diferenças na citoarquitetura dependendo do estágio de maturação na enxertia.

Human brain organoids are an emerging technique that allows us to recapitulate the early development of the human brain in vitro1,2,3. Nevertheless, one of the major limitations of this model is the lack of vascularization, which plays indispensable roles not only in brain homeostasis but also in brain development4. In addition to the delivery of oxygen and nutrients, accumulating evidence suggests that the vascular system of the brain regulates neural differentiation, migration, and synaptogenesis during development5,6. Therefore, there is an urgent need to establish reliable models that can provide the missing vascular signaling and structure to brain organoids, enhancing the complexity of human brain organoid generation7.
Among the proposed methods for vascularization, two main streamlines can be considered: organoid engrafting into a living organism and purely in vitro technologies co-culturing endothelial cells and neural cells8,9,10,11,12. Intracerebral transplantation in mice is costly and time-consuming, making other technologies relevant for simpler models. The chick chorioallantoic membrane (CAM) assay has been used extensively to study angiogenesis13,14,15. In the last decade, several groups have successfully engrafted different types of organoids, including kidney16,17, cardiac18, and tumor organoids19,20, into CAMs. Nevertheless, little is known about the efficacy, toxicity/rejection, physiological effect, and methods to engraft human brain organoids into the CAM. Another interesting and yet unexplored aspect is the formation of a chimeric blood-brain barrier (BBB) between the CAM and the organoid astrocytic interface. Previous pioneering work suggested the putative feasibility of generating a BBB in the CAM by transplanting astrocytes and astrocyte-conditioned medium21,22,23. However, mature astrocytes seem to be unable to achieve this24,25. Thus, the astrocyte-induced formation of the BBB remains debatable, and transplanting human brain organoids would allow us to shed light on this controversy.
This video article describes a protocol for an in ovo human brain organoid transplant into CAM that promotes growth, improvement, and vascularization, resulting in organoids that encompass histologically compatible BBB elements. Here, we present a protocol ensuring the survival of the chicken embryo and report on the permissivity of the CAM to sustain brain organoid growth.

Autor em destaque: Otimizando o desenvolvimento neurovascular do organoide do cérebro humano em embrião de galinha

Modelagem Inicial de Nicho Neurovascular Organoide Cerebral Humano Não Guiado na Membrana Corioalantóide Permissiva do Embrião de Pinto

The key questions I aim to address revolve around the mechanisms and processes involving human brain formation in the context of normal development, as well as various pathological states. This includes investigating the factors influencing brain development, such as genetics, environmental, and epigenetic influences. Obtaining brain organoids that closely resemble the adult human brain, including vascularization, blood brain barrier functionality, the presence of microglia and cellular diversity is challenging.Overcoming this is essential for the development of more physiologically relevant brain organoid models that can efficiently mimic the adult human brain to enhance clinical applications. Through our research, we provide optimal conditions for transplanting human brain organoids into chorioallantoic membrane to ensure good development of the microglia. This clinical improvement is central for forthcoming efforts in the field to generate synthetic vascularized environment for brain organoids.The advantage of our protocol compared to other techniques lies in its high effectiveness and cost efficiency. We have achieved a high success rate in transplanting viable organoids using fertile eggs from farm chickens. In the future, our laboratory will focus on conducting functional assessments of neo vasculature associated with organoids, exploring potential use of this vascular design model for application of intravenous nanomedicine.Additionally, we aim to evaluate the biodistribution of these nanomedicines in the human central nervous system.

Seleção do cronograma de maturação do embrião para o transplante O experimento inicia-se em D0, quando os ovos fertilizados são incubados a 38 °C e 60% de umidade relativa. A membrana corioalantóide (MAC) é uma membrana extraembrionária altamente vascularizada que se desenvolve após a incubação dos ovos. É formado pela fusão do alantois e córion. Em D1, após 24 h de incubação, a câmara de ar é puncionada para impedir que a CAM se fixe à membrana interna do invólucro. A punção ...

Watch this Scientific Journal Video about Author Spotlight: Optimizing the Neurovascular Development of Human Brain Organoid in Chick Embryo at JoVE.com

Aqui, apresentamos um protocolo para enxertar organoides cerebrais humanos em múltiplos estágios de maturação na membrana corioalantóide (CAM) de pintinhos. Os organoides cerebrais foram cultivados seguindo protocolos padronizados não guiados.

Engrafting organoids into vascularized tissues in model animals, such as the immunodeficient mouse or chick embryo chorioallantoic membrane (CAM), has ...

As questões-chave que pretendo abordar giram em torno dos mecanismos e processos que envolvem a formação do cérebro humano no contexto do desenvolvimento normal, bem como vários estados patológicos. Isso inclui investigar os fatores que influenciam o desenvolvimento cerebral, como influências genéticas, ambientais e epigenéticas. A obtenção de organoides cerebrais que se assemelham ao cérebro humano adulto, incluindo vascularização, funcionalidade da barreira hematoencefálica, presença de micróglia e diversidade celular é um desafio.Superar isso é essencial para o desenvolvimento de modelos organoides cerebrais fisiologicamente mais relevantes que possam imitar eficientemente o cérebro humano adulto para melhorar as aplicações clínicas. Através de nossa pesquisa, fornecemos condições ideais para o transplante de organoides cerebrais humanos na membrana corioalantóica para garantir um bom desenvolvimento da microglia. Essa melhora clínica é fundamental para os próximos esforços no campo para gerar ambiente vascularizado sintético para organoides cerebrais.A vantagem do nosso protocolo em relação a outras técnicas reside na sua alta efetividade e custo-benefício. Alcançamos uma alta taxa de sucesso no transplante de organoides viáveis usando ovos férteis de galinhas de produção. No futuro, nosso laboratório se concentrará na realização de avaliações funcionais da neovasculatura associada a organoides, explorando o uso potencial deste modelo de desenho vascular para aplicação de nanomedicina intravenosa.Adicionalmente, objetivamos avaliar a biodistribuição desses nanofármacos no sistema nervoso central humano.

early-unguided-human-brain-organoid-neurovascular-niche-modeling-into

Research

JoVE Journal

Developmental Biology

Early Unguided Human Brain Organoid Neurovascular Niche Modeling into the Permissive Chick Embryo Chorioallantoic Membrane

Engrafting organoids into vascularized tissues in model animals, such as the immunodeficient mouse or chick embryo chorioallantoic membrane (CAM), has proven efficient for neovascularization modeling. The CAM is a richly vascularized extraembryonic membrane, which shows limited immunoreactivity, thus becoming an excellent hosting model for human origin cell transplants.
This paper describes the strategy to engraft human brain organoids differentiated at multiple maturation stages into the CAM. The cellular composition of brain organoids changes with time, reflecting the milestones of human brain development. We grafted brain organoids at relevant maturation stages: neuroepithelial expansion (18 DIV), early neurogenesis (60 DIV), and early gliogenesis (180 DIV) into the CAM of embryonic day (E)7 chicken embryos. Engrafted brain organoids were harvested 5 days later and their histological features were analyzed.
No histological signs of neovascularization in the grafted organoids or abnormal blood vessels adjacent to the graftings were detected. Moreover, remarkable changes were observed in the cellular composition of the grafted organoids, namely, an increase in the number of glial fibrillary acidic protein-positive-reactive astrocytes. However, the cytoarchitectural changes were dependent on the organoid maturation stage. Altogether, these results suggest that brain organoids can grow in the CAM, and they show differences in the cytoarchitecture depending on their maturation stage at grafting.

Here, we present a protocol to engraft human brain organoids at multiple maturation stages into the chick chorioallantoic membrane (CAM). Brain organoids were grown following unguided standardized protocols.