1. Remoção do embrião e dissecção da placenta <ol><li> Para começar, os embriões devem primeiro ser isolados de vacas prenhes. </li><li> Os animais são sacrificados de acordo com os procedimentos aprovados - no nosso caso vamos utilizar uma dose letal do anestésico isoflurano </li><li> Primeiro, spray a barriga com etanol e fazer uma pequena incisão com uma tesoura. </li><li> Arrancar a pele com ambas as mãos para descobrir o abdômen e corte aberto o peritônio. </li><li> Com uma pinça, pegue o cornos uterinos e recolhê-las usando uma tesoura em cada extremidade distal. Coloque o cornos uterinos em uma placa de petri preenchida com PBS e colocar no gelo. Além disso, lembre-se de lavar várias vezes com PBS antes de isolar a placenta. Agora podemos isolar a placenta. </li><li> Com duas pinças, comece a descascar cuidadosamente o tecido endometrial em torno do embrião conceptos. Deve-se ter cuidado para não furar ou não causar danos estruturais aos embriões, pois isso irá complicar a dissecção passos subseqüentes. </li><li> Coloque o conceptos isoladas numa placa de Petri novo com PBS sobre o gelo e continuar até que todos os conceptos foram libertados do endométrio. </li><li> Transferência de um concepto para uma nova placa de Petri com PBS colocado sob o microscópio e com duas pinças de descascar a decidua longe da placenta. Remover o máximo do possível decídua como células decidua irá interferir com a suspensão de uma única célula e citometria de fluxo. Um movimento contínuo suave peeling é recomendado para alcançar os melhores resultados. </li><li> Cortar o saco vitelino longe da placenta na junção entre os dois órgãos e puxe o saco vitelino e vasos vitelínico longe da placenta. Cuidados devem ser tomados para não perturbar a placa coriônica da placenta, especialmente com embriões. </li><li> Cuidadosamente segurando a placa coriônica da placenta com um par de fórceps e do cordão umbilical com outro, puxa o cordão umbilical e embrião ligado longe da placenta. </li><li> Remover o tecido celular excesso de gigante nas bordas da placenta, a fim de minimizar a aglutinação das células durante a preparação de uma única célula de suspensão. </li><li> Recolher a placenta em um recipiente apropriado, como um tubo Falcon de 15 ml, com PBS 5% FCS e no gelo. Faça isso para todas as placentas dissecados. </li><li> Neste ponto, você pode prosseguir com a preparação de uma suspensão de uma única célula de citometria de fluxo, ensaios funcionais, tais como a cultura in vitro ou transplante, ou preparar placenta inteira para fixação do tecido e bloco congelado fixo incorporação de imuno-histoquímica eventual. </li></ol> 2. Preparação de uma única célula de suspensão de tecido placenta <ol><li> Vamos agora mostrar como gerar uma suspensão única célula da placenta para análise FACS. </li><li> Para preparar uma suspensão única célula da placenta, mecânica e dissociação enzimática é necessária. Primeiro preparar uma solução de colagenase 0,1% em PBS com 10% SFB e 1% de solução a penicilina / estreptomicina. </li><li> Adicionar um volume adequado de solução de colagenase a placentas, dependendo de quantos você tem. Um volume que é o dobro do volume de placenta e entre 2-5ml é recomendado. </li><li> Use uma agulha de 16 G montado em uma seringa de 5 ml para mecanicamente perturbar o tecido por passaging a solução de colagenase e da placenta através da agulha 3 vezes. Repita com uma agulha de 18-G. </li><li> Colocar a amostra a 37 ° C, 5% incubadora de CO 2 por 45 minutos. </li><li> Após a incubação de 45 minutos em colagenase, a passagem da célula solução através de uma agulha de 20 G, e incubar por mais 45 minutos, em 37 ° C. </li><li> Após a incubação 1,5 hr total em colagenase, a passagem da célula solução a 22-G e 25-G agulhas 3 vezes com cada agulha. </li><li> Filtrar a amostra através de um filtro 50 mícrons anexado a um novo tubo Falcon de 15 ml, lavar com PBS FCS 5% e centrifugar a 4 ° C durante 5 minutos a 300 × g. </li><li> Neste ponto, temos uma única célula de suspensão adequado para FACS análise ou ensaios funcionais. </li></ol> 3. Fixação de tecidos para as secções congeladas <ol><li> Imediatamente após o isolamento da placenta de cada embrião, eles são colocados no frio 1X PBS. Normalmente, uma placa de 96 poços funciona melhor para placentas jovens (E8.5-11.5), mas com placentas mais velhos, E12.5 e mais velhos, uma placa de 24 poços pode ser mais conveniente. </li><li> Cada placenta é transferido para um novo poço cheio de recém descongelados paraformaldahyde 4% ou PFA. Para E12.5 placentas, o tecido é movido para um novo poço com a mão, mas para o E10.5 você pode remover o PBS cuidadosamente com uma pipeta e adicione o PFA. É importante que a placenta está totalmente imersa por 2-4 horas a 4 ° C, dependendo da idade e tamanho do tecido. </li><li> Transferir o tecido em sacarose 30%, ou se os tecidos são muito pequenos e frágeis, aspirar o PFA e adicione a sacarose diretamente. Nesta fase, as placentas estará flutuando em solução. Deixe os tecidos pernoite a 4 ° C.</li><li> Após a etapa durante a noite em sacarose 30%, os tecidos devem em última instância, desceria ao fundo do poço, indicativo de criopreservação apropriado. Retire metade da solução de sacarose e substituir o volume com outubro e coloque o tecido de volta em 4 ° C por 1-2 horas. Isso facilita a penetração de outubro </li><li> Transfira o tecido para outubro 100% por 1 hora, após o que pode ser incorporado. </li></ol> 4. Incorporação do tecido fixado <ol><li> Moldes de plástico com etiqueta de identificação de tecido apropriado (exemplo molde show). </li><li> Puxe o tecido para fora da solução outubro e cortar pela metade a placenta orientando a placenta em forma de disco com o lado do cordão umbilical para baixo e, cuidadosamente, cortando com uma lâmina limpa certificando-se de mover a lâmina frente e para trás antes de liberar a pressão para garantir um mesmo corte. A placenta é cortado ao meio para alcançar os melhores prientation mais tarde visualizar os HSCs placentária. </li><li> Coloque metade placenta outra na parte inferior do molde com a borda de corte em contato com a superfície inferior do molde. Repita o procedimento com um novo molde para a outra metade. Para E10.5 placentas, ambas as metades podem ser colocados no mesmo molde usando a mesma técnica. </li><li> Quando vazar outubro no molde, pode ser difícil manter o placentas na orientação correta. Assegurar a placenta no lugar, segurando a metade do tecido com uma pinça. Lentamente, deitar solução outubro no molde e evitar a produção de todas as bolhas. Para E10.5 placentas, segure uma metade do tecido por uma pinça e descansar a metade outro tecido contra a parte externa do fórceps. Lentamente, deitar outubro solução como descrito para E12.5 placentas. </li><li> Uma vez que o molde é preenchido com outubro, rapidamente colocar o molde em gelo seco, a OCT vai virar flash branco congelamento do tecido </li><li> Coloque o molde em um pequeno saco de plástico contendo Drierite e imediatamente armazenar no freezer -80 ° C. </li></ol>

<ol>
	<li>Gekas, C., Dieterlen-Lievre, F., Orkin, S. H., Mikkola, H. K. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+placenta+is+a+niche+for+hematopoietic+stem+cells.">The placenta is a niche for hematopoietic stem cells.</a> Dev Cell. 8, 365-375 (2005).</li><li>Rhodes, K. E., Gekas, C., Wang, Y., Lux, C. T., Francis, C. S., Chan, D. N., Conway, S., Orkin, S. H., Yoder, M. C., Mikkola, H. K. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Emergence+of+Hematopoietic+Stem+Cells+Is+Initiated+in+the+Placental+Vasculature+in+the+Absence+of+Circulation.">The Emergence of Hematopoietic Stem Cells Is Initiated in the Placental Vasculature in the Absence of Circulation.</a> Cell Stem Cell. 2, 252-263 (2008).</li></ol>

Os procedimentos experimentais descritos neste protocolo irá permitir isolamento e visualização do tecido placentário e tronco hematopoiéticas e células progenitoras. Para um resumo abrangente sobre a produção de celulares espera e número de HSCs na placenta e outros órgãos hematopoiéticos fetal durante o desenvolvimento fetal nos referimos a Gekas, et al. 2005. Para localização de HSCs desenvolvimento e outras células hematopoiéticas na placenta nos referimos a Rhodes, et al. 2008.

Lista de materiais: A glicose 100mM 10mM NaN3 15 ml tubos cônicos (BD) 16-G, 18-G, 20-G, 22-G e 25-G agulhas (BD) Solução de sacarose 30% Pratos Petri 35 milímetros (BD) Paraformaldeído 4% 50 - m filtros celular (Celltrics) 5 ml seringas (BD) Fosfatase alcalina Substrato Kit I (Red Vector, Vector) Fosfatase alcalina Substrato Kit III (Vector Azul, Vector) Solução (Penicilina / Estreptomicina, P / S) de antibióticos Colagenase tipo I (Sigma) Moldes Vinyl Cryomold descartáveis ​​amostras (10mm x 10mm x 5 mm, Tissue-Tek) Citoqueratina anticorpo primário (DakoCytomation) Pinça de dissecção, aço inoxidável ou titânio, número 5 ou 55 Drierite De soro fetal bovino (FBS) Plastic Fisherbrand Microscope Slides Mailer (Fisher) 1000u/ml glicose oxidase Levamisole (Vector) Montagem de mídia, meio aquoso baseado em montagem (VectamountTM AQ) Normais soro de cavalo (Vector) Temperatura ideal de corte (OCT, Tissue-Tek) Peroxidase Substrato Kit DAB (Vector) Tampão fosfato salino (PBS) com Cálcio / Magnésio (w Ca2 + / Mg2 +) Tampão fosfato salino (PBS) sem cálcio / magnésio (w / o Ca2 + / Mg2 +) Box Deslize plástico (possui 100 slides) Tubos de plástico (PVC Nalgene 180 Autoclavável não-tóxico) Test Tube polipropileno de fundo redondo, 5 ml (12x75 mm, BD Falcon) Proteinase K 20mg/ml Solução (Amresco) Produtos Research International Corp Pap Super Pen HT Markers * Slide (2,5 mm, Fisher) Da cultura de tecidos tratados em forma de U (de fundo redondo) placas de 96 poços ou 24 poços (BD Falcon) Tween20, SigmaUltra (Sigma) Kit Amplification tiramida (Invitrogen) Vectastain ABC Fosfatase Alcalina Standard Kit (Vector) Vectastain ABC Padrão Elite Kit (Vector)

isolation and analysis of hematopoietic stem cells from the placenta

Células-tronco hematopoéticas (HSCs) têm a capacidade de se auto-renovar e gerar todos os tipos de célula das linhagens de sangue durante toda a vida de um indivíduo. Todos os HSCs surgem durante o desenvolvimento embrionário, após o qual o seu tamanho da piscina é mantido por auto-renovação divisões celulares. Identificar a origem anatômica do HSCs e os eventos críticos de desenvolvimento regular do processo de desenvolvimento HSC tem sido complicada como muitos sítios anatômicos participar durante a hematopoiese fetal. Recentemente, foi identificada a placenta como um órgão hematopoiético, onde grandes HSCs são gerados e ampliado em única nichos microambientais (Gekas, et al 2005, Rhodes, et al 2008). Consequentemente, a placenta é uma importante fonte de HSCs durante o seu surgimento e expansão inicial. Neste artigo, vamos mostrar técnicas de dissecção para o isolamento de placenta murino de E10.5 e E12.5 embriões, o que corresponde aos estágios de desenvolvimento do início do HSCs eo pico do tamanho da piscina HSC na placenta, respectivamente. Além disso, apresentamos um protocolo otimizado para dissociação enzimática e mecânica de tecido placentário em uma única célula de suspensão para uso em citometria de fluxo ou ensaios funcionais. Nós descobrimos que o uso de colagenase por uma única célula suspensão da placenta dá rendimentos suficientes de HSCs. Um fator importante que afeta o rendimento HSC da placenta é o grau de dissociação mecânica antes e duração, o tratamento enzimático. Nós também fornecemos um protocolo para a preparação de fixo congelado secções de tecido placentário para a visualização do desenvolvimento de HSCs por imuno-histoquímica em seus nichos precisa celular. Como hematopoiéticas antígenos específicos não são preservadas durante a preparação das seções incluídos em parafina, que usam rotineiramente fixo cortes congelados para localizar HSCs placentária e progenitores.

Watch this Scientific Journal Video about Isolation and Analysis of Hematopoietic Stem Cells from the Placenta at JoVE.com

Isolation and Analysis of Hematopoietic Stem Cells from the Placenta

Nós identificamos a placenta como um órgão hematopoiético importante durante o desenvolvimento. Descobrimos que as células-tronco hematopoéticas (HSCs) são gerados e se expandiu na placenta em única nichos microambientais. Aqui, descrevemos as técnicas experimentais necessárias para o isolamento e visualização de HSCs na placenta mouse.

Isolamento e Análise de Células-Tronco Hematopoéticas da 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-and-analysis-of-hematopoietic-stem-cells-from-the-placenta

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Unit 1

A Hierarchical Stem-Cell System: Blood Cell Formation

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20.3K visualizações.  University of California, Los Angeles. Nós identificamos a placenta como um órgão hematopoiético importante durante o desenvolvimento. Descobrimos que as células-tronco hematopoéticas (HSCs) são gerados e se expandiu na placenta em única nichos microambientais. Aqui, descrevemos as técnicas experimentais necessárias para o isolamento e visualização de HSCs na placenta mouse.

Vídeo: Isolation and Analysis of Hematopoietic Stem Cells from the Placenta

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.

Isolamento e Transplante de Células-Tronco Hematopoéticas (HSCs)

Biologia

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.

Derivação de Células-Tronco Hematopoéticas murino de Células-Tronco Embrionárias

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 ...

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.

Isolamento de Células-Tronco Hematopoéticas início de murino saco vitelino e AGM

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

Isolation of Retinal Stem Cells from the Mouse Eye

The adult mouse retinal stem cell (RSC) is a rare quiescent cell found within the ciliary epithelium (CE) of the mammalian eye1,2,3. The CE is made up of non-pigmented inner and pigmented outer cell layers, and the clonal RSC colonies that arise from a single pigmented cell from the CE are made up of both pigmented and non-pigmented cells which can be differentiated to form all the cell types of the neural retina and the RPE. There is some controversy about whether all the cells within the spheres all contain at least some pigment4; however the cells are still capable of forming the different cell types found within the neural retina1-3. In some species, such as amphibians and fish, their eyes are capable of regeneration after injury5, however; the mammalian eye shows no such regenerative properties. We seek to identify the stem cell in vivo and to understand the mechanisms that keep the mammalian retinal stem cells quiescent6-8, even after injury as well as using them as a potential source of cells to help repair physical or genetic models of eye injury through transplantation9-12. Here we describe how to isolate the ciliary epithelial cells from the mouse eye and grow them in culture in order to form the clonal retinal stem cell spheres. Since there are no known markers of the stem cell in vivo, these spheres are the only known way to prospectively identify the stem cell population within the ciliary epithelium of the eye.

In this video, we will demonstrate how to isolate retinal stem cells from the ciliary epithelium of the mouse eye and grow them in culture to form clonal retinal spheres. The spheres that are isolated possess the cardinal properties of stem cells: self-renewal and multipotentiality.

Isolamento de Células-Tronco da retina do olho do rato

The adult mouse retinal stem cell (RSC) is a rare quiescent cell found within the ciliary epithelium (CE) of the mammalian eye1,2,3. The CE is made up of ...

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

Erythropoiesis is a commonly used model system to study cell differentiation. During erythropoiesis, pluripotent adult human hematopoietic stem cells (HSCs) differentiate into oligopotent progenitors, committed precursors and mature red blood cells 1. This process is regulated for a large part at the level of gene expression, whereby specific transcription factors activate lineage-specific genes while concomitantly repressing genes that are specific to other cell types 2. Studies on transcription factors regulating erythropoiesis are often performed using human and murine cell lines that represent, to some extent, erythroid cells at given stages of differentiation 3-5. However transformed cell lines can only partially mimic erythroid cells and most importantly they do not allow one to comprehensibly study the dynamic changes that occur as cells progress through many stages towards their final erythroid fate. Therefore, a current challenge remains the development of a protocol to obtain relatively homogenous populations of primary HSCs and erythroid cells at various stages of differentiation in quantities that are sufficient to perform genomics and proteomics experiments.
Here we describe an ex vivo cell culture protocol to induce erythroid differentiation from human hematopoietic stem/progenitor cells that have been isolated from either cord blood, bone marrow, or adult peripheral blood mobilized with G-CSF (leukapheresis). This culture system, initially developed by the Douay laboratory 6, uses cytokines and co-culture on mesenchymal cells to mimic the bone marrow microenvironment. Using this ex vivo differentiation protocol, we observe a strong amplification of erythroid progenitors, an induction of differentiation exclusively towards the erythroid lineage and a complete maturation to the stage of enucleated red blood cells. Thus, this system provides an opportunity to study the molecular mechanism of transcriptional regulation as hematopoietic stem cells progress along the erythroid lineage. 
Studying erythropoiesis at the transcriptional level also requires the ability to over-express or knockdown specific factors in primary erythroid cells. For this purpose, we use a lentivirus-mediated gene delivery system that allows for the efficient infection of both dividing and non-dividing cells 7. Here we show that we are able to efficiently knockdown the transcription factor TAL1 in primary human erythroid cells. In addition, GFP expression demonstrates an efficiency of lentiviral infection close to 90%. Thus, our protocol provides a highly useful system for characterization of the regulatory network of transcription factors that control erythropoiesis.

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

An ex vivo protocol to generate mature human red blood cells from hematopoietic stem/progenitors is described. Additionally we describe an efficient lentiviral-delivery method to knockdown the transcription factor TAL1 in primary erythroid cells. The efficiency of lentivirus mediated gene delivery is demonstrated using GFP expressing viruses.

Lentivirus mediada Durante Knockdown Ex Vivo Eritropoese de Células-Tronco Hematopoéticas

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

Phenotypic Analysis and Isolation of Murine Hematopoietic Stem Cells and Lineage-committed Progenitors

The bone marrow is the principal site where HSCs and more mature blood cells lineage progenitors reside and differentiate in an adult organism. HSCs constitute a minute cell population of pluripotent cells capable of generating all blood cell lineages for a life-time1. The molecular dissection of HSCs homeostasis in the bone marrow has important implications in hematopoiesis, oncology and regenerative medicine. We describe the labeling protocol with fluorescent antibodies and the electronic gating procedure in flow cytometry to score hematopoietic progenitor subsets and HSCs distribution in individual mice (Fig. 1). In addition, we describe a method to extensively enrich hematopoietic progenitors as well as long-term (LT) and short term (ST) reconstituting HSCs from pooled bone marrow cell suspensions by magnetic enrichment of cells expressing c-Kit. The resulting cell preparation can be used to sort selected subsets for in vitro and in vivo functional studies (Fig. 2).
Both trabecular osteoblasts2,3 and sinusoidal endothelium4 constitute functional niches supporting HSCs in the bone marrow. Several mechanisms in the osteoblastic niche, including a subset of N-cadherin+ osteoblasts3 and interaction of the receptor tyrosine kinase Tie2 expressed in HSCs with its ligand angiopoietin-15 concur in determining HSCs quiescence. "Hibernation" in the bone marrow is crucial to protect HSCs from replication and eventual exhaustion upon excessive cycling activity6. Exogenous stimuli acting on cells of the innate immune system such as Toll-like receptor ligands7 and interferon-&alpha;6 can also induce proliferation and differentiation of HSCs into lineage committed progenitors. Recently, a population of dormant mouse HSCs within the lin- c-Kit+ Sca-1+ CD150+ CD48- CD34- population has been described8. Sorting of cells based on CD34 expression from the hematopoietic progenitors-enriched cell suspension as described here allows the isolation of both quiescent self-renewing LT-HSCs and ST-HSCs9. A similar procedure based on depletion of lineage positive cells and sorting of LT-HSC with CD48 and Flk2 antibodies has been previously described10. In the present report we provide a protocol for the phenotypic characterization and ex vivo cell cycle analysis of hematopoietic progenitors, which can be useful for monitoring hematopoiesis in different physiological and pathological conditions. Moreover, we describe a FACS sorting procedure for HSCs, which can be used to define factors and mechanisms regulating their self-renewal, expansion and differentiation in cell biology and signal transduction assays as well as for transplantation.

A method to analyse the distribution of bone marrow hematopoietic progenitors in flow cytometry as well as to efficiently isolate highly purified hematopoietic stem cells (HSCs) is described. The isolation procedure is essentially based on magnetic enrichment of c-Kit+ cells and cell sorting to purify HSCs for cellular and molecular studies.

Análise fenotípica e Isolamento de Células-Tronco Hematopoéticas Murino e Lineage comprometidos Progenitores

The bone marrow is the principal site where HSCs and more mature blood cells lineage progenitors reside and differentiate in an adult organism. HSCs ...

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.

Indução e Análise de epitelial para mesenquimal Transição

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

Retroviral Infection of Murine Embryonic Stem Cell Derived Embryoid Body Cells for Analysis of Hematopoietic Differentiation

Embryonic stem cells (ESCs) are an outstanding model for elucidating the molecular mechanisms of cellular differentiation. They are especially useful for investigating the development of early hematopoietic progenitor cells (HPCs). Gene expression in ESCs can be manipulated by several techniques that allow the role for individual molecules in development to be determined. One difficulty is that expression of specific genes often has different phenotypic effects dependent on their temporal expression. This problem can be circumvented by the generation of ESCs that inducibly express a gene of interest using technology such as the doxycycline-inducible transgene system. However, generation of these inducible cell lines is costly and time consuming. Described here is a method for disaggregating ESC-derived embryoid bodies (EBs) into single cell suspensions, retrovirally infecting the cell suspensions, and then reforming the EBs by hanging drop. Downstream differentiation is then evaluated by flow cytometry. Using this protocol, it was demonstrated that exogenous expression of a microRNA gene at the beginning of ESC differentiation blocks HPC generation. However, when expressed in EB derived cells after nascent mesoderm is produced, the microRNA gene enhances hematopoietic differentiation. This method is useful for investigating the role of genes after specific germ layer tissue is derived.

Manipulating temporal gene expression in differentiating embryonic stem cells (ESCs) can be achieved using inducible gene systems. However, generation of these cell lines is costly and time consuming. This protocol achieves rapid expression of a transgene in differentiating ES-derived cells and subsequent analysis of downstream hematopoietic differentiation.

Retroviral Infecção murina Embryonic Stem Cell Derived Cells embrioides corpo de Análise da diferenciação hematopoética

Embryonic stem cells (ESCs) are an outstanding model for elucidating the molecular mechanisms of cellular differentiation. They are especially useful for ...

Identification of Key Factors Regulating Self-renewal and Differentiation in EML Hematopoietic Precursor Cells by RNA-sequencing Analysis

Hematopoietic stem cells (HSCs) are used clinically for transplantation treatment to rebuild a patient&#39;s hematopoietic system in many diseases such as leukemia and lymphoma. Elucidating the mechanisms controlling HSCs self-renewal and differentiation is important for application of HSCs for research and clinical uses. However, it is not possible to obtain large quantity of HSCs due to their inability to proliferate in vitro. To overcome this hurdle, we used a mouse bone marrow derived cell line, the EML (Erythroid, Myeloid, and Lymphocytic) cell line, as a model system for this study.
RNA-sequencing (RNA-Seq) has been increasingly used to replace microarray for gene expression studies. We report here a detailed method of using RNA-Seq technology to investigate the potential key factors in regulation of EML cell self-renewal and differentiation. The protocol provided in this paper is divided into three parts. The first part explains how to culture EML cells and separate Lin-CD34+ and Lin-CD34- cells. The second part of the protocol offers detailed procedures for total RNA preparation and the subsequent library construction for high-throughput sequencing. The last part describes the method for RNA-Seq data analysis and explains how to use the data to identify differentially expressed transcription factors between Lin-CD34+ and Lin-CD34- cells. The most significantly differentially expressed transcription factors were identified to be the potential key regulators controlling EML cell self-renewal and differentiation. In the discussion section of this paper, we highlight the key steps for successful performance of this experiment.
In summary, this paper offers a method of using RNA-Seq technology to identify potential regulators of self-renewal and differentiation in EML cells. The key factors identified are subjected to downstream functional analysis in vitro and in vivo.

RNA-sequencing and bioinformatics analyses were used to identify significantly and differentially expressed transcription factors in Lin-CD34+ and Lin-CD34- subpopulations of mouse EMLcells. These transcription factors might play important roles in determining the switch between self-renewing Lin-CD34+ and partially differentiated Lin-CD34- cells.

Identificação dos fatores chave que regula a auto-renovação e diferenciação em células precursoras hematopoéticas EML por Análise RNA-seqüenciamento

Hematopoietic stem cells (HSCs) are used clinically for transplantation treatment to rebuild a patient&#39;s hematopoietic system in many diseases such as ...

Isolation, Characterization, and Differentiation of Cardiac Stem Cells from the Adult Mouse Heart

Myocardial infarction (MI) is a leading cause of morbidity and mortality around the world. A major goal of regenerative medicine is to replenish the dead myocardium after MI. Although several strategies have been used to regenerate myocardium, stem cell therapy remains a major approach to replenish the dead myocardium of an MI heart. Accumulating evidence suggests the presence of resident cardiac stem cells (CSCs) in the adult heart and their endocrine and/or paracrine effects on cardiac regeneration. However, CSC isolation and their characterization and differentiation toward myocardial cells, especially cardiomyocytes, remains a technical challenge. In the present study, we provided a simple method for the isolation, characterization, and differentiation of CSCs from the adult mouse heart. Here, we describe a density gradient method for the isolation of CSCs, where the heart is digested by a 0.2% collagenase II solution. To characterize the isolated CSCs, we evaluated the expression of CSCs/cardiac markers Sca-1, NKX2-5, and GATA4, and pluripotency/stemness markers OCT4, SOX2, and Nanog. We also determined the proliferation potential of isolated CSCs by culturing them in a Petri dish and assessing the expression of the proliferation marker Ki-67. For evaluating the differentiation potential of CSCs, we selected seven- to ten-days cultured CSCs. We transferred them to a new plate with a cardiomyocyte differentiation medium. They are incubated in a cell culture incubator for 12 days, while the differentiation medium is changed every three days. The differentiated CSCs express cardiomyocyte-specific markers: actinin and troponin I. Thus, CSCs isolated with this protocol have stemness and cardiac markers, and they have a potential for proliferation and differentiation toward cardiomyocyte lineage.

The overall goal of this article is to standardize the protocol for the isolation, characterization, and differentiation of cardiac stem cells (CSCs) from the adult mouse heart. Here, we describe a density gradient centrifugation method to isolate murine CSCs and elaborated methods for CSC culture, proliferation, and differentiation into cardiomyocytes.

Isolamento, caracterização e diferenciação de células-tronco cardíacas do coração de rato adulto

Myocardial infarction (MI) is a leading cause of morbidity and mortality around the world. A major goal of regenerative medicine is to replenish the dead ...