Agradecemos a L. Douay y MC Giarratana (Universidad de París VI, Francia) para el asesoramiento en la diferenciación eritroide ex vivo, D. Allan H. y Atkins (OHRI, Canadá) para proporcionar muestras de sangre (obtenida en el Hospital de Ottawa de Ética de Investigación de la Junta # 2007804-01H), D. Trono (Ecole Polytechnique Federale de Lausanne) para proporcionar a los vectores lentiviral y FJ Dilworth (OHRI, Canadá) para la lectura crítica del manuscrito. Este proyecto fue financiado por una subvención CIHR (MOP-82813) para MBCGP es un beneficiario de una investigación Ontario Fondo Computacional Becas de Formación Postdoctoral Regulomics. MB titular de la Cátedra de Investigación de Canadá en el Reglamento de la expresión génica.

<ol>
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C., De Harven, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Erythrocytic+maturation+in+vitro+of+murine+(Friend)+virus-induced+leukemic+cells.">Erythrocytic maturation in vitro of murine (Friend) virus-induced leukemic cells.</a> Natl Cancer Inst Monogr. 22, 505-522 (1966).</li><li>Weiss, M. J., Yu, C., Orkin, S. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Erythroid-cell-specific+properties+of+transcription+factor+GATA-1+revealed+by+phenotypic+rescue+of+a+gene-targeted+cell+line.">Erythroid-cell-specific properties of transcription factor GATA-1 revealed by phenotypic rescue of a gene-targeted cell line.</a> Mol Cell Biol. 17, 1642-1651 (1997).</li><li>Lozzio, B. B., Lozzio, C. B., Bamberger, E. G., Feliu, A. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+multipotential+leukemia+cell+line+(K-562)+of+human+origin.">A multipotential leukemia cell line (K-562) of human origin.</a> Proc Soc Exp Biol Med. 166, 546-550 (1981).</li><li>Giarratana, 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=Ex+vivo+generation+of+fully+mature+human+red+blood+cells+from+hematopoietic+stem+cells.">Ex vivo generation of fully mature human red blood cells from hematopoietic stem cells.</a> Nat Biotechnol. 23, 69-74 (2005).</li><li>Salmon, P., Trono, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Production+and+titration+of+lentiviral+vectors.">Production and titration of lentiviral vectors.</a> Curr Protoc Neurosci. Chapter 4, (2006).</li><li>Chao, M. P., Seita, J., Weissman, I. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Establishment+of+a+normal+hematopoietic+and+leukemia+stem+cell+hierarchy.">Establishment of a normal hematopoietic and leukemia stem cell hierarchy.</a> Cold Spring Harb Symp Quant Biol. 73, 439-449 (2008).</li><li>Amsellem, S., Ravet, E., Fichelson, S., Pflumio, F., Dubart-Kupperschmitt, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Maximal+lentivirus-mediated+gene+transfer+and+sustained+transgene+expression+in+human+hematopoietic+primitive+cells+and+their+progeny.">Maximal lentivirus-mediated gene transfer and sustained transgene expression in human hematopoietic primitive cells and their progeny.</a> Mol Ther. 6, 673-677 (2002).</li><li>Laurenti, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Inducible+gene+and+shRNA+expression+in+resident+hematopoietic+stem+cells+in+vivo.">Inducible gene and shRNA expression in resident hematopoietic stem cells in vivo.</a> Stem Cells. 28, 1390-1398 (2010).</li><li>Palii, C. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Differential+genomic+targeting+of+the+transcription+factor+TAL1+in+alternate+haematopoietic+lineages.">Differential genomic targeting of the transcription factor TAL1 in alternate haematopoietic lineages.</a> EMBO J. 30, 494-509 (2011).</li><li>Fibach, E., Manor, D., Oppenheim, A., Rachmilewitz, E. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Proliferation+and+maturation+of+human+erythroid+progenitors+in+liquid+culture.">Proliferation and maturation of human erythroid progenitors in liquid culture.</a> Blood. 73, 100-103 (1989).</li><li>Wada, H. <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+major+blood+group+antigens+on+human+erythroid+cells+in+a+two+phase+liquid+culture+system.">Expression of major blood group antigens on human erythroid cells in a two phase liquid culture system.</a> Blood. 75, 505-511 (1990).</li><li>Sui, X. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Erythropoietin-independent+erythrocyte+production:+signals+through+gp130+and+c-kit+dramatically+promote+erythropoiesis+from+human+CD34++cells.">Erythropoietin-independent erythrocyte production: signals through gp130 and c-kit dramatically promote erythropoiesis from human CD34+ cells.</a> J Exp Med. 183, 837-845 (1996).</li><li>Panzenbock, B., Bartunek, P., Mapara, M. Y., Zenke, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Growth+and+differentiation+of+human+stem+cell+factor/erythropoietin-dependent+erythroid+progenitor+cells+in+vitro.">Growth and differentiation of human stem cell factor/erythropoietin-dependent erythroid progenitor cells in vitro.</a> Blood. 92, 3658-3668 (1998).</li><li>Lindern, M. v. o. n. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+glucocorticoid+receptor+cooperates+with+the+erythropoietin+receptor+and+c-Kit+to+enhance+and+sustain+proliferation+of+erythroid+progenitors+in+vitro.">The glucocorticoid receptor cooperates with the erythropoietin receptor and c-Kit to enhance and sustain proliferation of erythroid progenitors in vitro.</a> Blood. 94, 550-559 (1999).</li><li>Freyssinier, J. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=amplification+and+characterization+of+a+population+of+human+erythroid+progenitors.">amplification and characterization of a population of human erythroid progenitors.</a> Br J Haematol. 106, 912-922 (1999).</li><li>Malik, P. <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+vitro+model+of+human+red+blood+cell+production+from+hematopoietic+progenitor+cells.">An in vitro model of human red blood cell production from hematopoietic progenitor cells.</a> Blood. 91, 2664-2671 (1998).</li><li>Carlile, G. W., Smith, D. H., Wiedmann, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Caspase-3+has+a+nonapoptotic+function+in+erythroid+maturation.">Caspase-3 has a nonapoptotic function in erythroid maturation.</a> Blood. 103, 4310-4316 (2004).</li><li>Mazurier, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Rapid+analysis+and+efficient+selection+of+human+transduced+primitive+hematopoietic+cells+using+the+humanized+S65T+green+fluorescent+protein.">Rapid analysis and efficient selection of human transduced primitive hematopoietic cells using the humanized S65T green fluorescent protein.</a> Gene Ther. 5, 556-562 (1998).</li><li>Salmon, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High-level+transgene+expression+in+human+hematopoietic+progenitors+and+differentiated+blood+lineages+after+transduction+with+improved+lentiviral+vectors.">High-level transgene expression in human hematopoietic progenitors and differentiated blood lineages after transduction with improved lentiviral vectors.</a> Blood. 96, 3392-3398 (2000).</li></ol>

Una serie de métodos se han utilizado previamente para diferenciar las células eritroides en la cultura, con grados variables de éxito. Por ejemplo, algunos protocolos, sin co-cultivo de MS-5 permite la expansión de las células eritroides, pero no son eficientes en la producción de células completamente maduros enucleados rojos 12-17. Mientras que otros métodos permiten la enucleación eficiente, es a expensas de la proliferación de 18,19. El método que hemos utilizado aquí, inicialmente...

lentiviral-mediated knockdown during ex vivo erythropoiesis of human hematopoietic stem cells

La eritropoyesis es un sistema modelo utilizado para estudiar la diferenciación celular. Durante la eritropoyesis, pluripotentes humanas adultas células madre hematopoyéticas (HSC) se diferencian en células progenitoras oligopotent, precursores comprometidos y los glóbulos rojos maduros 1. Este proceso está regulado en gran parte a nivel de la expresión génica, en el que factores de transcripción específicos del linaje activar genes específicos, mientras que simultáneamente la represión de los genes que son específicos para otros tipos de células 2. Los estudios sobre factores de transcripción que regula la eritropoyesis se realizan a menudo con líneas celulares humanas y murinas que representan, en cierta medida, las células eritroides en las etapas de diferenciación dado 5.3. Sin embargo, líneas de células transformadas pueden imitar sólo parcialmente las células eritroides y lo más importante no permitir que un estudio de forma comprensible los cambios dinámicos que ocurren cuando las células de los avances a través de muchas etapas hacia su último destino eritroides. Por lo tanto, un reto actual sigue siendo el desarrollo de un protocolo para obtener una población relativamente homogénea de las CMH primario y las células eritroides en las diversas etapas de diferenciación en cantidades que sean suficientes para llevar a cabo la genómica y la proteómica experimentos. A continuación se describe una célula de ex vivo protocolo de cultivo para inducir la diferenciación eritroide de hematopoyéticas humanas células madre / progenitoras que han sido aislados de sangre del cordón umbilical o de médula ósea o sangre periférica movilizada para adultos con G-CSF (aféresis). Este sistema de cultivo, inicialmente desarrollado por el laboratorio de Douay 6, utiliza las citocinas y la cultura co-en las células mesenquimales para imitar el microambiente de la médula ósea. El uso de este protocolo de diferenciación in vivo ex, se observa una fuerte amplificación de los progenitores eritroides, la inducción de diferenciación exclusivamente hacia el linaje eritroide y una maduración completa a la etapa de enucleado los glóbulos rojos. Así, este sistema ofrece la oportunidad de estudiar el mecanismo molecular de la regulación transcripcional de las células madre hematopoyéticas progreso a lo largo del linaje eritroide. El estudio de la eritropoyesis en el nivel de la transcripción también se requiere la capacidad de los factores específicos de más de expresar o una caída en la enseñanza primaria las células eritroides. Para ello, se utiliza un sistema de genes lentivirus mediada por la entrega que permite que la infección eficiente de la división y que no se dividen las células 7. Aquí mostramos que somos capaces de caída de manera eficiente la TAL1 factor de transcripción en células primarias de eritroides humanos. Además, la expresión de GFP demuestra una eficiencia de la infección por lentivirus cerca del 90%. Por lo tanto, el protocolo ofrece un sistema muy útil para la caracterización de la red de regulación de factores de transcripción que la eritropoyesis control.

Watch this Scientific Journal Video about Lentiviral-mediated Knockdown During Ex Vivo Erythropoiesis of Human Hematopoietic Stem Cells at JoVE.com

Lentiviral-mediated Knockdown During Ex Vivo Erythropoiesis of Human Hematopoietic Stem Cells

Un<em&gt; Ex vivo</em&gt; Protocolo para generar células maduras de la sangre humana rojo de madre hematopoyéticas / progenitores se describe. Además se describe una eficiente entrega lentiviral método para derribar el TAL1 factor de transcripción en las células eritroides primaria. La eficiencia de la administración de genes mediada por lentivirus se demuestra el uso de virus que expresan GFP.

Lentiviral mediada por derribo Durante Ex Vivo Eritropoyesis de las células estaminales hematopoyéticas

Erythropoiesis is a commonly used model system to study cell differentiation. During erythropoiesis, pluripotent adult human hematopoietic stem cells ...

lentiviral-mediated-knockdown-during-ex-vivo-erythropoiesis-human

Research

JoVE Journal

Biology

Lentiviral-mediated Knockdown During Ex Vivo Erythropoiesis of Human Hematopoietic Stem Cells

13.1K vistas.  Ottawa Hospital Research Institute. Un Ex vivo Protocolo para generar células maduras de la sangre humana rojo de madre hematopoyéticas / progenitores se describe. Además se describe una eficiente entrega lentiviral método para derribar el TAL1 factor de transcripción en las células eritroides primaria. La eficiencia de la administración de genes mediada por lentivirus se demuestra el uso de virus que expresan GFP.

Video: Lentiviral-mediated Knockdown During Ex Vivo Erythropoiesis of Human Hematopoietic Stem Cells

Isolation and Transplantation of Hematopoietic Stem Cells (HSCs)

Isolation and Transplantation of Hematopoietic Stem Cells HSCs

I am Christina Ceso. I am a postdoc in David's Den lab and I work on the hematopoietic stem cells. Today we are going to purify long-term recuperating hematopoietic stem cells and we'll transplant them into a mouse.We start by spraying the mice with alcohol so that first of all, the mind starts sterilized and also the hair doesn't interfere with the dissection. We use PBS with 2%serum for the dissection. I cut the back skin and I pull the skin apart in order to expose the tissue.In order to isolate the tibia, I hold the tibia with tweezers. I cut the tendon on top of the knee and I cut the muscles below the knee and after that I cut through the knee so that the TBI is not connected to the rest of the limb anymore and I pull in order to isolate it. I then hold the TB upside down and with the scissors I separate the foot from the tibia In order to obtain the femur.I cut the muscles around the femur and then I dislocate the femur from the hip. In order to isolate the hip, I cut the muscle around the hip bone on the side of the tail of the mouse and then I pull the hip away from the body of the mouth In order to isolate the spine. I cut through the tail as close as I can to the beginning of the back and then I cut on the two sides of the spine and below the spine, trying to stay as close as possible to the spine so that the peritoneum is not cut and the intestine is left untouched.A first round of cleaning of the bones is done with a scalpel, which is used to scrape the bone, the muscles away from the bone. The scalpel is good to clean the femurs, the hip and the spine. In order to clean the tibia, I hold them with forceps and I use the forceps to remove as much tissue as possible.A second round of cleaning is done using clean wipe to completely clean the bones outta the muscle, and I use the F wipe to clean the tibia, the femurs and the hips. So this is how bones look. After cleaning, I prefer 50 amount tubes with filters on top and I transfer the bones into the mortar.I add the section media and I crush the bones ask of the first round of crashing of the bones. I piped the mixture in order to release as many styles as possible into solution and reduce clumps. I transferred the mixture on the tubes through the filters and this is what the bone fragments look like after the first round of crushing.So I add more dissection medium to the bone fragments and I flash them again. I transferred the seline mixture to the tubes through the filters and at this point the remaining bone fragments are white and there is no bone marrow left. The tubes are filled with PBS 2%serum and in order to have them all with the same weight so that they're balanced in the centrifuge, but also in order to wash the filters so that we obtain as many cells as possible, I then centrifuge the cell mixture and after centrifugation, the palt includes the bone marrow cells.I aspirate the medium and I move back and forward the tube on the rack so that the pelle is becomes loose and fewer clamps are formed. When I add medium, at this point I add one ml of medium per tube and I ics since I'm sorting hematopoietic stem cells. Later on, I'm going to store an ALI output of total bone marrow sizes at this point, which I will use later for the fact single color control.I add lineage antibody cocktail. I ordered the samples to mix them well and I invaded four degrees for 15 minutes. In the meantime, I start preparing the columns for the lineage division.I put the columns on the magnet and I prepare Ian tubes under the columns. I also prepared the gas PBS using aster flip filter and attaching it to the vacuum so that all the bubbles of air move in the top part of the filter. I then add three ml of the gas DBS to each column in order for the column to become wet.After the incubation with the antibodies, I add medium to the cell samples and I centrifuge them in order to remove the excess of antibodies. After the centrifugation, the stain cells are in the pallet. I aspirate the medium and I suspend the pallet in one mile of the gas PBSI Add the strip tab beans, I mix the cells and I incubate for 15 minutes at four degrees.After the incubation, I put new elucian tubes under the columns. I add two ml of PBS to each tube with the cells and I transferred the cell mixture to the column through a 40 micron filter. I wash the tubes with more medium in order to collect all the cells remaining and I apply the remaining medium through the filters to the columns.The progenitor cells lineage low are alluded into the collection views. I pulled the luted samples and I sent tofu them. So after the centrifugation, the depleted cells are in a white pate.I aspirate the medium and re suspend the cells. I store an adequate of the depleted cells and I add the antibodies to the cell mixture for the sorting and also to all the single color controls. The antibodies are incubated in that with the size for 15 minutes in the fridge.After the ation, I add medium to the cells and and centrifuge them to remove the ex excess of antibodies. After the centrifugation, the cells are in the pt, I aspirate the media that I suspend the cells and I transfer the cells into fox tubes with a blue filter. At this point, the cells are ready to be sorted.I place, I place the mouse under a heating lamp for a few minutes so that the veins dilate and they are more easily seen. When preparing the syringe, you have to be careful to eliminate all the bubbles from the, the mixture that is in the syringe and then you bend the needle at 90 degrees. I put the mouse under a glass cup with a weight on top so that it can run away.I sterilize the tail with the alcohol pad so that the site of injection is sterile, but also it's easier to identify the vein. If you look at the tail of the mouse from the top in the middle and top of the tail, there is an artery while on the two sides there are the two veins and we inject the cells in one of the two veins. I insert the needle into the vein and I inject following injection.It is to wait for a couple of seconds before removing the needle, the needle, and after that I clean the side of injection. This is a representation of the syringe with the ben needle bent at 90 degrees with the knee, the at this ankle compared to the tail, which makes the injection the easiest. When you injecting the tail of the mouse, you have to keep in mind that the tail vein is extremely superficial, so really this is the orientation of the needle compared to the tail.And it looks like you will just keep sliding on top of the tail, but actually you will get into the tail then. I am Christina Ceso. I am a post in David Kaden lab, and I work on the hematopoietic stem cells.I usually use for animals to start with, and I had more variability at the beginning, but once you become consistent with your methods, I consistently get about 50, 000 to 60, 000 stem cells out for mice. I did my PhD in London with Dr.Fiona Wat working on derma stem cells. After that, I just wanted to have a wider knowledge of adult stem cells in various tissues, and so I decided to move to David Kaden lab to work on hematopoietic stem cells, mainly because the things that are known about hematopoietic stem cells are the things that are not known for the epidermic stem cells and a number of assays that can be done with epi.Epidermal stem cells are not really done yet with the hematopoietic stem cells, and so at this point I'm trying to put together the, the knowledge from the two different fields and ultimately I'm interested in the study of the mechanism to regulate adult tissue sensors in general, so not just the epidermis or the stem cells, but also different tissues because there are, there are similar mechanism that is, it's always the same genes that are involved in the regulation that just interact with each other in different ways, and it's just interesting to understand what makes each stem cell be a stem, but then ultimately a stem cell in a different tissue. So giving rise to a different protein.

Aislamiento y trasplante de células madre hematopoyéticas (HSC)

Investigación

Biología

Derivation of Hematopoietic Stem Cells from Murine Embryonic Stem Cells

A stem cell is defined as a cell with the capacity to both self-renew and generate multiple differentiated progeny.  Embryonic stem cells (ESC) are derived from the blastocyst of the early embryo and are pluripotent in differentiative ability.  Their vast differentiative potential has made them the focus of much research centered on deducing how to coax them to generate clinically useful cell types.  The successful derivation of hematopoietic stem cells (HSC) from mouse ESC has recently been accomplished and can be visualized in this video protocol.  HSC, arguably the most clinically exploited cell population, are used to treat a myriad of hematopoietic malignancies and disorders.  However, many patients that might benefit from HSC therapy lack access to suitable donors.  ESC could provide an alternative source of HSC for these patients.  The following protocol establishes a baseline from which ESC-HSC can be studied and inform efforts to isolate HSC from human ESC.  In this protocol, ESC are differentiated as embryoid bodies (EBs) for 6 days in commercially available serum pre-screened for optimal hematopoietic differentiation.  EBs are then dissociated and infected with retroviral HoxB4.  Infected EB-derived cells are plated on OP9 stroma, a bone marrow stromal cell line derived from the calvaria of  M-CSF-/- mice, and co-cultured in the presence of hematopoiesis promoting cytokines for ten days.  During this co-culture, the infected cells expand greatly, resulting in the generation a heterogeneous pool of 100s of millions of cells.  These cells can then be used to rescue and reconstitute lethally irradiated mice.

This protocol details the derivation of transplantable hematopoietic stem cells from mouse embryonic stem cells (ESC) and their subsequent injection into lethally irradiated recipient mice. Briefly, ESC are differentiated as embryoid bodies, which are then infected with retroviral HoxB4 and co-cultured with OP9 stromal cells and hematopoietic cytokines.

Derivación de células madre hematopoyéticas de células madre embrionarias murinas

A stem cell is defined as a cell with the capacity to both self-renew and generate multiple differentiated progeny.  Embryonic stem cells (ESC) are ...

Counting Human Neural Stem Cells

Knowledge of the exact number of viable cells in a given volume of a cell suspension is required for many routine tissue culture manipulations, such as plating cells for immunocytochemistry or for cell transfections. This protocol describes a straightforward and fast method for differentiating between live and dead cells and quantifying the cell concentration and total cell number using a hemacytometer. This procedure first requires detaching cells from a growth surface and resuspending them in media. Next, the cells are diluted in a solution of Trypan blue (ideally to a concentration that will give 20-50 cells per quadrant) and placed in the hemacytometer. Finally, averaging the counts of viable cells in several randomly selected quadrants, dividing the average by the volume of one 1 mm2 quadrant (0.1 &mu;l) and multiplying by the dilution factor gives the number of cells per l. Multiplying this cell concentration by the total volume in &mu;l gives the total cell number. This protocol describes counting human neural stem/precursor cells (hNSPCs), but can also be used for many other cell types.

Knowledge of the exact number of viable cells is required for many tissue culture manipulations. This protocol describes how to differentiate between live and dead cells and quantify cells using a hemacytometer. Although it describes counting human neural stem/precursor cells (hNSPCs), it can be used for other cell types.

Conteo de células madre neurales humanas

Knowledge of the exact number of viable cells in a given volume of a cell suspension is required for many routine tissue culture manipulations, such as ...

Isolation and Analysis of Hematopoietic Stem Cells from the Placenta

Hematopoietic stem cells (HSCs) have the ability to self-renew and generate all cell types of the blood lineages throughout the lifetime of an individual. All HSCs emerge during embryonic development, after which their pool size is maintained by self-renewing cell divisions. Identifying the anatomical origin of HSCs and the critical developmental events regulating the process of HSC development has been complicated as many anatomical sites participate during fetal hematopoiesis. Recently, we identified the placenta as a major hematopoietic organ where HSCs are generated and expanded in unique microenvironmental niches (Gekas, et al 2005, Rhodes, et al 2008). Consequently, the placenta is an important source of HSCs during their emergence and initial expansion.
In this article, we show dissection techniques for the isolation of murine placenta from E10.5 and E12.5 embryos, corresponding to the developmental stages of initiation of HSCs and the peak in the size of the HSC pool in the placenta, respectively. In addition, we present an optimized protocol for enzymatic and mechanical dissociation of placental tissue into single-cell suspension for use in flow cytometry or functional assays. We have found that use of collagenase for single-cell suspension of placenta gives sufficient yields of HSCs. An important factor affecting HSC yield from the placenta is the degree of mechanical dissociation prior to, and duration of, enzymatic treatment.
We also provide a protocol for the preparation of fixed-frozen placental tissue sections for the visualization of developing HSCs by immunohistochemistry in their precise cellular niches. As hematopoietic specific antigens are not preserved during preparation of paraffin embedded sections, we routinely use fixed frozen sections for localizing placental HSCs and progenitors.

We have identified the placenta as a major hematopoietic organ during development. We found that hematopoietic stem cells (HSCs) are both generated and expanded in the placenta in unique microenvironmental niches. Here, we describe experimental techniques required for isolation and visualization of HSCs in the mouse placenta.

Aislamiento y análisis de las células madre hematopoyéticas de la placenta

Hematopoietic stem cells (HSCs) have the ability to self-renew and generate all cell types of the blood lineages throughout the lifetime of an individual. ...

Isolation of Early Hematopoietic Stem Cells from Murine Yolk Sac and AGM

In the mouse embryo, early hematopoiesis occurs simultaneously in multiple organs, which includes the yolk sac and aorta-gonad-mesonephros region. These regions are crucial in establishing the blood system in the embryos and leads to the eventual movement of stem cells into the fetal liver and then development of adult stem cells in the bonemarrow. Early hematopoietic stem cells can be isolated from these organs through microdissection of the embryo followed by flow cytometric sorting to obtain a more pure population. It remains unclear how these stem cell populations contribute to the fetal and adult stem cell pool.   Also, our lab investigates how early stem cells functionally differ from fetal and adult hematopoietic stem cells. Furthermore, our lab sorts different populations of hematopoietic stem cells and test their functional role in the context of a variety of genetic models. In this video, we demonstrate the micro-dissection procedure we commonly use and also show the results of a typical FACS plotfter isolating these rare populations, it is possible to perform a variety of functional assays including: colony assays and bone marrow transplants. 



This video shows how to micro-dissect the yolk sac and aorta-gonad-mesonephros region from embryos and use flow cytometry to sort hematopoietic stem cells.

El aislamiento de las primeras células madre hematopoyéticas murinas saco vitelino y AGM

In the mouse embryo, early hematopoiesis occurs simultaneously in multiple organs, which includes the yolk sac and aorta-gonad-mesonephros region. These ...

Ex Vivo Culture of Primary Human Fallopian Tube Epithelial Cells

Epithelial ovarian cancer is a leading cause of female cancer mortality in the United States. In contrast to other women-specific cancers, like breast and uterine carcinomas, where death rates have fallen in recent years, ovarian cancer cure rates have remained relatively unchanged over the past two decades 1. This is largely due to the lack of appropriate screening tools for detection of early stage disease where surgery and chemotherapy are most effective 2, 3. As a result, most patients present with advanced stage disease and diffuse abdominal involvement. This is further complicated by the fact that ovarian cancer is a heterogeneous disease with multiple histologic subtypes 4, 5. Serous ovarian carcinoma (SOC) is the most common and aggressive subtype and the form most often associated with mutations in the BRCA genes. Current experimental models in this field involve the use of cancer cell lines and mouse models to better understand the initiating genetic events and pathogenesis of disease 6, 7. Recently, the fallopian tube has emerged as a novel site for the origin of SOC, with the fallopian tube (FT) secretory epithelial cell (FTSEC) as the proposed cell of origin 8, 9. There are currently no cell lines or culture systems available to study the FT epithelium or the FTSEC. Here we describe a novel ex vivo culture system where primary human FT epithelial cells are cultured in a manner that preserves their architecture, polarity, immunophenotype, and response to physiologic and genotoxic stressors. This ex vivo model provides a useful tool for the study of SOC, allowing a better understanding of how tumors can arise from this tissue, and the mechanisms involved in tumor initiation and progression.

Ex Vivo Culture of Primary Human Fallopian Tube Epithelial Cells

The fallopian tube (FT) is emerging as an alternative site of origin for serous ovarian carcinoma (SOC). This protocol describes a novel method for the isolation and ex vivo culture of fallopian tube epithelial cells. This system recapitulates the in vivo epithelium and allows the study of SOC pathogenesis.

Ex Vivo Cultura de células humanas primarias epiteliales del tubo de Falopio

Epithelial ovarian cancer is a leading cause of female cancer mortality in the United States. In contrast to other women-specific cancers, like breast and ...

Induction and Analysis of Epithelial to Mesenchymal Transition

Epithelial to mesenchymal transition (EMT) is essential for proper morphogenesis during development. Misregulation of this process has been implicated as a key event in fibrosis and the progression of carcinomas to a metastatic state. Understanding the processes that underlie EMT is imperative for the early diagnosis and clinical control of these disease states. Reliable induction of EMT in vitro is a useful tool for drug discovery as well as to identify common gene expression signatures for diagnostic purposes. Here we demonstrate a straightforward method for the induction of EMT in a variety of cell types. Methods for the analysis of cells pre- and post-EMT induction by immunocytochemistry are also included. Additionally, we demonstrate the effectiveness of this method through antibody-based array analysis and migration/invasion assays.

A straightforward method is described for the induction of epithelial to mesenchymal transition (EMT) in a variety of cell types. Methods for the analysis of cells in EMT states by immunocytochemistry are included.

Inducción y Análisis de epitelial a mesenquimal de transición

Epithelial  to mesenchymal transition (EMT) is essential for proper morphogenesis during  development. Misregulation of this  process has been implicated ...

Ex vivo Culture of Mouse Embryonic Skin and Live-imaging of Melanoblast Migration

Melanoblasts are the neural crest derived precursors of melanocytes; the cells responsible for producing the pigment in skin and hair. Melanoblasts migrate through the epidermis of the embryo where they subsequently colonize the developing hair follicles1,2. Neural crest cell migration is extensively studied in vitro but in vivo methods are still not well developed, especially in mammalian systems. One alternative is to use ex vivo organotypic culture3-6. Culture of mouse embryonic skin requires the maintenance of an air-liquid interface (ALI) across the surface of the tissue3,6. High resolution live-imaging of mouse embryonic skin has been hampered by the lack of a good method that not only maintains this ALI but also allows the culture to be inverted and therefore compatible with short working distance objective lenses and most confocal microscopes. This article describes recent improvements to a method that uses a gas permeable membrane to overcome these problems and allow high-resolution confocal imaging of embryonic skin in ex vivo culture6. By using a melanoblast specific Cre-recombinase expressing mouse line combined with the R26YFPR reporter line we are able to fluorescently label the melanoblast population within these skin cultures. The technique allows live-imaging of melanoblasts and observation of their behavior and interactions with the tissue in which they develop. Representative results are included to demonstrate the capability to live-image 6&#160;cultures in parallel.

Ex vivo Culture of Mouse Embryonic Skin and Live-imaging of Melanoblast Migration

We describe the dissection and ex vivo culture of mouse embryonic skin. The culture system maintains an air-liquid interface across the tissue surface and allows imaging on an inverted microscope. Melanoblasts, a component of the developing skin, are fluorescently labeled allowing their behavior to be observed using confocal microscopy.

Ex vivo Cultura de embriones de ratón con la piel y en vivo de imágenes de melanoblasto Migración

Melanoblasts are the neural crest derived precursors of melanocytes; the cells responsible for producing the pigment in skin and hair. Melanoblasts ...

In vivo Clonal Tracking of Hematopoietic Stem and Progenitor Cells Marked by Five Fluorescent Proteins using Confocal and Multiphoton Microscopy

We developed and validated a fluorescent marking methodology for clonal tracking of hematopoietic stem and progenitor cells (HSPCs) with high spatial and temporal resolution to study in vivo hematopoiesis using the murine bone marrow transplant experimental model. Genetic combinatorial marking using lentiviral vectors encoding fluorescent proteins (FPs) enabled cell fate mapping through advanced microscopy imaging. Vectors encoding five different FPs: Cerulean, EGFP, Venus, tdTomato, and mCherry were used to concurrently transduce HSPCs, creating a diverse palette of color marked cells. Imaging using confocal/two-photon hybrid microscopy enables simultaneous high resolution assessment of uniquely marked cells and their progeny in conjunction with structural components of the tissues. Volumetric analyses over large areas reveal that spectrally coded HSPC-derived cells can be detected non-invasively in various intact tissues, including the bone marrow (BM), for extensive periods of time following transplantation. Live studies combining video-rate multiphoton and confocal time-lapse imaging in 4D demonstrate the possibility of dynamic cellular and clonal tracking in a quantitative manner.

In vivo Clonal Tracking of Hematopoietic Stem and Progenitor Cells Marked by Five Fluorescent Proteins using Confocal and Multiphoton Microscopy

Combinatorial 5 fluorescent proteins marking of hematopoietic stem and progenitor cells allows in vivo clonal tracking via confocal and two-photon microscopy, providing insights into bone marrow hematopoietic architecture during regeneration. This method allows non-invasive fate mapping of spectrally-coded HSPCs-derived cells in intact tissues for extensive periods of time following transplantation.

En Tracking Clonal vivo de madre hematopoyéticas y células progenitoras Marcado por cinco proteínas fluorescentes utilizando confocal y Microscopía Multifotónica

We developed and validated a fluorescent marking methodology for clonal tracking of hematopoietic stem and progenitor cells (HSPCs) with high spatial and ...

In Vivo 4-Dimensional Tracking of Hematopoietic Stem and Progenitor Cells in Adult Mouse Calvarial Bone Marrow

Through a delicate balance between quiescence and proliferation, self renewal and production of differentiated progeny, hematopoietic stem cells (HSCs) maintain the turnover of all mature blood cell lineages. The coordination of the complex signals leading to specific HSC fates relies upon the interaction between HSCs and the intricate bone marrow microenvironment, which is still poorly understood[1-2].
We describe how by combining a newly developed specimen holder for stable animal positioning with multi-step confocal and two-photon in vivo imaging techniques, it is possible to obtain high-resolution 3D stacks containing HSPCs and their surrounding niches and to monitor them over time through multi-point time-lapse imaging. High definition imaging allows detecting ex vivo labeled hematopoietic stem and progenitor cells (HSPCs) residing within the bone marrow. Moreover, multi-point time-lapse 3D imaging, obtained with faster acquisition settings, provides accurate information about HSPC movement and the reciprocal interactions between HSPCs and stroma cells.
Tracking of HSPCs in relation to GFP positive osteoblastic cells is shown as an exemplary application of this method. This technique can be utilized to track any appropriately labeled hematopoietic or stromal cell of interest within the mouse calvarium bone marrow space.

In Vivo 4-Dimensional Tracking of Hematopoietic Stem and Progenitor Cells in Adult Mouse Calvarial Bone Marrow

The nature of the interactions between hematopoietic stem and progenitor cells (HSPCs) and bone marrow niches is poorly understood. Custom hardware modifications and a multi-step acquisition protocol allow the use of two-photon and confocal microscopy to image ex vivo labeled HSPCs homed within bone marrow areas, tracking interactions and movement.

En Vivo Tracking 4-Dimensional de madre hematopoyéticas y células progenitoras en ratones adultos de calota de Médula Ósea

Through a delicate balance between quiescence and proliferation, self renewal and production of differentiated progeny, hematopoietic stem cells (HSCs) ...