This work was supported by Program of Tianjin Science and Technology Plan (20JCQNJC00550), Tianjin Health Science and Technology Project (TJWJ202021QN033 and TJWJ202021QN034).

All procedures were approved by the Nanjing Medical University Animal Care and Use Committee.
1. Isolation of bone marrow and preparation of BM cells
<ol>
	<li>Sacrifice C57BL/6 mice (18-22 g, 6-8 weeks old) via CO2 asphyxiation. Fix the mouse on the mouse operating table. Disinfect the surfaces with 70% ethanol.</li>
	<li>Cut the skin of the leg to expose the muscles and femoral artery. Clamp and tear off the femoral artery using two forceps, then pull the proximal end toward the abdomen. 
	NOTE: Do not cut the femoral artery directly. Otherwise, it will cause excessive bleeding and contaminate the field of vision.</li>
	<li>Cut all the muscles around the femur.</li>
	<li>Slowly stretch the lower limbs of the mouse outward until the sound of hip joint dislocation is heard and the femoral head prolapse is visible.</li>
	<li>Separate the lower limbs from the body using scissors along the inside of the femoral head.</li>
	<li>Cut the hind legs from the end of the knee joint to obtain a free and complete femur.</li>
	<li>Remove the muscles attached to the femur using gauze. 
	NOTE: Do not tear the muscles directly. The femur of mice is delicate, its integrity must be maintained.</li>
	<li>Immerse the femur in 75% alcohol for 2-5 min.</li>
</ol>
2. Induction culture of BMDC
<ol>
	<li>Rinse the residual alcohol with PBS. Use hemostatic forceps to clamp the middle and bottom part of the femur and another set to clamp the lower end of the femur. The hemostatic forceps are applied laterally to the femur, and the femur is separated from the epiphyseal line. 
	NOTE: The epiphyseal line is not easily visible until the femur fractures. This and the next steps are all performed in a sterile environment.</li>
	<li>Use a 1 mL syringe (needle: 0.6 mm x 25 mm) to penetrate the bone marrow cavity from the epiphyseal line break and rotate the needle to penetrate the femoral head and through the bone marrow cavity. Pulse and flush the bone marrow cavity using 1 mL of the complete medium containing GM-CSF/IL-4 until the bone becomes white. 
	NOTE: Complete culture medium: 10% FBS, 1% penicillin-streptomycin, 55 &#181;M &#946;-Mercaptoethanol, 10 ng/mL GM-CSF, and 10 ng/mL IL-4.</li>
	<li>Resuspend all the cells in 24 mL of complete culture medium (~5 x 105 cells/mL). After mixing, all the medium was seeded on a 6-well plate with 4 mL/well, then incubated at 37 &#176;C with 5% CO2 for 2 days. 
	NOTE: It is not necessary to lyse erythrocytes.</li>
	<li>Replace all the medium after 2 days with medium containing GM-CSF/IL-47. On the fourth, sixth, and eighth days, replace half of the medium with the complete medium containing 10 ng/mL GM-CSF/IL-4. 
	NOTE: In this step, suspended cells such as erythrocytes and lymphocytes are removed.</li>
	<li>Take pictures every day to record cell growth. Starting from day six, harvest one well of cells per day to count the cell number and detect CD11c, CD80, and MHC II expression6,7.</li>
</ol>
3. Flow cytometric detection of the expression of CD11c, CD80, and MHC II
<ol>
	<li>After washing the DCs with PBS, resuspend 1 x 106 cells in 100 &#181;L of FACS buffer, add 0.5 &#181;g of anti-mouse CD16/32 antibody, and incubate for 10 min on ice to block non-specific antigen sites.</li>
	<li>Add 1 &#181;g of Percp/cy5.5-CD11c, 0.5 &#181;g of PE-CD80, and 0.04 &#181;g of APC-MHC II antibodies, and incubate on ice for 30 min.</li>
	<li>Centrifuge at 1,000 x g for 3 min at 4 &#176;C, remove the supernatant, add 1 mL of 4% paraformaldehyde, fix for 30 min at 4 &#176;C, and re-suspend in 300 &#181;L of FACS buffer.</li>
	<li>Perform flow cytometry.</li>
</ol>

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M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dendritic+cells+and+the+control+of+immunity.">Dendritic cells and the control of immunity.</a> Nature. 392 (6673), 245-252 (1998).</li><li>Jiang, P. 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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=An+advanced+culture+method+for+generating+large+quantities+of+highly+pure+dendritic+cells+from+mouse+bone+marrow.">An advanced culture method for generating large quantities of highly pure dendritic cells from mouse bone marrow.</a> Journal of Immunological Methods. 223 (1), 77-92 (1999).</li><li>Son, Y. 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A., 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=Post-prandial+administration+of+the+insulin+analogue+insulin+aspart+in+patients+with+type+1+diabetes+mellitus.">Post-prandial administration of the insulin analogue insulin aspart in patients with type 1 diabetes mellitus.</a> Diabetic Medicine. 17 (5), 371-375 (2000).</li><li>Koido, 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=Induction+of+antitumor+immunity+by+vaccination+of+dendritic+cells+transfected+with+MUC1+RNA.">Induction of antitumor immunity by vaccination of dendritic cells transfected with MUC1 RNA.</a> Journal of Immunology. 165 (10), 5713-5719 (2000).</li><li>Jonasson, P. 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=Strength+of+the+porcine+proximal+femoral+epiphyseal+plate:+The+effect+of+different+loading+directions+and+the+role+of+the+perichondrial+fibrocartilaginous+complex+and+epiphyseal+tubercle+-+An+experimental+biomechanical+study.">Strength of the porcine proximal femoral epiphyseal plate: The effect of different loading directions and the role of the perichondrial fibrocartilaginous complex and epiphyseal tubercle - An experimental biomechanical study.</a> Journal of Experimental Orthopaedics. 1 (1), 4 (2014).</li><li>Labeur, M. 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All authors declare they have no conflicts of interest and that they have nothing to disclose.

Humans and mice have different DC subsets, including classical DCs (cDCs, including cDC1s and cDC2s) plasmacytoid DCs (pDCs), and monocyte-derived DCs (MoDCs)9,10,11. It is generally accepted that cDC1s regulate cytotoxic T lymphocyte (CTL) responses to intracellular pathogens and cancer, and cDC2s regulate immune responses to extracellular pathogens, parasites, and allergens12. A significant number of DCs can be produced in vitro from BM progenitor cells in mice in the presence of GM-CSF and IL-46,13,14. The purity and quantity of DCs play key roles in successful DC immunotherapy. Researchers have shown that two doses of 1 x 105 to 1 x 106 DCs could elicit efficient cytotoxic T lymphocyte (CTL) responses in a xenograft model15,16,17,18. This implies that a high number of high-purity DCs need to be cultivated to further investigate the role of DCs in tumor immunotherapy.
The traditional method of obtaining bone marrow cells is to cut the two ends of the femur and rinse with the medium6,7. In this study, we innovatively used physiological anatomical structures to sever the femur. Hemostatic forceps were used to clamp the lower end of the femur and move it laterally.The epiphyseal line is physiologically weak, making them susceptible to fractures when stressed19. After the femur is separated from the epiphyseal line, a small quantity of bone remains in the marrow cavity. The needle can easily penetrate the bone into the bone marrow cavity. The method is simple to operate, protects precious bone marrow cells, and provides a cellular basis for the culture of a high number of DCs. We cultured the DCs using a combination of 10 ng/mL GM-CSF and 10 ng/mL IL-4, which contributes more to the maturation of DCs than GM-CSF alone. Labeur and Son reported that the combined use of GM-CSF and IL-4 in the medium of DCs induced higher expression of maturation markers, such as IFN-&#611;, TNF-&#945;, and IL-6, and enhanced antigen-presenting ability7,20,21. Son et al. also proposed that the combination of GM-CSF and IL-4 promotes the maturation of DCs7,21.
In this study, we directly cultured the collected bone marrow cells without lysing the erythrocytes and separated them by gradient centrifugation, which may result in cell loss and, ultimately, to a reduction in harvested DCs. Before the medium was changed, there were several suspending cells in the culture system, including erythrocytes, T cells, B cells, and granulocytes. During co-culture, these cells may produce cytokines to promote the maturation of DCs.
In terms of limitations, this protocol only used two femurs of the mouse, excluding the smaller tibias, resulting in the loss of some mesenchymal stem cells. In short, we developed a cost-effective and efficient protocol for the isolation and generation of bone-marrow-derived dendritic cells from mice, which takes only 10 min to separate bone marrow cells. A large number of high-purity DCs were harvested after 6 days to 7 days of incubation with 10 ng/mL of GM-CSF and IL-4.

Dendritic cells (DCs) are the most powerful antigen-presenting cells (APCs) for activating na&#239;ve T cells and inducing specific cytotoxic T lymphocyte (CTL) responses against infectious diseases, allergy diseases, and tumor cells1,2,3. DCs are the primary link between innate immunity and adaptive immunity and play an essential role in immunological defense and the maintenance of immune tolerance. In the last 40 years, many researchers have sought to define the subsets of DCs and their functions in inflammation and immunity. As per those studies, DCs develop along the myeloid and lymphoid lineages from bone marrow cells. Tumor vaccines have gained significant milestones in recent years and have a promising future. Mechanically, tumor vaccines modulate the immune response and prevent tumor growth by activating cytotoxic T lymphocytes using tumor antigens. The vaccine based on DCs plays an important role in tumor immunotherapy and has been identified as one of the most promising anti-tumor therapies1,4. In addition, DCs have been widely used in the testing of new molecular-targeted drugs and immune checkpoint inhibitors5.
Researchers urgently need a high number of high-purity DCs to further study the role of DCs. However, DCs are rare in various tissues and blood, accounting for only 1% of blood cells in humans and animals. In vitro culture of bone marrow dendritic cells (BMDC) is an important method for obtaining large amounts of DC cells. Meanwhile, The Lutz protocol for generating DCs from bone marrow has been widely used by researchers6. Although the protocol is effective in obtaining DC cells, it is complex and expensive, involving the addition of high concentrations of cytokines and the lysis of red blood cells.
In this study, we report a method for isolating almost all bone marrow cells from mouse bone marrow (BM) and inducing differentiation into BMDC after 7-9 days of incubation in vitro, with a lower concentration of GM-CSF and IL-4. This procedure only takes 10 min to harvest almost all bone marrow cells and to suspend them in a complete medium. In brief, we provide an efficient and cost-effective culturing method for BMDC in this research.

<table><tbody><tr><td>&amp;beta;-Mercaptoethanol</td><td>Solarbio</td><td>M8211</td><td></td></tr><tr><td>6-well plate</td><td>Corning</td><td>3516</td><td></td></tr><tr><td>APC-MHC II</td><td>Biolegend</td><td>116417</td><td></td></tr><tr><td>FBS</td><td>Gibco</td><td>10100</td><td></td></tr><tr><td>PE-CD80</td><td>Biolegend</td><td>104707</td><td></td></tr><tr><td>Penicillin-Streptomycin</td><td>Solarbio</td><td>P1400</td><td></td></tr><tr><td>Percp/cy5.5-CD11c</td><td>Biolegend</td><td>117327</td><td></td></tr><tr><td>PRMI-1640</td><td>Thermo</td><td>11875093</td><td></td></tr><tr><td>Recombinant Mouse GM-CSF</td><td>Solarbio</td><td>P00184</td><td></td></tr><tr><td>Recombinant Mouse IL-4</td><td>Solarbio</td><td>P00196</td><td></td></tr><tr><td>TruStain Fc PLUS (anti-mouse CD16/32) Antibody</td><td>Biolegend</td><td>156603</td><td></td></tr></tbody></table>

economical and efficient protocol for isolating and culturing bone marrow-derived dendritic cells from mice

The demand for dendritic cells (DCs) is gradually increasing as immunology research advances. However, DCs are rare in all tissues. The traditional method for isolating DCs primarily involves inducing bone marrow (BM) differentiation into DCs by injecting large doses (&#62;10 ng/mL) of granulocyte-macrophage colony-stimulating factor/interleukin-4 (GM-CSF/IL-4), making the procedure complex and expensive. In this protocol, using all BM cells cultured in 10 ng/mL GM-CSF/IL-4 medium, after 3-4 half-culture exchanges, up to 2.7 x 107 CD11c+ cells&#160;(DCs) per mouse (two femurs) were harvested with a purity of 80%-95%. After 10 days in culture, the expression of CD11c, CD80, and MHC II increased, whereas the number of cells decreased. The number of cells peaked after 7 days of culture. Moreover, this method only took 10 min to harvest all bone marrow cells, and a high number of DCs were obtained after 1 week of culture.

The 1 x 107-1.7 x 107 cells were extracted from two femurs and were re-suspended in 24 mL of medium before being planted in a 6-well plate (Figure 1A). After 2 days, non-adherent cells were removed by completely changing the culture medium. Before changing the medium, a significant number of suspended cells were observed (Figure 1B). After 3 days of culture, small cell colonies began to form. On the sixth day, the size and number of colonies increased significantly. On the seventh day, the number of cells peaked (22 x 106-27 x 106) and then dropped gradually (Figure 2A). The surface of the DC cells became rough with longer pseudopodia, exhibiting typical mature DC cell morphology (Figure 2B). Flow cytometric analysis showed that the ratio of CD11c positive to total cells was 71% on the sixth day, whereas the ratio increased to 96.1% on the tenth day (Figure 2C,2D).
To evaluate the expression of co-stimulatory molecules, CD11c, CD80, and MHC II were co-stained8. As shown as Figure 3A, the expression of CD11c, CD80, and MHC II gradually increased with increasing cultivation time from day 6 to day 10. Additionally, flow cytometric analysis showed a gradual increase in the proportions of CD11c and CD80 double-positive, CD11c and MHCII double-positive (Figure 3B,3D), and triple-positive cells (Figure 3C,3D).
<img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/63125/63125fig01.jpg" /> 
Figure 1: Representative images of DCs at different culture times. (A) Flow-chart of culturing BMDC. (B) Representative images of DCs at different culture times. Bone marrow cells were suspended in 24 mL of culture medium with 10 ng/mL GM-CSF and IL-4 and seeded in a 6-well plate. BF, before changing culture medium; AF, after changing culture medium. Red arrow, DC colony. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/63125/63125fig01large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 2" class="xfigimg" src="/files/ftp_upload/63125/63125fig02.jpg" /> 
Figure 2: The number and purity of DCs at different culture times. (A) Total number of cells in all culture medium. (B) Representative images of DCs. (C,D) Flow cytometric and graphical representation of the analysis of the proportion of DCs. Positive cells were sorted by CD11c. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/63125/63125fig02large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 3" class="xfigimg" src="/files/ftp_upload/63125/63125fig03.jpg" /> 
Figure 3: The expression of co-stimulatory molecules in DCs. (A) The expression of CD11c, CD80, and MHC &#921;&#921; in DCs. (B) Flow cytometric analysis of the proportion of CD11c and CD80 double-positive, CD11c and MHC &#921;&#921; double-positive, and triple-positive cells. (C, D) Flow cytometric analysis from Day 6- Day 10 and graphical representation to show the statistical analysis. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/63125/63125fig03large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>

Watch this Scientific Journal Video about Economical and Efficient Protocol for Isolating and Culturing Bone Marrow-derived Dendritic Cells from Mice at JoVE.com

Economical and Efficient Protocol for Isolating and Culturing Bone Marrow-derived Dendritic Cells from Mice

Here, we present an economical and efficient method to isolate and generate high-purity bone marrow-derived dendritic cells from mice after 7 days of culture with 10 ng/mL GM-CSF/IL-4.

The demand for dendritic cells (DCs) is gradually increasing as immunology research advances. However, DCs are rare in all tissues. The traditional method ...

economical-efficient-protocol-for-isolating-culturing-bone-marrow

Nanyang Technological University

Research

JoVE Journal

Immunology and Infection

8.3K Views.  The Second Hospital of Tianjin Medical University. Here, we present an economical and efficient method to isolate and generate high-purity bone marrow-derived dendritic cells from mice after 7 days of culture with 10 ng/mL GM-CSF/IL-4.

Video: Economical and Efficient Protocol for Isolating and Culturing Bone Marrow-derived Dendritic Cells from Mice

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.

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

Biology

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.

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

Isolation, Purification and Labeling of Mouse Bone Marrow Neutrophils for Functional Studies and Adoptive Transfer Experiments

Neutrophils are critical effector cells of the innate immune system. They are rapidly recruited at sites of acute inflammation and exert protective or pathogenic effects depending on the inflammatory milieu. Nonetheless, despite the indispensable role of neutrophils in immunity, detailed understanding of the molecular factors that mediate neutrophils' effector and immunopathogenic effects in different infectious diseases and inflammatory conditions is still lacking, partly because of their short half life, the difficulties with handling of these cells and the lack of reliable experimental protocols for obtaining sufficient numbers of neutrophils for downstream functional studies and adoptive transfer experiments. Therefore, simple, fast, economical and reliable methods are highly desirable for harvesting sufficient numbers of mouse neutrophils for assessing functions such as phagocytosis, killing, cytokine production, degranulation and trafficking. To that end, we present a reproducible density gradient centrifugation-based protocol, which can be adapted in any laboratory to isolate large numbers of neutrophils from the bone marrow of mice with high purity and viability. Moreover, we present a simple protocol that uses CellTracker dyes to label the isolated neutrophils, which can then be adoptively transferred into recipient mice and tracked in several tissues for at least 4 hr post-transfer using flow cytometry. Using this approach, differential labeling of neutrophils from wild-type and gene-deficient mice with different CellTracker dyes can be successfully employed to perform competitive repopulation studies for evaluating the direct role of specific genes in trafficking of neutrophils from the blood into target tissues in vivo.

We describe a protocol for isolation and purification of neutrophils from mouse bone marrow by density gradient centrifugation and for neutrophil labeling using CellTracker dyes. This represents a simple, fast, reproducible and economical method for obtaining large numbers of neutrophils for downstream functional studies or adoptive transfer and tracking experiments.

Neutrophils are critical effector cells of the innate immune system. They are rapidly recruited at sites of acute inflammation and exert protective or ...

Isolation and Intravenous Injection of Murine Bone Marrow Derived Monocytes

As a subtype of leukocytes and progenitors of macrophages, monocytes are involved in many important processes of organisms and are often the subject of various fields in biomedical science. The method described below is a simple and effective way to isolate murine monocytes from heterogeneous bone marrow.
Bone marrow from the femur and tibia of Balb/c mice is harvested by flushing with phosphate buffered saline (PBS). Cell suspension is supplemented with macrophage-colony stimulating factor (M-CSF) and cultured on ultra-low attachment surfaces to avoid adhesion-triggered differentiation of monocytes. The properties and differentiation of monocytes are characterized at various intervals. Fluorescence activated cell sorting (FACS), with markers like CD11b, CD115, and F4/80, is used for phenotyping. At the end of cultivation, the suspension consists of 45%&#177; 12% monocytes. By removing adhesive macrophages, the purity can be raised up to 86%&#177; 6%. After the isolation, monocytes can be utilized in various ways, and one of the most effective and common methods for in vivo delivery is intravenous tail vein injection. 
This technique of isolation and application is important for mouse model studies, especially in the fields of inflammation or immunology. Monocytes can also be used therapeutically in mouse disease models.

Here we present a protocol that generates large amounts of murine monocytes from heterogeneous bone marrow for translational applications. In comparison to others, this new method helps reduce the number of sacrificed animals and lowers costs by avoiding expensive methods such as high gradient magnetic cell separation (MACS).

As a subtype of leukocytes and progenitors of macrophages, monocytes are involved in many important processes of organisms and are often the subject of ...

An Efficient and High Yield Method for Isolation of Mouse Dendritic Cell Subsets

Dendritic cells (DCs) are professional antigen-presenting cells primarily responsible for acquiring, processing and presenting antigens on antigen presenting molecules to initiate T-cell-mediated immunity. Dendritic cells can be separated into several phenotypically and functionally heterogeneous subsets. Three important subsets of splenic dendritic cells are plasmacytoid, CD8&#945;Pos and CD8&#945;Neg cells. The plasmacytoid DCs are natural producers of type I interferon and are important for anti-viral T cell immunity. The CD8&#945;Neg DC subset is specialized for MHC class II antigen presentation and is centrally involved in priming CD4 T cells. The CD8&#945;Pos DCs are primarily responsible for cross-presentation of exogenous antigens and CD8 T cell priming. The CD8&#945;Pos DCs have been demonstrated to be most efficient at the presentation of glycolipid antigens by CD1d molecules to a specialized T cell population known as invariant natural killer T (iNKT) cells. Administration of Flt-3 ligand increases the frequency of migration of dendritic cell progenitors from bone marrow, ultimately resulting in expansion of dendritic cells in peripheral lymphoid organs in murine models. We have adapted this model to purify large numbers of functional dendritic cells for use in cell transfer experiments to compare in vivo proficiency of different DC subsets.

Distinct dendritic cell subsets exist as rare populations in lymphoid organs, and therefore are challenging to isolate in sufficient numbers and purity for immunological experiments. Here we describe a high efficiency, high yield method for isolation of all of the currently known major subsets of mouse splenic dendritic cells.

Dendritic cells (DCs) are professional antigen-presenting cells primarily responsible for acquiring, processing and presenting antigens on antigen ...

Fluorescence-activated Cell Sorting for Purification of Plasmacytoid Dendritic Cells from the Mouse Bone Marrow

Fluorescence-activated cell sorting (FACS) is a technique to purify specific cell populations based on phenotypes detected by flow cytometry. This method enables researchers to better understand the characteristics of a single cell population without the influence of other cells. Compared to other methods of cell enrichment, such as magnetic-activated cell sorting (MCS), FACS is more flexible and accurate for cell separation due to the ability of phenotype detection by flow cytometry. In addition, FACS is usually capable of separating multiple cell populations simultaneously, which improves the efficiency and diversity of experiments. Although FACS has some limitations, it has been broadly used to purify cells for functional studies in both in vitro and in vivo settings. Here we report a protocol using fluorescence-activated cell sorting to isolate a very rare population of immune cells, plasmacytoid dendritic cells (pDC), with high purity from the bone marrow of lupus-prone mice for in vitro functional studies of pDC.

We report a protocol using fluorescence-activated cell sorting to isolate plasmacytoid dendritic cells (pDC) with high purity from the bone marrow of lupus-prone mice for functional studies of pDC.

Fluorescence-activated cell sorting (FACS) is a technique to purify specific cell populations based on phenotypes detected by flow cytometry. This method ...

Development and Functional Characterization of Murine Tolerogenic Dendritic Cells

The immune system operates by maintaining a tight balance between coordinating responses against foreign antigens and maintaining an unresponsive state against self-antigens as well as antigens derived from commensal organisms. The disruption of this immune homeostasis can lead to chronic inflammation and to the development of autoimmunity. Dendritic cells (DCs) are the professional antigen-presenting cells of the innate immune system involved in activating na&#239;ve T cells to initiate immune responses against foreign antigens. However, DCs can also be differentiated into TolDCs that act to maintain and promote T cell tolerance and to suppress effector cells contributing to the development of either autoimmune or chronic inflammation conditions. The recent advancement in our understanding of TolDCs suggests that DC tolerance can be achieved by modulating their differentiation conditions. This phenomenon has led to tremendous growth in developing TolDC therapies for numerous immune disorders caused due to break in immune tolerance. Successful studies in preclinical autoimmunity murine models have further validated the immunotherapeutic utility of TolDCs in the treatment of autoimmune disorders. Today, TolDCs have become a promising immunotherapeutic tool in the clinic for reinstating immune tolerance in various immune disorders by targeting pathogenic autoimmune responses while leaving protective immunity intact. Although an array of strategies has been proposed by multiple labs to induce TolDCs, there is no consistency in characterizing the cellular and functional phenotype of these cells. This protocol provides a step-by-step guide for the development of bone marrow-derived DCs in large numbers, a unique method used to differentiate them into TolDCs with a synthetic triterpenoid 2-cyano-3,12-dioxooleana-1,9-dien-28-oic acid-difluoro-propyl-amide (CDDO-DFPA), and the techniques used to confirm their phenotype, including analyses of essential molecular signatures of TolDCs. Finally, we show a method to assess TolDC function by testing their immunosuppressive response in vitro and in vivo in a preclinical model of multiple sclerosis.

Here, we present a protocol to develop and characterize tolerogenic dendritic cells (TolDCs) and evaluate their immunotherapeutic utility.

The immune system operates by maintaining a tight balance between coordinating responses against foreign antigens and maintaining an unresponsive state ...

Medicine

A Comprehensive High-Efficiency Protocol for Isolation, Culture, Polarization, and Glycolytic Characterization of Bone Marrow-Derived Macrophages

Macrophages are among the most important antigen-presenting cells. Many subsets of macrophages have been identified with unique metabolic signatures. Macrophages are commonly classified as M1-like (inflammatory) and M2-like (anti-inflammatory) subtypes. M1-like macrophages are pro-inflammatory macrophages that get activated by LPS and/or pro-inflammatory cytokines such as INF-&#947;, IL-12 &#38; IL-2. M1-like polarized macrophages are involved in various diseases by mediating the host&#39;s defense to a variety of bacteria and viruses. That is very important to study LPS induced M1-like macrophages and their metabolic states in inflammatory diseases. M2-like macrophages are considered anti-inflammatory macrophages, activated by anti-inflammatory cytokines and stimulators. Under the pro-inflammatory state, macrophages show increased glycolysis in glycolytic function. The glycolytic function has been actively investigated in the context of glycolysis, glycolytic capacity, glycolytic reserve, compensatory glycolysis, or non-glycolytic acidification using extracellular flux (XF) analyzers.
This paper demonstrates how to assess the glycolytic states in real-time with easy-to-follow steps when the bone marrow-derived macrophages (BMDMs) are respiring, consuming, and producing energy. Using specific inhibitors and activators of glycolysis in this protocol, we show how to obtain a systemic and complete view of glycolytic metabolic processes in the cells and provide more accurate and realistic results. To be able to measure multiple glycolytic phenotypes, we provide an easy, sensitive, DNA-based normalization method for polarization assessment of BMDMs. Culturing, activation/polarization and identification of the phenotype and metabolic state of the BMDMs are crucial techniques that can help to investigate many different types of diseases.
In this paper, we polarized the na&#239;ve M0 macrophages to M1-like and M2-like macrophages with LPS and IL4, respectively, and measured a comprehensive set of glycolytic parameters in BMDMs in real-time and longitudinally over time, using extracellular flux analysis and glycolytic activators and inhibitors.

This protocol provides detailed and comprehensive methods for the isolation, culture, polarization, and measurement of the glycolytic metabolic state of live bone marrow-derived macrophages (BMDMs). This paper provides step-by-step instructions with realistic visual illustrations for workflow and glycolytic assessment of BMDMs in real-time.

Macrophages are among the most important antigen-presenting cells. Many subsets of macrophages have been identified with unique metabolic signatures. ...

Isolation and Culture of Bone Marrow-Derived Macrophages from Mice

Macrophages have important effector functions in homeostasis and inflammation. These cells are present in every tissue in the body and have the important ability to change their profile according to the stimuli present in the microenvironment. Cytokines can profoundly affect macrophage physiology, especially IFN-&#947; and interleukin 4, generating M1 and M2 types respectively. Because of the versatility of these cells, the production of a population of bone marrow-derived macrophages can be a basic step in many experimental models of cell biology. The aim of this protocol is to help researchers in the isolation and culture of macrophages derived from bone marrow progenitors. Bone marrow progenitors from pathogen-free C57BL/6 mice are transformed into macrophages upon exposure to macrophage colony-stimulating factor (M-CSF) that, in this protocol, is obtained from the supernatant of the murine fibroblast lineage L-929. After incubation, mature macrophages are available for use from the 7th to the 10th day. A single animal can be the source of approximately 2 x 107 macrophages. Therefore, it is an ideal protocol for obtaining large amounts of primary macrophages using basic methods of cell culture.

The present protocol describes the isolation and culture of bone marrow-derived macrophages from mice.

Macrophages have important effector functions in homeostasis and inflammation. These cells are present in every tissue in the body and have the important ...

Isolation And Dendritic Cell-Uptake of Small Extracellular Vesicles from Echinococcus granulosus

The secretion of extracellular vesicles by cestodes is crucial for enabling cellular communication not only among parasites but also with host tissues. In particular, small extracellular vesicles (sEVs) act as nano-carriers transferring natural antigens, which are critical in host immunomodulation and parasite survival. This article presents a step-by-step protocol to isolate sEVs from larval stage cultures of Echinococcus granulosus and analyzes their uptake by dendritic cells obtained from murine bone marrow, which acquire adhesion and antigen presentation capacity during their maturation after one week of in vitro culture. This article provides comprehensive information for generating, purifying, and quantifying sEVs using ultracentrifugation alongside parallel analyses of dynamic light scattering and transmission electron microscopy. Additionally, a detailed experimental protocol is outlined for isolating and cultivating mouse bone marrow cells and driving their differentiation into dendritic cells using Flt3L. These dendritic cells can present antigens to na&#239;ve T cells, thereby modulating the type of immune response in vivo. Thus, alternative protocols, including confocal microscopy and flow cytometry analysis, are proposed to check the acquired maturational phenotype of dendritic cells previously exposed to parasitic sEVs. Finally, it is worth noting that the described protocol can be applied as a whole or in individual parts to carry out parasite in vitro culture, isolate extracellular vesicles, generate bone marrow-derived dendritic cell cultures, and perform uptake assays with these cells.

Here, we describe in vitro culture conditions, isolation, and increased generation of extracellular vesicles (EVs) from Echinococcus granulosus. The small EVs were characterized by dynamic light scattering and transmission electron microscopy. The uptake by bone marrow-derived dendritic cells and their phenotypic modulation were studied using confocal microscopy and flow cytometry.

The secretion of extracellular vesicles by cestodes is crucial for enabling cellular communication not only among parasites but also with host tissues. In ...