Samantha Khoury e Pamela Ajuyah são suportados pelo Prêmio de Pós-Graduação da Austrália. Gostaríamos também de agradecer o Cancer Research Rede Translational, Lowy Cancer Research Centre, da Universidade de Nova Gales do Sul e da Unidade de Pesquisa do Câncer do Norte Translational pelo apoio adicional de Samantha Khoury.

Nota: as amostras de soro humano de pacientes saudáveis ​​ou pacientes com câncer foram obtidos com o consentimento informado no âmbito de protocolos éticos humanos aprovados do Royal Prince Alfred Hospital Sydney (número protocolo X10-0016 e HREC/10/RPAH/24) e da Universidade de Tecnologia, Sydney. As amostras de soro foram coletadas de pacientes antes da cirurgia de vários hospitais Sydney e colocados em armazenamento a -80 ° C. 1. Pequeno Isolamento de ARN a partir de Soro O RNA total foi preparado a partir de soro humano, utilizando uma versão modificada do protocolo LS Tri-Reagent RT. <ol><li> Descongelar amostra de soro congelado em gelo e, em seguida, transferir 400 ul do soro descongeladas recentemente para um tubo de microcentrífuga rotulado. </li><li> Diluir o soro com 100 uL de RNase livre H2O e adicionar proteinase K numa concentração de 1 mg / ml. </li><li> Incubar a 37 ° C durante 20 min para permitir a digestão de proteínas por proteinase K. </li><li> To assegurar a solubilização completa, adicionar 1,5 vezes o seu volume de Tri-Reagent RT LS e 100 uL de 4-bromoanisole. </li><li> Resumidamente inverter o homogeneizado, efectuar trabalho repetitivo de 5 seg e transferir para um tubo de 2 mL pesado Phase Lock rotulado. </li><li> Girar o homogeneizado a 12.000 x g durante 20 min a 4 ° C. </li><li> Decantar cuidadosamente, pelo menos, 1 ml da solução aquosa resultante para um tubo de ADN LoBind fresco. A interfase orgânico e deve ser preso debaixo do gel branco do tubo Phase Lock. </li><li> Adicionar 5,0 mL de glicogénio (5 mg / ml) e 500 mL de isopropanol a 100% para a solução aquosa, misturar por inversão, e incubar O / N à temperatura de -20 ° C. </li><li> Na sequência S / N de incubação, centrifuga a amostra durante 20 min a 12.000 x g numa centrífuga a 4 ° C. </li><li> Descartar o sobrenadante transparente e realizar uma rotação de &quot;flash&quot; durante 2 min a 16.000 x g numa centrífuga a 4 ° C. </li><li> Retire cuidadosamente o sol clarouição em torno do sedimento utilizando uma pipeta. </li><li> Lava-se a pelete com 1 ml de etanol a 70% e centrifuga-se a 10000 × g durante 10 min. Decantar a solução de lavagem e repita o passo de lavagem. </li></ol> 2. ARN ressuspensão em Solução <ol><li> Ressuspender o sedimento em 10 ml de RNase livre H2O, garantindo a pelete estar completamente dissolvido. Para assegurar que o RNA está completamente solubilizado, a amostra pode ser aquecida a 55 ° C durante 5 min. Durante este tempo, a mistura da amostra com pipetagem repetida. Para um rendimento total de ARN mais elevado, reunir duas preparações de RNA a partir do mesmo paciente. </li><li> Quantificar o ARN ressuspendido utilizando um espectrofotómetro de UV-Vis e avaliar a qualidade do RNA utilizando um 2100 Bioanalyzer. Armazenar as amostras de ARN reunidas a -80 ° C para utilização em aplicações a jusante. </li></ol>

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S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Detection+and+characterization+of+placental+microRNAs+in+maternal+plasma.">Detection and characterization of placental microRNAs in maternal plasma.</a> Clin. Chem. 54, 482-490 (2008).</li><li>Lodes, M. 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Não há nada a divulgar.

A população de microRNAs constitui cerca de 0,4-0,5% do ARN total encontrada no soro. Além disso, há também um alto teor de proteína encontrada em soro humano. Para melhorar o RNA e reduzir a proteína e fenol contamina modificámos a abordagem tradicional Chomczynski 9 com a adição de várias etapas. O RNA total foi isolado a partir de soro, usando o padrão de Tri-Reagent RT-LS (Centro de Investigação Molecular), no entanto, quando executados no nosso laboratório, est...

Nos últimos anos, tem havido um esforço crescente para descobrir novos biomarcadores para a detecção precoce de doenças humanas. Muita atenção tem sido focada no uso de pequenos RNAs como microRNAs 2 (miRNAs ou RIM) como potenciais marcadores. Estes pequenos RNAs são encontradas nos fluidos corporais, tais como soro e estudos têm demonstrado que são resistentes à degradação e são estáveis ​​ao longo de um intervalo de variação das condições ambientais 3. Dadas estas características miRNAs, soro ou circulantes são o biomarcador ideal 4, 5. Atualmente, existem duas abordagens principais para o isolamento de RNA pequeno a partir de fluidos biológicos. A primeira abordagem utiliza tecnologia baseada em coluna para ligar e eluir os pequenos RNAs 6, enquanto a segunda abordagem utiliza o protocolo de longa data com fenol e guanidina tiocianato reagentes 7. Nós desenvolvemos um protocolo livre de coluna simples, eficaz para isolar pequenos RNAs de soro humano. O ARN isolado é imediatamentediatamente utilizável em aplicações a jusante, incluindo arranjos de oligonucleotídeos de DNA e RNA seqüenciamento. Este protocolo foi desenvolvido porque fomos confrontados com vários problemas ao usar métodos baseados em fenol para isolar RNA do soro. A abordagem tradicional Chomczynski é freqüentemente usado na maioria dos laboratórios com uma gama de reagentes disponíveis da maioria dos fornecedores comerciais. No entanto, considerando a sua utilização generalizada, directrizes rigorosas não foram desenvolvidos para produzir consistentemente RNA de alta qualidade a partir de fluidos corporais, em particular sangue ou soro. Os problemas comuns associados com o isolamento de RNA a partir do soro incluem rendimentos baixos de RNA e contaminação com os reagentes utilizados durante o isolamento, em particular fenol. Nossa abordagem elimina esses contaminantes fenol para fornecer RNA de alta qualidade para a análise a jusante, como PCR quantitativo (qPCR) e RNA seqüenciamento. Nós testamos ainda este RNA em matrizes de miRNA.

<table border="0" cellpadding="0" cellspacing="0" style="width:852px;" width="851">
	<colgroup>
		<col />
		<col />
		<col />
		<col />
	</colgroup>
	<tbody>
		<tr height="22">
			<td height="22" style="height:22px;width:259px;">Name of the Material/Equipment&#160;</td>
			<td style="width:223px;">Company&#160;</td>
			<td style="width:123px;">Catalog Number&#160;</td>
			<td style="width:248px;">Comments/ Description (optional)&#160;</td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:259px;">Tri-Reagent RT LS</td>
			<td style="width:223px;">Molecular Research Centre, USA</td>
			<td style="width:123px;">TR 118</td>
			<td style="width:248px;">-</td>
		</tr>
		<tr height="26">
			<td height="26" style="height:26px;width:259px;">RNase free H20</td>
			<td style="width:223px;">GIBCO Invitrogen</td>
			<td style="width:123px;">10977-023</td>
			<td style="width:248px;">-</td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:259px;">Proteinase K&#160;</td>
			<td style="width:223px;">Finnzymes, Finland</td>
			<td style="width:123px;">EO0491</td>
			<td style="width:248px;">-</td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:259px;">Heavy Phaselock Tube</td>
			<td style="width:223px;">5PRIME</td>
			<td>2302830</td>
			<td style="width:248px;">2ml capacity</td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:259px;">DNA Lobind tube</td>
			<td style="width:223px;">Eppendorf</td>
			<td style="width:123px;">0030 108.078</td>
			<td style="width:248px;">1.5ml capacity</td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:259px;">Glycogen&#160;</td>
			<td style="width:223px;">Invitrogen, USA</td>
			<td style="width:123px;">10814-010</td>
			<td style="width:248px;">5mg/ml</td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:259px;">RNA grade Isopropanol&#160;</td>
			<td style="width:223px;">Sigma Aldrich, USA</td>
			<td style="width:123px;">I9516</td>
			<td style="width:248px;">100%</td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:259px;">Refrigerated Centrifuge</td>
			<td style="width:223px;">John Morris</td>
			<td style="width:123px;">-</td>
			<td style="width:248px;">-</td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:259px;">Nanodrop UV-Vis spectrophotometer</td>
			<td style="width:223px;">Thermo Fisher Scientific, USA</td>
			<td style="width:123px;">-</td>
			<td style="width:248px;">-</td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:259px;">RNA grade Ethanol</td>
			<td style="width:223px;">Sigma Aldrich, USA</td>
			<td style="width:123px;">E7023</td>
			<td style="width:248px;">70%</td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:259px;">Agilent 2100 Bioanalyser</td>
			<td style="width:223px;">Agilent, USA</td>
			<td style="width:123px;">-</td>
			<td style="width:248px;">-</td>
		</tr>
	</tbody>
</table>

isolation of small noncoding rnas from human serum

A análise do ARN e a sua expressão é uma característica comum em muitos laboratórios. De importância é o surgimento de pequenos RNAs como microRNAs, que são encontradas em células de mamíferos. Estes pequenos RNAs são genes reguladores potentes que controlam as vias vitais como crescimento, desenvolvimento e morte e muito interesse tem sido direcionada para a sua expressão em fluidos corporais. Isto é devido à sua desregulação em doenças humanas como câncer e sua potencial aplicação como marcadores biológicos. No entanto, a análise da expressão de miARN no soro pode ser problemático. Na maioria dos casos, a quantidade de soro é limitante e soro contém baixas quantidades de ARN total, da qual os pequenos RNAs constituem apenas 0,4-0,5% 1. Assim, o isolamento de quantidades suficientes de ARN de qualidade a partir de soro é um grande desafio para os investigadores hoje. Neste documento técnico, demonstramos um método que utiliza apenas 400 mL de soro humano para obter RNA suficiente tanto para matrizes de DNA ou análise de qPCR. A umdvantages deste método são sua simplicidade e capacidade para produzir RNA de alta qualidade. Ele não requer colunas especializadas para purificação de pequenos RNAs e utiliza reagentes gerais e hardware encontrados em laboratórios comuns. O nosso método utiliza uma fase de bloqueio do gel para eliminar a contaminação com fenol e, ao mesmo tempo obtendo-se o RNA de alta qualidade. Apresentamos também um passo adicional para remover mais contaminantes durante a fase de isolamento. Este protocolo é muito eficaz no isolamento de rendimentos de ARN total de até 100 ng / mL de soro, mas também podem ser adaptadas para outros tecidos biológicos.

A Figura 1 representa um espectro típico de UV / Vis de RNA isolado a partir do soro. A partir deste perfil, observamos contaminação de proteína a 280 nm com fenol e contaminantes orgânicos, tanto a 270 nm e 230 nm, respectivamente. Resíduo de tiocianato de guanidina foi também observado a 260 nm. Para reduzir os contaminantes, uma série de passos de optimização foram feitas com o processo RT-LS Tri-Reagent padrão. Nós adicionados 5 mg / mL de glicogénio para aumentar tanto o rendimento tot...

Watch this Scientific Journal Video about Isolation of Small Noncoding RNAs from Human Serum at JoVE.com

Isolation of Small Noncoding RNAs from Human Serum

Este protocolo descreve um método para extrair pequenos RNAs de soro humano. Temos utilizado este método para isolar microRNAs de soro câncer para uso em matrizes de DNA e também singleplex PCR quantitativo. O protocolo utiliza fenol e tiocianato de guanidina reagentes com modificações para produzir RNA de alta qualidade.

Isolamento de ARN a partir de pequenas não-codificante de Soro Humano

The analysis of RNA and its expression is a common feature in many laboratories. Of significance is the emergence of small RNAs like microRNAs, which are ...

isolation-of-small-noncoding-rnas-from-human-serum

Research

JoVE Journal

Biology

18.0K visualizações.  University of Technology, Sydney.  Este protocolo descreve um método para extrair pequenos RNAs de soro humano. Temos utilizado este método para isolar microRNAs de soro câncer para uso em matrizes de DNA e também singleplex PCR quantitativo. O protocolo utiliza fenol e tiocianato de guanidina reagentes com modificações para produzir RNA de alta qualidade. 

Vídeo: Isolation of Small Noncoding RNAs from Human Serum

Neuronal Nuclei Isolation from Human Postmortem Brain Tissue

Neurons in the human brain become postmitotic largely during prenatal development, and thus maintain their nuclei throughout the full lifespan. However, little is known about changes in neuronal chromatin and nuclear organization during the course of development and aging, or in chronic neuropsychiatric disease. However, to date most chromatin and DNA based assays (other than FISH) lack single cell resolution. To this end, the considerable cellular heterogeneity of brain tissue poses a significant limitation, because typically various subpopulations of neurons are intermingled with different types of glia and other non-neuronal cells. One possible solution would be to grow cell-type specific cultures, but most CNS cells, including neurons, are ex vivo sustainable, at best, for only a few weeks and thus would provide an incomplete model for epigenetic mechanisms potentially operating across the full lifespan.  Here, we provide a protocol to extract and purify nuclei from frozen (never fixed) human postmortem brain. The method involves extraction of nuclei in hypotonic lysis buffer, followed by ultracentrifugation and immunotagging with anti-NeuN antibody. Labeled neuronal nuclei are then collected separately using fluorescence-activated sorting. This method should be applicable to any brain region in a wide range of species and suitable for chromatin immunoprecipitation studies with site- and modification-specific anti-histone antibodies, and for DNA methylation and other assays. 

The cellular heterogeneity of brain tissue poses a significant limitation for the study of epigenetic markings in chromatin because most assays lack single cell resolution. Neurons typically are intermingled with glia and other non-neuronal cells. We provide a protocol to extract and collect neuronal nuclei from human brain.

Isolamento Núcleos neuronais de Tecidos Humanos Postmortem Cérebro

Neurons in the human brain become postmitotic largely during prenatal development, and thus maintain their nuclei throughout the full lifespan. However, ...

Biologia

Isolation of Stem Cells from Human Pancreatic Cancer Xenografts

Cancer stem cells (CSCs) have been identified in a growing number of malignancies and are functionally defined by their ability to undergo self-renewal and produce differentiated progeny1. These properties allow CSCs to recapitulate the original tumor when injected into immunocompromised mice. CSCs within an epithelial malignancy were first described in breast cancer and found to display specific cell surface antigen expression (CD44+CD24low/-)2. Since then, CSCs have been identified in an increasing number of other human malignancies using CD44 and CD24 as well as a number of other surface antigens. Physiologic properties, including aldehyde dehydrogenase (ALDH) activity, have also been used to isolate CSCs from malignant tissues3-5.
Recently, we and others identified CSCs from pancreatic adenocarcinoma based on
ALDH activity and the expression of the cell surface antigens CD44 and CD24, and CD1336-8. These highly tumorigenic populations may or may not be overlapping and display other functions. We found that ALDH+ and CD44+CD24+ pancreatic CSCs are similarly tumorigenic, but ALDH+ cells are relatively more invasive8. In this protocol we describe a method to isolate viable pancreatic CSCs from low-passage human
xenografts9. Xenografted tumors are harvested from mice and made into a single-cell suspension. Tissue debris and dead cells are separated from live cells and then stained using antibodies against CD44 and CD24 and using the ALDEFLUOR reagent,
a fluorescent substrate of ALDH10. CSCs are then isolated by fluorescence activated cell sorting. Isolated CSCs can then be used for analytical or functional assays requiring viable cells.

Cancer stem cells (CSCs) have been identified in a number of malignancies. In this protocol we describe a flow cytometric method utilizing aldehyde dehydrogenase activity and CD44 and CD24 expression to isolate CSCs from human pancreatic adenocarcinoma xenografts. These viable cells can then be used in functional and analytical studies.

Isolamento de células-tronco de xenoenxertos Humano do Câncer de pâncreas

Cancer stem cells (CSCs) have been identified in a growing number of malignancies and are functionally defined by their ability to undergo self-renewal ...

Isolation and Culture of Adult Epithelial Stem Cells from Human Skin

The homeostasis of all self-renewing tissues is dependent on adult stem cells. As undifferentiated stem cells undergo asymmetric divisions, they generate daughter cells that retain the stem cell phenotype and transit-amplifying cells (TA cells) that migrate from the stem cell niche, undergo rapid proliferation and terminally differentiate to repopulate the tissue.
Epithelial stem cells have been identified in the epidermis, hair follicle, and intestine as cells with a high in vitro proliferative potential and as slow-cycling label-retaining cells in vivo 1-3. Adult, tissue-specific stem cells are responsible for the regeneration of the tissues in which they reside during normal physiologic turnover as well as during times of stress 4-5. Moreover, stem cells are generally considered to be multi-potent, possessing the capacity to give rise to multiple cell types within the tissue 6. For example, rodent hair follicle stem cells can generate epidermis, sebaceous glands, and hair follicles 7-9. We have shown that stem cells from the human hair follicle bulge region exhibit multi-potentiality 10.
Stem cells have become a valuable tool in biomedical research, due to their utility as an in vitro system for studying developmental biology, differentiation, tumorigenesis and for their possible therapeutic utility. It is likely that adult epithelial stem cells will be useful in the treatment of diseases such as ectodermal dysplasias, monilethrix, Netherton syndrome, Menkes disease, hereditary epidermolysis bullosa and alopecias 11-13. Additionally, other skin problems such as burn wounds, chronic wounds and ulcers will benefit from stem cell related therapies 14,15. Given the potential for reprogramming of adult cells into a pluripotent state (iPS cells)16,17, the readily accessible and expandable adult stem cells in human skin may provide a valuable source of cells for induction and downstream therapy for a wide range of disease including diabetes and Parkinson's disease.

A rapid, robust way of isolating viable adult epithelial stem cells from human skin is described. The method utilizes enzymatic digestion of skin collagen matrix , followed by plucking of hair follicles and isolation of single cell suspensions or tissue fragments for cell culture.

Isolamento e Cultura de Células-Tronco Adultas epitelial da pele humana

The homeostasis of all self-renewing tissues is dependent on adult stem cells. As undifferentiated stem cells undergo asymmetric divisions, they generate ...

Efficient Derivation of Human Cardiac Precursors and Cardiomyocytes from Pluripotent Human Embryonic Stem Cells with Small Molecule Induction

To date, the lack of a suitable human cardiac cell source has been the major setback in regenerating the human myocardium, either by cell-based transplantation or by cardiac tissue engineering1-3. Cardiomyocytes become terminally-differentiated soon after birth and lose their ability to proliferate. There is no evidence that stem/progenitor cells derived from other sources, such as the bone marrow or the cord blood, are able to give rise to the contractile heart muscle cells following transplantation into the heart1-3. The need to regenerate or repair the damaged heart muscle has not been met by adult stem cell therapy, either endogenous or via cell delivery1-3. The genetically stable human embryonic stem cells (hESCs) have unlimited expansion ability and unrestricted plasticity, proffering a pluripotent reservoir for in vitro derivation of large supplies of human somatic cells that are restricted to the lineage in need of repair and regeneration4,5. Due to the prevalence of cardiovascular disease worldwide and acute shortage of donor organs, there is intense interest in developing hESC-based therapies as an alternative approach. However, how to channel the wide differentiation potential of pluripotent hESCs efficiently and predictably to a desired phenotype has been a major challenge for both developmental study and clinical translation. Conventional approaches rely on multi-lineage inclination of pluripotent cells through spontaneous germ layer differentiation, resulting in inefficient and uncontrollable lineage-commitment that is often followed by phenotypic heterogeneity and instability, hence, a high risk of tumorigenicity6-8 (see a schematic in Fig. 1A). In addition, undefined foreign/animal biological supplements and/or feeders that have typically been used for the isolation, expansion, and differentiation of hESCs may make direct use of such cell-specialized grafts in patients problematic9-11. To overcome these obstacles, we have resolved the elements of a defined culture system necessary and sufficient for sustaining the epiblast pluripotence of hESCs, serving as a platform for de novo derivation of clinically-suitable hESCs and effectively directing such hESCs uniformly towards clinically-relevant lineages by small molecules12 (see a schematic in Fig. 1B). After screening a variety of small molecules and growth factors, we found that such defined conditions rendered nicotinamide (NAM) sufficient to induce the specification of cardiomesoderm direct from pluripotent hESCs that further progressed to cardioblasts that generated human beating cardiomyocytes with high efficiency (Fig. 2). We defined conditions for induction of cardioblasts direct from pluripotent hESCs without an intervening multi-lineage embryoid body stage, enabling well-controlled efficient derivation of a large supply of human cardiac cells across the spectrum of developmental stages for cell-based therapeutics.

We have established a protocol for induction of cardioblasts direct from pluripotent human embryonic stem cells maintained under defined conditions with small molecules, which enables derivation of a large supply of human cardiac progenitors and functional cardiomyocytes for cardiovascular repair.

Derivação eficiente dos recursos humanos Precursores cardíaca e Cardiomyocytes pluripotentes a partir de células estaminais embrionárias humanas com a indução de moléculas pequenas

To date, the lack of a suitable human cardiac cell source has been the major setback in regenerating the human myocardium, either by cell-based ...

Manual Isolation of Adipose-derived Stem Cells from Human Lipoaspirates

In 2001, researchers at the University of California, Los Angeles, described the isolation of a new population of adult stem cells from liposuctioned adipose tissue that they initially termed Processed Lipoaspirate Cells or PLA cells. Since then, these stem cells have been renamed as Adipose-derived Stem Cells or ASCs and have gone on to become one of the most popular adult stem cells populations in the fields of stem cell research and regenerative medicine. Thousands of articles now describe the use of ASCs in a variety of regenerative animal models, including bone regeneration, peripheral nerve repair and cardiovascular engineering. Recent articles have begun to describe the myriad of uses for ASCs in the clinic. The protocol shown in this article outlines the basic procedure for manually and enzymatically isolating ASCs from large amounts of lipoaspirates obtained from cosmetic procedures. This protocol can easily be scaled up or down to accommodate the volume of lipoaspirate and can be adapted to isolate ASCs from fat tissue obtained through abdominoplasties and other similar procedures.

In 2001, researchers at UCLA described the isolation of a population of adult stem cells, termed Adipose-derived Stem Cells or ASCs, from adipose tissue. This article outlines the isolation of ASCs from lipoaspirates using a manual, enzymatic digestion protocol using collagenase.

Isolamento manual de células-tronco adiposo-derivadas de Lipoaspirates Humanos

In 2001, researchers at the University of  California, Los Angeles, described the isolation of a new population of adult  stem cells from liposuctioned ...

Isolation of Primary Myofibroblasts from Mouse and Human Colon Tissue

The myofibroblast is a stromal cell of the gastrointestinal (GI) tract that has been gaining considerable attention for its critical role in many GI functions. While several myofibroblast cell lines are commercially available to study these cells in vitro, research results from a cell line exposed to experimental cell culture conditions have inherent limitations due to the overly reductionist nature of the work. Use of primary myofibroblasts offers a great advantage in terms of confirming experimental findings identified in a cell line. Isolation of primary myofibroblasts from an animal model allows for the study of myofibroblasts under conditions that more closely mimic the disease state being studied. Isolation of primary myofibroblasts from human colon tissue provides arguably the most relevant experimental data, since the cells come directly from patients with the underlying disease. We describe a well-established technique that can be utilized to isolate primary myofibroblasts from both mouse and human colon tissue. These isolated cells have been characterized to be alpha-smooth muscle actin and vimentin-positive, and desmin-negative, consistent with subepithelial intestinal myofibroblasts. Primary myofibroblast cells can be grown in cell culture and used for experimental purposes over a limited number of passages.

The myofibroblast is an influential stromal cell of the gastrointestinal tract that regulates important physiologic processes in both normal and disease states. We describe a technique that allows for the isolation of primary myofibroblasts from both mouse and human colon tissue, which can be utilized for in vitro experimentation.

Isolamento de primárias Miofibroblastos de Mouse e tecido do cólon humano

The myofibroblast is  a stromal cell of the gastrointestinal (GI) tract that has been gaining  considerable attention for its critical role in many GI ...

Isolation of Myofibroblasts from Mouse and Human Esophagus

Murine and human esophageal myofibroblasts are generated via enzymatic digestion. Neonate (8-12 day old) murine esophagus is harvested, minced, washed, and subjected to enzymatic digestion with collagenase and dispase for 25 min. Human esophageal resection specimens are stripped of muscularis propria and adventitia and the remaining mucosa is minced, and subjected to enzymatic digestion with collagenase and dispase for up to 6 hr. Cultured cells express &#945;-SMA and vimentin and express desmin weakly or not at all. Culture conditions are not conducive to growth of epithelial, hematopoietic, or endothelial cells. Culture purity is further confirmed by flow cytometric evaluation of cell surface marker expression of potential contaminating hematopoietic and endothelial cells. The described technique is straightforward and results in consistent generation of non-hematopoieitc, non-endothelial stromal cells. Limitations of this technique are inherent to the use of primary cultures in molecular biology studies, i.e., the unavoidable variability encountered among cultures established across different mice or humans. Primary cultures however are a more representative reflection of the in vivo state compared to cell lines. These methods also provide investigators the ability to isolate and culture stromal cells from different clinical and experimental conditions, allowing comparisons between groups. Characterized esophageal stromal cells can also be used in functional studies investigating epithelial-stromal interactions in esophageal disorders.

We present a protocol to generate primary cultures of murine and human esophageal stromal cells with a myofibroblast phenotype. Cultured cells have spindle shaped morphology, express &#945;-SMA and vimentin, and lack epithelial, hematopoietic and endothelial cell surface markers. Characterized stromal cells can be used in functional studies of epithelial-stromal interactions.

Isolamento de Miofibroblastos de Mouse e esôfago humano

Murine and human esophageal myofibroblasts are generated via enzymatic digestion. Neonate (8-12 day old) murine esophagus is harvested, minced, washed, ...

Isolation of Human Ventricular Cardiomyocytes from Vibratome-Cut Myocardial Slices

The isolation of ventricular cardiac myocytes from animal and human hearts is a fundamental method in cardiac research. Animal cardiomyocytes are commonly isolated by coronary perfusion with digestive enzymes. However, isolating human cardiomyocytes is challenging because human myocardial specimens usually do not allow for coronary perfusion, and alternative isolation protocols result in poor yields of viable cells. In addition, human myocardial specimens are rare and only regularly available at institutions with on-site cardiac surgery. This hampers the translation of findings from animal to human cardiomyocytes. Described here is a reliable protocol that enables efficient isolation of ventricular myocytes from human and animal myocardium. To increase the surface-to-volume ratio while minimizing cell damage, myocardial tissue slices 300 &#181;m thick are generated from myocardial specimens with a vibratome. Tissue slices are then digested with protease and collagenase. Rat myocardium was used to establish the protocol and quantify yields of viable, calcium-tolerant myocytes by flow-cytometric cell counting. Comparison with the commonly used tissue-chunk method showed significantly higher yields of rod-shaped cardiomyocytes (41.5 &#177; 11.9 vs. 7.89 &#177; 3.6%, p &#60; 0.05). The protocol was translated to failing and non-failing human myocardium, where yields were similar as in rat myocardium and, again, markedly higher than with the tissue-chunk method (45.0 &#177; 15.0 vs. 6.87 &#177; 5.23 cells/mg, p &#60; 0.05). Notably, with the protocol presented it is possible to isolate reasonable numbers of viable human cardiomyocytes (9&#8211;200 cells/mg) from minimal amounts of tissue (&#60;50 mg). Thus, the method is applicable to healthy and failing myocardium from both human and animal hearts. Furthermore, it is possible to isolate excitable and contractile myocytes from human tissue specimens stored for up to 36 h in cold cardioplegic solution, rendering the method particularly useful for laboratories at institutions without on-site cardiac surgery.

Presented is a protocol for the isolation of human and animal ventricular cardiomyocytes from vibratome-cut myocardial slices. High yields of calcium-tolerant cells (up to 200 cells/mg) can be obtained from small amounts of tissue (&#60;50 mg). The protocol is applicable to myocardium exposed to cold ischemia for up to 36 h.

Isolamento de Cardiomiócitos Ventriculares Humanos de fatias de miocárdio cortadas por vibratome

The isolation of ventricular cardiac myocytes from animal and human hearts is a fundamental method in cardiac research. Animal cardiomyocytes are commonly ...

Isolation of Human Neutrophils from Whole Blood and Buffy Coats

Neutrophils (PMNs) are the most abundant leukocytes in human circulation, ranging from 40 to 70% of total blood leukocytes. They are the first cells recruited at the site of inflammation via rapid extravasation through vessels. There, neutrophils perform an array of functions to kill invading pathogens and mediate immune signaling. Freshly purified neutrophils from human blood are the model of choice for study, as no cell line fully replicates PMN functions and biology. However, neutrophils are short-lived, terminally differentiated cells and are highly susceptible to activation in response to physical (temperature, centrifugation speed) and biological (endotoxin, chemo- and cytokines) stimuli. Therefore, it is crucial to follow a standardized, reliable, and fast method to obtain pure and non-activated cells. This protocol presents an updated protocol combining density gradient centrifugation, red blood cell (RBC) sedimentation, and RBC lysis to obtain high PMN purity and minimize cell activation. Furthermore, methods to assess neutrophil isolation quality, viability, and purity are also discussed.

This protocol details a method for the isolation of neutrophils from whole blood, buffy coats, or leukapheresis membranes, achieving good yield, high purity, and minimal cell activation. We utilize gradient purification, red blood cell (RBC) sedimentation, and RBC lysis to obtain a high-quality/purity neutrophil preparation.

Isolamento de neutrófilos humanos de whole blood e buffy coats

Neutrophils (PMNs) are the most abundant leukocytes in human circulation, ranging from 40 to 70% of total blood leukocytes. They are the first cells ...

Isolation of Epithelial Cells from Human Dental Follicle

The dental follicle (DF) was harvested during the removal of an impacted third molar by an oral maxillofacial surgeon. Epithelial cell isolation was performed on the day of DF harvest. The DF was washed three times with DPBS and then dissected with tissue scissors until the tissue had a pulpy or squishy consistency. Single-cell populations were pelleted by centrifugation and washed with keratinocyte serum-free medium. Heterogeneous cell populations were distributed in a culture dish. Keratinocyte serum-free medium was used to select the epithelial cells. The culture medium was changed daily until no floating debris or dead cells were observed. Epithelial cells appeared within 7-10 days after cell population distribution. Epithelial cells survived in serum-free medium, while &#945;-modification minimal essential medium supplemented with 10% fetal bovine serum allowed the proliferation of mesenchymal-type cells. The DF is a tissue source for the isolation of dental epithelial cells.
The purpose of this study was to establish a method for the isolation of epithelial cells from human DF. Periodontal ligament (PDL) was used for the isolation of human dental epithelial cells. Procuring epithelial cells from human PDL is not always successful due to the small tissue volume, leading to low numbers of epithelial cells. DF has a larger volume than PDL and contains more cells. DF can be a tissue source for the primary culture of human dental epithelial cells. This protocol is easier and more efficient than the isolation method using PDL. Procuring human dental epithelial cells may facilitate further studies of dental epithelial-mesenchymal interactions.

The dental follicle contains an epithelial population and mesenchymal cells. The epithelial population was selected from the heterogeneous dental follicle cell population by providing a distinct culture medium. Epithelial cells survived and formed colonies in a serum-free medium.

Isolamento de Células Epiteliais do Folículo Dental Humano

The dental follicle (DF) was harvested during the removal of an impacted third molar by an oral maxillofacial surgeon. Epithelial cell isolation was ...

Methods Article

Isolamento de ARN a partir de pequenas não-codificante de Soro Humano