Contamos con el apoyo de la asistencia técnica experta del centro de citometría de flujo HSCI-CRM del Hospital General de Massachusetts y del centro Bauer Core de la Universidad de Harvard. T.K y K.G contaron con el apoyo del Consejo Sueco de Investigación y C.M. de la Fundación Alemana de Investigación. Agradecemos a Sergey Isaev e I-Hsiu Lee por su ayuda en el análisis de los datos de secuenciación de ARN de una sola célula.

Optimización del aislamiento de células estromales del timo y la médula ósea

<ol>
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D.T.S. es director y accionista de Agios Therapeutics y Editas Medicines; fundador, director, accionista y miembro del consejo asesor científico de Magenta Therapeutics y LifeVault Bio, accionista y fundador de Fate Therapeutics y Garuda Therapeutics, y director, fundador y accionista de Clear Creek Bio, consultor de FOG Pharma, Inzen Therapeutics y VCanBio, y receptor de fondos de investigación patrocinados por Sumitomo Dianippon. D.T.S y K.G son inventores de US20220143099A1 patentes.

Las células estromales de los órganos hematopoyéticos son fundamentales para la producción normal de sangre y las perturbaciones del estroma hematopoyético pueden dar lugar a graves deficiencias en el mantenimiento hematopoyético y en la respuesta al estrés 9,23,24. El conocimiento de las células estromales hematopoyéticas es esencial para la comprensión de las enfermedades hematológicas <...

En el adulto sano, la producción de novo de células sanguíneas se produce en la médula ósea y el timo. Las células estromales en estos sitios son esenciales para el mantenimiento de la hematopoyesis, pero el estroma constituye menos del 1% del tejido 1,2,3,4. Por lo tanto, la obtención de aislados puros de estroma portador de hematopoyesis constituye un desafío importante, particularmente para la multiómica unicelular que requiere un procesamiento oportuno para obtener muestras de alta calidad. Los componentes de diferentes cócteles de digestión pueden interferir con ciertos pasos en el análisis multiómico 5,6. Los protocolos presentados aquí detallan el aislamiento de una amplia variedad de células estromales de la médula ósea y los tejidos tímicos.
Las perturbaciones de los constituyentes estromales tanto en la médula ósea como en el timo dan lugar a una profunda alteración en el desarrollo de las células sanguíneas y pueden dar lugar a neoplasias malignas 7,8,9. El estroma portador de la hematopoyesis se daña después del condicionamiento citotóxico y el trasplante de médula ósea, lo que resulta en una reducción de la secreción de citocinas y factores de crecimiento que sostienen las células madre y progenitoras hematopoyéticas (HSPC)2,10,11. Además, el envejecimiento afecta a las células estromales de la médula ósea y el timo, lo que probablemente contribuya al envejecimiento de los fenotipos hematopoyéticos. El timo es el primer órgano que sufre una involución extensa asociada a la edad. La grasa y el tejido fibrótico comienzan a reemplazar al estroma de soporte de las células T desde el inicio de la pubertad12,13. En la médula ósea, el contenido de adipocitos aumenta con la edad y los nichos vascular y endosteal se remodelan significativamente 14,15,16.
Para permitir el estudio del estroma de soporte de hematopoyesis en múltiples estados de estrés y en el caso del timo tanto de tejido humano como murino, hemos optimizado los protocolos de digestión publicados anteriormente 1,2,8,17,18. Estos protocolos garantizan un aislamiento eficiente y reproducible de las células, y son compatibles con la secuenciación de ARN de una sola célula (scRNAseq) y otros tipos de multiómicas.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>0.25% Trypsin-EDTA</td>
			<td>Thermo Fisher Scientific</td>
			<td>25200-072</td>
			<td></td>
		</tr>
		<tr>
			<td>7AAD (7-aminoactinomycin D)</td>
			<td>BD Biosciences</td>
			<td>559925</td>
			<td></td>
		</tr>
		<tr>
			<td>Anti-Human Lineage Cocktail 3-FITC</td>
			<td>BD Biosciences</td>
			<td>643510</td>
			<td></td>
		</tr>
		<tr>
			<td>Bovine Serum Albumin</td>
			<td>Millipore Sigma</td>
			<td>A9647</td>
			<td></td>
		</tr>
		<tr>
			<td>C57Bl/6 mice</td>
			<td>Jackson</td>
			<td>664</td>
			<td>Males or females, 8-12 weeks old</td>
		</tr>
		<tr>
			<td>Calcein&#160;</td>
			<td>Fisher Scientific</td>
			<td>65-0853-78</td>
			<td></td>
		</tr>
		<tr>
			<td>Collagenase IV</td>
			<td>Millipore Sigma</td>
			<td>C5138</td>
			<td></td>
		</tr>
		<tr>
			<td>Corning Sterile Cell Strainers, White, Mesh Size: 70 &#181;m</td>
			<td>Fisher Scientific</td>
			<td>08-771-2</td>
			<td></td>
		</tr>
		<tr>
			<td>DAPI (4&#39;,6-Diamidino-2-Phenylindole, Dilactate)</td>
			<td>Biolegend</td>
			<td>422801</td>
			<td></td>
		</tr>
		<tr>
			<td>Dispase II</td>
			<td>Thermo Fisher Scientific</td>
			<td>17105041</td>
			<td></td>
		</tr>
		<tr>
			<td>Dnase I Solution</td>
			<td>Thermo Fisher Scientific</td>
			<td>90083</td>
			<td>&#160;2500 U/mL</td>
		</tr>
		<tr>
			<td>Easysep mouse streptavidin RapidSpheres Isolation kit</td>
			<td>StemCell Technologies</td>
			<td>19860</td>
			<td></td>
		</tr>
		<tr>
			<td>Fetal Bovine Serum</td>
			<td>Gibco</td>
			<td>A31605-01</td>
			<td>Qualified One Shot</td>
		</tr>
		<tr>
			<td>Human Fc Block</td>
			<td>BD Biosciences</td>
			<td>564220</td>
			<td></td>
		</tr>
		<tr>
			<td>Liberase TM&#160;</td>
			<td>Millipore Sigma</td>
			<td>5401127001</td>
			<td>Research Grade</td>
		</tr>
		<tr>
			<td>Medium 199</td>
			<td>Gibco</td>
			<td>12350</td>
			<td></td>
		</tr>
		<tr>
			<td>Mouse anti-human CD235a-BV77</td>
			<td>BD Biosciences</td>
			<td>740785</td>
			<td></td>
		</tr>
		<tr>
			<td>Mouse anti-human CD31-PE/Dazzle594</td>
			<td>Biolegend</td>
			<td>303130</td>
			<td></td>
		</tr>
		<tr>
			<td>Mouse anti-human CD45-BV77</td>
			<td>Biolegend</td>
			<td>304050</td>
			<td></td>
		</tr>
		<tr>
			<td>Mouse anti-human CD4-BV605</td>
			<td>BD Biosciences</td>
			<td>562658</td>
			<td></td>
		</tr>
		<tr>
			<td>Mouse anti-human CD66b-FITC</td>
			<td>BD Biosciences</td>
			<td>555724</td>
			<td></td>
		</tr>
		<tr>
			<td>Mouse anti-human CD8-APC/Cy7</td>
			<td>BD Biosciences</td>
			<td>557760</td>
			<td></td>
		</tr>
		<tr>
			<td>Mouse anti-human EpCam-BV421</td>
			<td>Biolegend</td>
			<td>324220</td>
			<td></td>
		</tr>
		<tr>
			<td>Protector RNase Inhibitor</td>
			<td>Millipore Sigma</td>
			<td>3335402001</td>
			<td></td>
		</tr>
		<tr>
			<td>Rat anti-mouse CD105-PE /dazzle594</td>
			<td>Biolegend</td>
			<td>120424</td>
			<td></td>
		</tr>
		<tr>
			<td>Rat anti-mouse CD11b-Biotin</td>
			<td>Biolegend</td>
			<td>101204</td>
			<td></td>
		</tr>
		<tr>
			<td>Rat anti-mouse CD140a-APC</td>
			<td>Fisher Scientific</td>
			<td>17-1401-81</td>
			<td></td>
		</tr>
		<tr>
			<td>Rat Anti-Mouse CD16/CD32 (Mouse BD Fc Block)</td>
			<td>BD Biosciences</td>
			<td>553142</td>
			<td></td>
		</tr>
		<tr>
			<td>Rat anti-mouse CD31-BUV737</td>
			<td>BD Biosciences</td>
			<td>612802</td>
			<td></td>
		</tr>
		<tr>
			<td>Rat anti-mouse CD31-BV421</td>
			<td>Biolegend</td>
			<td>102424</td>
			<td></td>
		</tr>
		<tr>
			<td>Rat anti-mouse CD3-Biotin</td>
			<td>Biolegend</td>
			<td>100244</td>
			<td></td>
		</tr>
		<tr>
			<td>Rat anti-mouse CD45.2-Biotin</td>
			<td>Biolegend</td>
			<td>109804</td>
			<td></td>
		</tr>
		<tr>
			<td>Rat anti-mouse CD45-PE/Cy7</td>
			<td>Biolegend</td>
			<td>103114</td>
			<td></td>
		</tr>
		<tr>
			<td>Rat anti-mouse CD45-PE/Cy7</td>
			<td>Biolegend</td>
			<td>103114</td>
			<td></td>
		</tr>
		<tr>
			<td>Rat anti-mouse CD45R/B220-Biotin</td>
			<td>Biolegend</td>
			<td>103204</td>
			<td></td>
		</tr>
		<tr>
			<td>Rat anti-mouse CD51-PE</td>
			<td>Biolegend</td>
			<td>104106</td>
			<td></td>
		</tr>
		<tr>
			<td>Rat anti-mouse EpCam-BV711</td>
			<td>BD Biosciences</td>
			<td>563134</td>
			<td></td>
		</tr>
		<tr>
			<td>Rat anti-mouse Ly-6A/E(Sca-1)-AF700</td>
			<td>Biolegend</td>
			<td>108142</td>
			<td></td>
		</tr>
		<tr>
			<td>Rat anti-mouse Ly-6G/Ly-6C(Gr1)-Biotin</td>
			<td>Biolegend</td>
			<td>108404</td>
			<td></td>
		</tr>
		<tr>
			<td>Rat anti-mouse Ter119-Biotin</td>
			<td>Biolegend</td>
			<td>116204</td>
			<td></td>
		</tr>
		<tr>
			<td>Rat anti-mouse Ter119-PE</td>
			<td>Biolegend</td>
			<td>116208</td>
			<td></td>
		</tr>
		<tr>
			<td>Rat anti-mouse Ter119-PE/Cy7</td>
			<td>Biolegend</td>
			<td>116222</td>
			<td></td>
		</tr>
		<tr>
			<td>Stemxyme&#160;</td>
			<td>Worthington Biochemical</td>
			<td>LS004107</td>
			<td></td>
		</tr>
	</tbody>
</table>

stromal cell isolation from hematopoietic organs

La secuenciación unicelular ha permitido el mapeo de poblaciones celulares heterogéneas en el estroma de los órganos hematopoyéticos. Estas metodologías proporcionan una lente a través de la cual estudiar la heterogeneidad no resuelta previamente en estado estacionario, así como los cambios en la representación del tipo de célula inducidos por tensiones extrínsecas o durante el envejecimiento. Aquí, presentamos protocolos paso a paso para el aislamiento de poblaciones de células estromales de alta calidad de timo murino y humano, así como de hueso murino y médula ósea. Las celdas aisladas a través de estos protocolos son adecuadas para generar conjuntos de datos multiómicos de una sola celda de alta calidad. Aquí se analizan los impactos de la digestión de la muestra, el agotamiento del linaje hematopoyético, el análisis/clasificación FACS y cómo estos factores influyen en la compatibilidad con la secuenciación de una sola célula. Con ejemplos de perfiles FACS que indican una disociación exitosa e ineficiente y rendimientos de células estromales aguas abajo en el análisis posterior a la secuenciación, se proporcionan indicadores reconocibles para los usuarios. Tener en cuenta los requisitos específicos de las células estromales es crucial para obtener resultados reproducibles y de alta calidad que puedan avanzar en el conocimiento en el campo.

In the healthy adult, de novo production of blood cells occurs in the bone marrow and the thymus. Stromal cells at these sites are essential for maintenance of hematopoiesis, but stroma constitutes less than 1% of the tissue1,2,3,4. Obtaining pure isolates of hematopoiesis supporting stroma therefore constitutes a significant challenge, particularly for single-cell multiomics that requires expedient processing to obtain samples of high quality. Components of different digestion cocktails may interfere with certain steps in multiomics analysis5,6. The protocols presented here detail the isolation of a wide variety of stromal cells from bone marrow and thymic tissues.
Perturbations of stromal constituents in both bone marrow and thymus result in profound disruption in blood cell development and can result in malignancies7,8,9. Hematopoiesis supporting stroma is damaged following cytotoxic conditioning and bone marrow transplantation, resulting in reduced secretion of cytokines and growth factors that sustain hematopoietic stem and progenitor cells (HSPCs)2,10,11. Furthermore, aging affects bone marrow and thymus stromal cells likely contributing to aged hematopoietic phenotypes. The thymus is the first organ to undergo extensive age-associated involution. Fat and fibrotic tissue start replacing T cell supportive stroma as early as the onset of puberty12,13. In the bone marrow, adipocyte content increases with age and the vascular and endosteal niches are significantly remodeled14,15,16.
To enable study of hematopoiesis supportive stroma across multiple stress states and in the case of the thymus of both human and murine tissue, we have optimized previously published digestion protocols1,2,8,17,18. These protocols ensure efficient and reproducible isolation of cells, and they are compatible with single-cell RNAsequencing (scRNAseq) and other types of multiomics.

Autor destacado: Avance de la investigación hematopoyética mediante el aislamiento de células estromales para la secuenciación de células individuales

Aislamiento de células estromales de órganos hematopoyéticos

Development of hematic cells in bone marrow and thymus is highly dependent on stromal cells for support. Perturbations of hematopoietic stromal cell function can lead to inefficient or even malignant blood production. Our lab is focused on understanding stromal cell regulation of hematopoiesis and how it can be manipulated for therapeutic benefits.The advent of single cell sequencing has driven a cascade of recent advances in many research fields. This is also the case in our field where single cell resolution has enabled the identification of heterogeneous stromal cell populations in hematopoietic organs that were previously unknown. Our protocols are optimized to address this, and we hope they will enable more research on stromal cells to tackle critical questions in the field.

Estos protocolos producen variedades de células estromales reproducibles del timo y la médula ósea adecuadas para el análisis de citometría de flujo, así como multiómicas de una sola célula, como la secuenciación de SCRNA. El tejido tímico murino experimenta una remodelación significativa en respuesta a factores estresantes, como el condicionamiento citotóxico que precede al trasplante de médula ósea o el proceso natural de envejecimiento. Como consecuencia, la celularidad tímica se reduce drásticamente e...

Watch this Scientific Journal Video about Stromal Cell Isolation From Hematopoietic Organs at JoVE.com

Aquí presentamos protocolos que permiten el aislamiento de células estromales de hueso murino, médula ósea, timo y tejido tímico humano compatible con multiómicas unicelulares.

Single-cell sequencing has enabled the mapping of heterogeneous cell populations in the stroma of hematopoietic organs. These methodologies provide a lens ...

El desarrollo de células hemáticas en la médula ósea y el timo depende en gran medida de las células estromales para su soporte. Las perturbaciones de la función de las células estromales hematopoyéticas pueden conducir a una producción de sangre ineficiente o incluso maligna. Nuestro laboratorio se centra en comprender la regulación de la hematopoyesis por parte de las células estromales y cómo se puede manipular para obtener beneficios terapéuticos.El advenimiento de la secuenciación de células individuales ha impulsado una cascada de avances recientes en muchos campos de investigación. Este es también el caso en nuestro campo, donde la resolución de células individuales ha permitido la identificación de poblaciones heterogéneas de células estromales en órganos hematopoyéticos que antes eran desconocidas. Nuestros protocolos están optimizados para abordar esto, y esperamos que permitan más investigaciones sobre las células estromales para abordar preguntas críticas en el campo.

stromal-cell-isolation-from-hematopoietic-organs

Research

JoVE Journal

Immunology and Infection

Stromal Cell Isolation From Hematopoietic Organs

731 vistas.  Massachusetts General Hospital. El desarrollo de células hemáticas en la médula ósea y el timo depende en gran medida de las células estromales para su soporte. Las perturbaciones de la función de las células estromales hematopoyéticas pueden conducir a una producción de sangre ineficiente o incluso maligna. Nuestro laboratorio se centra en comprender la regulación de la hematopoyesis por parte de las células estromales y cómo se puede manipular para obtener beneficios terapéuticos.El advenimiento de la ...

Video: Autor destacado: Avance de la investigación hematopoyética mediante el aislamiento de células estromales para la secuenciación de células individuales

Single-cell sequencing has enabled the mapping of heterogeneous cell populations in the stroma of hematopoietic organs. These methodologies provide a lens through which to study previously unresolved heterogeneity at steady state, as well as changes in cell type representation induced by extrinsic stresses or during aging. Here, we present step-wise protocols for the isolation of high-quality stromal cell populations from murine and human thymus, as well as murine bone and bone marrow. Cells isolated through these protocols are suitable for generating high-quality single-cell multiomics datasets. The impacts of sample digestion, hematopoietic lineage depletion, FACS analysis/sorting, and how these factors influence compatibility with single-cell sequencing are discussed here. With examples of FACS profiles indicating successful and inefficient dissociation and downstream stromal cell yields in post-sequencing analysis, recognizable pointers for users are provided. Considering the specific requirements of stromal cells is crucial for acquiring high-quality and reproducible results that can advance knowledge in the field.

Here we present protocols that enable isolation of stromal cells from murine bone, bone marrow, thymus and human thymic tissue compatible with single-cell multiomics.

Investigación

Inmunología e Infección

Isolation of Stromal Cells from Murine Thymic Tissue for Generating High&#45;Quality Single Cell Multiomics Datasets

To begin, position the euthanized mouse on a surgical platform and open the chest cavity. Using surgical scissors, make a transverse incision below the rib cage and cut ribs on each side of the mouse to the clavicle. Then cut the diaphragm to release the chest wall And lift ribs with forceps to expose the thoracic cavity.Hold the thymus with forceps, and gently cut the connective tissue holding the thymus in place. To perform enzymatic dissociation of murine thymic tissue, place the cleaned thymus in a 15 milliliter tube cap and use sterile surgical scissors to finely mince the tissue. Add two milliliters of murine dissociation cocktail to the tube.Attach the cap containing the thymus pieces and invert the tube five times to re-suspend the tissue. Wrap the tube cap in paraffin film. After incubation, place the tube in a rack and allow the tissue to settle.Remove the supernatant and pass it over a 70 micrometer cell strainer into a 50 milliliter ice cold tube. Then, add 20 milliliters of M1 99 with 2%FBS medium to the cell suspension. Centrifuge the tube at 500 G for five minutes at four degrees Celsius.After discarding the supernatant, re-suspend the pellet in M1 99 and 2%FBS medium.

Aislamiento de células estromales a partir de tejido tímico murino para generar conjuntos de datos multiómicos de células individuales de alta calidad

Stromal Cell Extraction from Mouse Bone and Bone Marrow for Superior Single Cell Multi&#45;Omics Data

To begin, take the femur, tibia, pelvis, and humerus bones isolated from a mouse. Use a scalpel to cut through the growth plates of long bones, removing the epiphysis. Place it in a 10-centimeter dish with M199 medium plus 2%FBS on ice.Next, use a 28-gauge needle and a 10-milliliter syringe filled with M199 medium plus 2%FBS to flush the marrow into a 15-milliliter tube on ice. Place the flushed bone in the dish with the epiphysis. Leave the 15-milliliter tube upright on ice until the marrow settles.Then remove the M199 medium plus 2%FBS Add four milliliters of the B&M dissociation cocktail to the 15-milliliter tube and incubate in a 37 degree Celsius water bath. After incubation, collect the supernatant and filter through a 70-micrometer cell strainer into a cold 50-milliliter tube. Add two milliliters of fresh B&M dissociation cocktail to the remaining bone marrow pellet and return it to the water bath.Using a one-milliliter pipette, vigorously pipette any remaining bone marrow pieces. Collect all cell suspension in the same tube as before. Add 20 milliliters of M199 medium with 0.5%BSA, and two-millimolar EDTA to the cell suspension.Afterward, centrifuge the cells at 500 G for five minutes at four degrees Celsius. Resuspend the pellet in 500 microliters of PBS with a 0.5%BSA and biotin antibodies. Incubate on an orbital shaker for 10 minutes at room temperature in the dark.Next, vortex the magnetic beads thoroughly. Add 25 microliters of the beads to the tube and incubate again on the orbital shaker. Place the tube in a matching magnet for two to three minutes and collect the supernatant in a fresh tube.Break the bones into smaller pieces in the 10-centimeter dish using the flat cap end of a 50-milliliter tube. Filter the supernatant through a 70-micrometer cell strainer to isolate bone fragments. Cut the bone fragments in the cell strainer with scissors.Place the filter with the bone fragments on a 50-milliliter tube and open the filter with the scalpel. With tweezers, transfer the bone fraction to five milliliters of murine B&M dissociation mix. Then place the tube horizontally in a 37 degree Celsius water bath with 120 RPM shaking for 30 minutes.After digestion, add 25 milliliters of M199 medium with 0.5%BSA and two-millimolar EDTA. Filter the supernatant containing stromal cells through a 70-micron cell strainer into a cold 50-milliliter tube.