Questo protocollo è stato testato e ottimizzato nel laboratorio del Dr. David Scadden. Il finanziamento è fornito dal Dana Farber Cancer Institute / Massachusetts General Hospital di Ematologia e Oncologia Clinica Fellowship Program.

<ol><li> Iniziamo l&#39;esperimento homing con l&#39;estrazione di cellule da utilizzare per l&#39;esperimento. Per questo esperimento in corso siamo interessati a scoprire se l&#39;homing di midollo osseo intero le nicchie nelle ossa lunghe degli animali beneficiari è differente per le cellule del midollo osseo viene quindi prelevato da animali WT come C57BL/6J (WT) e quelli che sono transgenici fori per il recettore Lysophosphatidic 1 (LPAR1) (KO). </li><li> Prima di iniziare l&#39;esperimento, che raccoglierà i materiali di cui abbiamo bisogno per questo esperimento. Nel nostro laboratorio tutte le dissezioni del mouse sono svolte in una cappa flusso laminare cultura dei tessuti, soprattutto se le cellule stanno per essere trapiantate in un animale destinatario, invece di essere utilizzato per l&#39;analisi ex-vivo. Si comincia mettendo un foglio blu all&#39;interno della cappa. Altri oggetti sono necessari un paio di pinze e un paio di forbici affilate che sono stati sterilizzati in autoclave, un tampone sterile monouso bisturi e alcol. Avremo bisogno modificato PBS e una sterile 6 pozzetti, un mortaio, pestello, blu 50cc superato tubo conico e un filtro 70uM usa e getta. </li><li> Iniziamo prendendo una WT e un mouse KO. </li><li> Questi topi sono eutanasia da CO 2 inalazione e poi immersi nel 70% isopropranolol per 5 secondi. Questo passaggio impedisce la contaminazione delle cellule di interesse con il mouse e la pelliccia nelle nostre mani, non ha portato ad alcun compromesso della resa di cellule o risultati sperimentali. </li><li> I topi sono poi sezionati a sua volta, usando un paio di pinze e forbici affilate. Di solito inizia con il mouse WT come una questione di routine. Un snip piccola è realizzata in pelle ventrale del mouse sovrastante l&#39;addome e la pelle è poi allungato con le mani. La pelle si stacca con facilità gli arti posteriori. Il femore e la tibia vengono poi estratte facendo attenzione a non spostare la testa del femore come questa contiene una grande quantità di midollo osseo. Gli arti superiori sono staccata dal busto dell&#39;animale semplicemente applicando una trazione a loro, mantenendo il busto immobile. Ciò elimina gli arti superiori come un pezzo. Gli omeri vengono poi estratti dalle arti superiori. </li><li> Le ossa rimosse sono posti in PBS modificato che è stato aggiunto a 6 piastre. Modificato PBS è fatta con l&#39;aggiunta di 2 ml di calore inattivato siero fetale bovino e 2 cc di EDTA 0,5 M pH8. Questa soluzione viene poi filtrata attraverso un 0,45 Nalgene uM filtro e può essere conservato a 4 ° C per almeno un mese. </li><li> E &#39;essenziale per etichettare i pozzi nella piastra in modo da essere in grado di identificare WT e ossa KO correttamente. </li><li> Le carcasse di topo sono stati rimossi e smaltiti. </li><li> Un nuovo foglio si trova nel cofano e le ossa sono puliti con un bisturi monouso. </li><li> Le ossa pulite sono posti un mouse in un momento nel mortaio. Due ml di PBS modificato viene aggiunta alla malta e le ossa sono schiacciati con un pestello. E &#39;importante primo frammento delle ossa con 10 movimenti avanti e indietro del pestello e poi polverizzare con movimenti rotatori circolari. Di solito lo faccio 50 in senso orario, poi 50 movimenti in senso antiorario e così via fino a quando il materiale lasciato nel mortaio è di colore bianco e la PBS modificato aggiunti al materiale rimane bianca o trasparente. </li><li> Dopo ogni serie di 50 movimenti circolari frantumazione, abbiamo trasferire il liquido dalla malta per il 70 uM filtro collocato su un tubo da 50 ml. Non dimenticate di aggiungere 2 ml di PBS alla malta dopo ogni trasferimento il filtro. Non si vuole cercare di polverizzare ossa secche o lasciarli a secco per un certo periodo di tempo come questo porterà ad apoptosi delle cellule. </li><li> Una volta che il materiale nel mortaio diventa bianco, il materiale nel filtro viene trasferita la malta e la frantumazione è di nuovo eseguita. Questo assicura che le cellule del filtro non sono sprecati. Di solito ci vogliono uno o due serie di movimenti rotatori circolari per rendere di nuovo il materiale in bianco malta di colore in quel momento l&#39;estrazione delle cellule è completa. </li><li> La soluzione nel tubo conico è ora centrifugato (ricordatevi di conservare le cellule dal WT e KO mouse separato. Quindi si avranno due tubi diversi (uno con celle di WT, l&#39;altro con cellule KO). Centrifugare a 1200 rpm per 10 minuti. </li><li> Aspirare il sopranatante con pipette aspirazione separate per ogni provetta. Aggiungere 2 cc di tampone di lisi ACK ad ogni pellet. Questo tampone di lisi devono essere sterili. Incubare in ghiaccio per 5 minuti. </li><li> Aggiungere 8 cc di PBS modificato ad ogni provetta. Prendete 10 ul da ciascuna provetta e pipettare in due pozzetti separati in una piastra da 96 pozzetti. Collocare le provette nella centrifuga e spin loro a 1200 rpm per 10 minuti. </li><li> Mentre i tubi girano, aggiungere 30 ul di tryphan colorante blu e 60 ul di PBS modificato in ciascun pozzetto della piastra 96 ​​pozzetti che porta le cellule di interesse. </li><li> Aggiungere 10 ul di questa miscela (si prega di mescolare bene pipettando su e giù) ad un emocitometro e contare le cellule nelle quattro piazze esterne. </li><li> La conta delle cellule in ogni campione per ml è il numero di cellule contate così diviso per 4 e multiplied di 100 000. </li><li> Una volta che la centrifugazione, rimuovere i tubi dalla centrifuga e risospendere le cellule in PBS senza calcio, magnesio o glutammina L ad una concentrazione di 20 milioni di cellule per ml. Molto probabilmente non avrete circa 5 ml di volume per il WT e 5 ml di volume per l&#39;animale KO. Da questo punto in poi useremo PBS, non modificato PBS per il protocollo. </li><li> Per ogni tubo aggiungere Dii, un colorante colorazione delle cellule, per ottenere una concentrazione finale di 5um. Agitare immediatamente al Vortex per 10 secondi. Incubare a 37 gradi per 10 minuti ed evitare l&#39;esposizione alla luce. </li><li> Riempire i tubi con PBS e girare per 10 minuti a 1200 giri al minuto. </li><li> Dopo la centrifugazione, aspirare il supernatante e risospendere le cellule in PBS a 40 milioni di cellule per ml. </li><li> Carico 500 ul in siringhe da 1 cc con un ago 27G (5 siringhe per il mouse WT e 5 siringhe per i topi KO). Può essere prudente per preparare 6 siringhe per ogni coorte. Avendo in più si può aiutare le iniezioni vena della coda, che ci accingiamo a fare dopo può essere difficile. </li><li> Coprire le siringhe con un foglio in modo da mantenere il DII di disintegrazione. </li><li> Iniettare 500 ul della miscela in ogni cellula animale destinatario; (5 per ogni coorte). </li><li> Questi animali devono essere irradiati con 9 Gy di irradiazione 4-24 ore prima dell&#39;iniezione. </li><li> 48 ore dopo l&#39;iniezione, midollo osseo raccolta dal arti posteriori di ogni animale destinatario. </li><li> Processo come descritto sopra per i donatori. Risospendere le cellule di ogni animale in 1 cc di PBS. Ottenere una conta delle cellule utilizzando un emocitometro. </li><li> Leggere sul citometro a flusso LSR II da BD o un atto equivalente. Il risultato può essere espresso come numero assoluto o percentuale di cellule nel midollo osseo analizzato quali sono DII positivi. </li></ol>

<ol>
	<li>Adams, G. B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stem+cell+engraftment+at+the+endosteal+niche+is+specified+by+the+calcium-sensing+receptor.">Stem cell engraftment at the endosteal niche is specified by the calcium-sensing receptor.</a> Nature. 439 (7076), 599-603 (2006).</li><li>Broxmeyer, H. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chemokines+in+hematopoiesis.">Chemokines in hematopoiesis.</a> Curr Opin Hematol. 15 (1), 49-58 (2008).</li></ol>

Homing è il processo attraverso il quale le cellule del midollo osseo comprese le cellule staminali, le cellule staminali e differenziate, la loro strada nel midollo osseo dopo essere stata iniettata nel flusso del sangue o del midollo osseo di topi cavità. Come è evidente dalla definizione, uno scienziato può scegliere di studiare l&#39;homing delle cellule staminali ematopoietiche, cellule progenitrici o cellule differenziate da immunofenotipizzazione identificato e isolato dalla separazione delle cellule. Di soli...

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<td>Mediatech, Inc</td>
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homing of hematopoietic cells to the bone marrow

Homing è il fenomeno per cui trapiantato cellule ematopoietiche sono in grado di viaggiare da e per innestare o stabilire la residenza nel midollo osseo. Chemomkines vari recettori sono coinvolti nella homing delle cellule staminali ematopoietiche. [1, 2] Questo documento descrive il protocollo classico homing utilizzati negli studi di cellule staminali ematopoietiche. In generale si tratta di isolare la popolazione di cellule il cui homing ha bisogno di essere indagato, colorazione questa popolazione con un colorante di interesse e iniettando queste cellule nel sangue di un animale destinatario. L&#39;animale destinatario è poi sacrificata a un pre-determinato tempo dopo l&#39;iniezione e il midollo osseo per valutare la percentuale o il numero assoluto di cellule che sono positivi per la tintura di interesse. In uno degli schemi più comuni sperimentale, l&#39;efficienza di homing delle cellule ematopoietiche da due animali geneticamente distinte (un tipo di animale selvatico e il corrispondente knock-out) è confrontato. Questo articolo descrive il protocollo di homing delle cellule ematopoietiche nel quadro di come esperimento.

Watch this Scientific Journal Video about Homing of Hematopoietic Cells to the Bone Marrow at JoVE.com

Homing of Hematopoietic Cells to the Bone Marrow

Questo articolo descrive un protocollo utilizzato per studiare l&#39;homing delle cellule ematopoietiche alla loro nicchie nel midollo osseo.

Homing delle cellule ematopoietiche del midollo osseo

Homing is the phenomenon whereby transplanted hematopoietic cells are able to travel to and engraft or establish residence in the bone marrow.  Various ...

homing-of-hematopoietic-cells-to-the-bone-marrow

Research

JoVE Journal

Biology

29.4K Views.  MGH - Massachusetts General Hospital. Questo articolo descrive un protocollo utilizzato per studiare l'homing delle cellule ematopoietiche alla loro nicchie nel midollo osseo.

Video: Homing of Hematopoietic Cells to the Bone Marrow

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.

Isolamento e analisi delle cellule staminali ematopoietiche dalla 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. ...

Ricerca

Biologia

Culture of myeloid dendritic cells from bone marrow precursors

Myeloid dendritic cells (DCs) are frequently used to study the interactions between innate and adaptive immune mechanisms and the early response to infection. Because these are the most potent antigen presenting cells, DCs are being increasingly used as a vaccine vector to study the induction of antigen-specific immune responses. In this video, we demonstrate the procedure for harvesting tibias and femurs from a donor mouse, processing the bone marrow and differentiating DCs in vitro. The properties of DCs change following stimulation: immature dendritic cells are potent phagocytes, whereas mature DCs are capable of antigen presentation and interaction with CD4+ and CD8+ T cells. This change in functional activity corresponds with the upregulation of cell surface markers and cytokine production. Many agents can be used to mature DCs, including cytokines and toll-like receptor ligands. In this video, we demonstrate flow cytometric comparisons of expression of two co-stimulatory molecules, CD86 and CD40, and the cytokine, IL-12, following overnight stimulation with CpG or mock treatment. After differentiation, DCs can be further manipulated for use as a vaccine vector or to generate antigen-specific immune responses by in vitro pulsing using peptides or proteins, or transduced using recombinant viral vectors. 

This video demonstrates the procedure for differentiating myeloid dendritic cells from mouse bone marrow. Isolation of mouse tibia and femur, and processing of bone marrow are demonstrated. Pictures demonstrating cell morphology before and after differentiation, and figures depicting cell phenotype and IL-12 production following maturation using CpG are shown.

Cultura di cellule dendritiche mieloidi dai precursori del midollo osseo

Myeloid dendritic cells (DCs) are frequently used to study the interactions between innate and adaptive immune mechanisms and the early response to ...

Generation of Bone Marrow Derived Murine Dendritic Cells for Use in 2-photon Imaging

Several methods for the preparation of murine dendritic cells can be found in the literature. Here, we present a method that produces greater than 85% CD11c high dendritic cells in culture that home to the draining lymph node after subcutaneous injection and present antigen to antigen specific T cells (see video). Additionally, we use Essen Instruments Incucyte to track dendritic cell maturation, where, at day 10, the morphology of the cultured cells is typical of a mature dendritic cell and &lt;85% of cells are CD11chigh. The study of antigen presentation in peripheral lymph nodes by 2-photon imaging revealed that there are three distinct phases of dendritic cell and T cell interaction1, 2. Phase I consists of brief serial contacts between highly motile antigen specific T cells and antigen carrying dendritic cells1, 2. Phase two is marked by prolonged contacts between antigen-specific T cell and antigen bearing dendritic cells1, 2. Finally, phase III is characterized by T cells detaching from dendritic cells, regaining motility and beginning to divide1, 2. This is one example of the type of antigen-specific interactions that can be analyzed by two-photon imaging of antigen-loaded cell tracker dye-labeled dendritic cells.

Antigen presentation in secondary lymphoid organs by dendritic cells is crucial for the initiation of the T cell mediated adaptive immune response. Here we demonstrate the culture of bone marrow derived murine dendritic cells, activation, and labeling for 2-photon imaging.

Generazione di cellule derivate dal midollo osseo dendritiche murini per l&#39;uso in 2-fotone Imaging

Several methods for the preparation of murine dendritic cells can be found in the literature. Here, we present a method that produces greater than 85% ...

The Preparation of Primary Hematopoietic Cell Cultures From Murine Bone Marrow for Electroporation

It is becoming increasingly apparent that electroporation is the most effective way to introduce plasmid DNA or siRNA into primary cells. The Gene Pulser MXcell  electroporation system and Gene Pulser  electroporation buffer were specifically developed to transfect nucleic acids into mammalian cells and difficult-to-transfect cells, such as primary and stem cells.This video demonstrates how to establish primary hematopoietic cell cultures from murine bone marrow, and then prepare them for electroporation in the MXcell system. We begin by isolating femur and tibia. Bone marrow from both femur and tibia are then harvested and cultures are established. Cultured bone marrow cells are then transfected and analyzed.

This procedure describes how to establish primary hematopoietic cell cultures from murine bone marrow and is followed by transfection using the Gene Pulser MXCell electroporation system.

La preparazione di colture primarie di cellule emopoietiche dal midollo osseo murino per elettroporazione

It is becoming increasingly apparent that electroporation is the most effective way to introduce plasmid DNA or siRNA into primary cells. The Gene Pulser ...

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.

Lentivirali-mediata Knockdown Durante Ex Vivo</emEritropoiesi> di cellule staminali emopoietiche

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

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.

In Vivo inseguimento 4-dimensionale di emopoietiche staminali e progenitrici celle di topo adulto cranica di Midollo Osseo

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

Osteoclast Derivation from Mouse Bone Marrow

Osteoclasts are highly specialized cells that are derived from the monocyte/macrophage lineage of the bone marrow. Their unique ability to resorb both the organic and inorganic matrices of bone means that they play a key role in regulating skeletal remodeling. Together, osteoblasts and osteoclasts are responsible for the dynamic coupling process that involves both bone resorption and bone formation acting together to maintain the normal skeleton during health and disease.
As the principal bone-resorbing cell in the body, changes in osteoclast differentiation or function can result in profound effects in the body. Diseases associated with altered osteoclast function can range in severity from lethal neonatal disease due to failure to form a marrow space for hematopoiesis, to more commonly observed pathologies such as osteoporosis, in which excessive osteoclastic bone resorption predisposes to fracture formation.
An ability to isolate osteoclasts in high numbers in vitro has allowed for significant advances in the understanding of the bone remodeling cycle and has paved the way for the discovery of novel therapeutic strategies that combat these diseases. 
Here, we describe a protocol to isolate and cultivate osteoclasts from mouse bone marrow that will yield large numbers of osteoclasts.

Osteoclasts are the principal bone-resorbing cell in the body. An ability to isolate osteoclasts in large numbers has resulted in significant advances in the understanding of osteoclast biology. In this protocol, we describe a method for isolation, cultivating and quantifying osteoclast activity in vitro.

Osteoclasti derivazione dal midollo osseo di topo

Osteoclasts are highly specialized cells that are derived from the monocyte/macrophage lineage of the bone marrow. Their unique ability to resorb both the ...

Expression of Fluorescent Fusion Proteins in Murine Bone Marrow-derived Dendritic Cells and Macrophages

Dendritic cells and macrophages are crucial cells that form the first line of defense against pathogens. They also play important roles in the initiation of an adaptive immune response. Experimental work with these cells is rather challenging. Their abundance in organs and tissues is relatively low. As a result, they cannot be isolated in large numbers. They are also difficult to transfect with cDNA constructs. In the murine model, these problems can be partially overcome by in vitro differentiation from bone marrow progenitors in the presence of M-CSF for macrophages or GM-CSF for dendritic cells. In this way, it is possible to obtain large amounts of these cells from very few animals. Moreover, bone marrow progenitors can be transduced with retroviral vectors carrying cDNA constructs during early stages of cultivation prior to their differentiation into bone marrow derived dendritic cells and macrophages. Thus, retroviral transduction followed by differentiation in vitro can be used to express various cDNA constructs in these cells. The ability to express ectopic proteins substantially extends the range of experiments that can be performed on these cells, including live cell imaging of fluorescent proteins, tandem purifications for interactome analyses, structure-function analyses, monitoring of cellular functions with biosensors and many others. In this article, we describe a detailed protocol for retroviral transduction of murine bone marrow derived dendritic cells and macrophages with vectors coding for fluorescently-tagged proteins. On the example of two adaptor proteins, OPAL1 and PSTPIP2, we demonstrate its practical application in flow cytometry and microscopy. We also discuss the advantages and limitations of this approach.

In this article, we provide a detailed protocol for the expression of fluorescent fusion proteins in murine bone marrow derived dendritic cells and macrophages. The method is based on the transduction of bone marrow progenitors with retroviral constructs followed by differentiation into macrophages and dendritic cells in vitro.

Espressione di proteine di fusione fluorescenti in macrofagi e cellule dendritiche derivate da midollo osseo Murine

Dendritic cells and macrophages are crucial cells that form the first line of defense against pathogens. They also play important roles in the initiation ...

Isolation, Purification, and Differentiation of Osteoclast Precursors from Rat Bone Marrow

Osteoclasts are large, multinucleated, and bone-resorbing cells of the monocyte-macrophage lineage that are formed by the fusion of monocytes or macrophage precursors. Excessive bone resorption is one the most significant cellular mechanisms leading to osteolytic diseases, including osteoporosis, periodontitis, and periprosthetic osteolysis. The main physiological function of osteoclasts is to absorb both the hydroxyapatite mineral component and the organic matrix of bone, generating the characteristic resorption appearance on the surface of bones. There are relatively few osteoclasts compared to other cells in the body, especially in adult bones. Recent studies have focused on how to obtain more mature osteoclasts in less time, which has always been a problem. Several improvements in the isolation and culture techniques have developed in laboratories in order to obtain more mature osteoclasts. Here, we introduce a method that isolates bone marrow in less time and with less effort compared to the traditional procedure, using a special and simple device. With the use of density gradient centrifugation, we obtain large amounts of fully differentiated osteoclasts from rat bone marrow, which are identified by classical methods.

Osteoclasts are tissue-specific macrophage polykaryons derived from the monocyte-macrophage lineage of hematopoietic stem cells. This protocol describes how to isolate bone marrow cells so that large quantities of osteoclasts are obtained while reducing the risk of accidents found in traditional methods.

Isolamento, purificazione e differenziazione dei precursori dell'osteoclast dal midollo osseo del ratto

Osteoclasts are large, multinucleated, and bone-resorbing cells of the monocyte-macrophage lineage that are formed by the fusion of monocytes or ...

Proplatelet Formation Dynamics of Mouse Fresh Bone Marrow Explants

The last stage of megakaryopoiesis leads to cytoplasmic extensions from mature megakaryocytes, the so-called proplatelets. Much has been learned about the proplatelet formation using in vitro-differentiated megakaryocytes; however, there is an increasing evidence that conventional culture systems do not faithfully recapitulate the differentiation/maturation process that takes places inside the bone marrow. In this manuscript, we present an explant method initially described in 1956 by Thi&#233;ry and Bessis to visualize megakaryocytes which have matured in their native environment, thus circumventing potential artifacts and misinterpretations. Fresh bone marrows are collected by flushing the femurs of mice, sliced into 0.5 mm cross sections, and placed in an incubation chamber at 37 &#176;C containing a physiological buffer. Megakaryocytes become gradually visible at the explant periphery and are observed up to 6 hours under an inverted microscope coupled to a video camera. Over time, megakaryocytes change their shape, with some cells having a spherical form and others developing thick extensions or extending many thin proplatelets with extensive branching. Both qualitative and quantitative investigations are carried out. This method has the advantage of being simple, reproducible, and fast as numerous megakaryocytes are present, and classically half of them form proplatelets in 6 hours compared to 4 days for cultured mouse megakaryocytes. In addition to the study of mutant mice, an interesting application of this method is the straightforward evaluation of the pharmacological agents on the proplatelet extension process, without interfering with the differentiation process that may occur in cultures.

Here, we detail the bone marrow explant method, from sample preparation to microscopic slide analysis, to evaluate the ability of megakaryocytes which have differentiated in their physiological environment to form proplatelets.

Dinamica di formazione dei proplatelet degli espianti di midollo osseo fresco del topo

The last stage of megakaryopoiesis leads to cytoplasmic extensions from mature megakaryocytes, the so-called proplatelets. Much has been learned about the ...