We are grateful to Drs. Markus Manz and Irving Weissman for providing reagents. We also acknowledge the service provided by the Flow Cytometric Analysis and Cell Sorting Core Facility of the First and Second Core Laboratory at National Taiwan University College of Medicine and NTU hospital, respectively. This work was supported by the Ministry of Science and Technology, Taiwan (MOST 102-2320-B-002-030-MY3) and the National Health Research Institutes, Taiwan (NHRI-EX102-10256SI and NHRI-EX103-10256SI).

C57BL/6 wild-type mice were purchased from the National Laboratory Animal Center (NLAC), Taiwan. All mice were bred and kept under specific pathogen-free conditions. Protocols and animal use procedures were reviewed and approved by the Institutional Animal Care and Use Committee of National Taiwan University College of Medicine (Permit Number: 20120075). In addition, researchers made every effort to reduce the potential for pain, suffering, or distress in the animals while performing experiments. All procedures described were carried out at ...

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G., Traver, D., Miyamoto, T., Weissman, I. L., Akashi, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dendritic+cell+potentials+of+early+lymphoid+and+myeloid+progenitors.">Dendritic cell potentials of early lymphoid and myeloid progenitors.</a> Blood. 97, 3333-3341 (2001).</li><li>D'Amico, A., Wu, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+early+progenitors+of+mouse+dendritic+cells+and+plasmacytoid+predendritic+cells+are+within+the+bone+marrow+hemopoietic+precursors+expressing+Flt3.">The early progenitors of mouse dendritic cells and plasmacytoid predendritic cells are within the bone marrow hemopoietic precursors expressing Flt3.</a> J. Exp. 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Here we describe an in vitro culture system for the robust generation of DCs, and pDCs in particular, from a small number of CLPs. The uniqueness of this culture system is due to the use of AC-6 cells, a stromal cell line, as feeders. This approach has been shown to provide not only the cytokines, such as IL-7, SCF, M-CSF and FL20, but also the cell-cell contact21 necessary to support DC development. AC-6 cells have been used previously to facilitate the study of in vitro DC develo...

Dendritic cells (DCs) are professional antigen-presenting cells that play an important role in controlling immune responses1. While DCs are heterogeneous, they can be broadly classified into two populations, conventional DCs (cDCs) and plasmacytoid DCs (pDCs)2,3. In addition to lymphoid organs, cDCs and pDCs are also found in tissues including lung, intestine, and skin2. The morphology of cDCs and pDCs differs, with cDCs exhibiting dendrite-like projections and the shape of pDCs being more plasma cell-like. In addition, the common mouse DC marker, CD11c, is more highly expressed on cDCs than on pDCs. Moreover, cDCs can be further divided into CD11b+CD24- cDCs and CD11b-CD24+ cDCs, both of which express higher levels of MHC class II and costimulatory molecules than do pDCs2. Mature pDCs, on the other hand, have been shown to selectively express Siglec-H and BST24. Functionally, cDCs are better antigen presenting cells than are pDCs; however, pDCs can produce a vast amount of type I interferon upon virus infection or inflammatory stimulation5.
Both cDCs and pDCs are short-lived, and therefore, must be constantly replenished from progenitors within the bone marrow (BM)6,7. Adoptive transfer of common myeloid progenitors (CMPs) and common lymphoid progenitors (CLPs) into lethally-irradiated mice demonstrates that cDCs and pDCs can be generated from both lineages8-10. However, there is a subset of pDCs that express RAG1/2 and possess rearranged D-J segments at the IgH locus11,12. These cells also share molecular similarities with B lymphocytes, including expression of the B220 marker, nucleic acid-sensing receptors (TLR7/TLR9), and transcription factors (Spib and Bcl11a)13, features all believed to be signatures of the lymphoid lineage. Therefore, CLPs may be good choices for in vitro generation of pDCs because of lineage similarity.
While the frequency of both cDCs and pDCs in humans and mice is very low6, DCs, particularly cDCs, can be generated in vitro from BM or progenitors in the presence of cytokines, such as GM-CSF11,14 or Flt3 ligand (FL) using feeder-free systems 11,15,16. Unfortunately, however, it is not possible to produce large numbers of pDCs in vitro using FL11,15,16. Previously we demonstrated that pDCs can be efficiently generated in vitro from CLPs using the AC-6 feeder system17. The advantage of using the AC-6 stromal cell line in the culture system is that it provides cell-cell contact and secretion of cytokines that support the generation of large numbers of pDCs from CLPs. Although production with this system is quite robust, careful replication of the procedures described below is required in order to ensure efficient generation of pDCs.

<table>
	<tbody>
		<tr>
			<td>Anti-mouse Ly6g/Ly6c (PE), clone RB6-8C5</td>
			<td>Biolegend</td>
			<td>108408</td>
			<td>linage marker</td>
		</tr>
		<tr>
			<td>Anti-mouse NK1.1 (PE), clone PK136</td>
			<td>Biolegend</td>
			<td>108708</td>
			<td>linage marker</td>
		</tr>
		<tr>
			<td>Anti-mouse&#160; CD11b (PE), cloneM1/70</td>
			<td>Biolegend</td>
			<td>101208</td>
			<td>linage marker</td>
		</tr>
		<tr>
			<td>Anti-mouse CD19 (PE), clone eBio1D3</td>
			<td>Biolegend</td>
			<td>115508</td>
			<td>linage marker</td>
		</tr>
		<tr>
			<td>Anti-mouse B220 (PE), clone RA3-6B2</td>
			<td>Biolegend</td>
			<td>103208</td>
			<td>linage marker/FACS</td>
		</tr>
		<tr>
			<td>Anti-mouse CD3 (PE), clone 17A2</td>
			<td>Biolegend</td>
			<td>100308</td>
			<td>linage marker</td>
		</tr>
		<tr>
			<td>Anti-mouse CD8a (PE), clone 53-6.7</td>
			<td>Biolegend</td>
			<td>100707</td>
			<td>linage marker</td>
		</tr>
		<tr>
			<td>Anti-mouse MHC-II (PE), clone NIMR-4</td>
			<td>Biolegend</td>
			<td>107608</td>
			<td>linage marker</td>
		</tr>
		<tr>
			<td>Anti-mouse Ter119 (PE), clone TER-119</td>
			<td>Biolegend</td>
			<td>116208</td>
			<td>linage marker</td>
		</tr>
		<tr>
			<td>Anti-mouse Thy1.1 (PE), clone HIS51</td>
			<td>eBioscience</td>
			<td>12-0900-83</td>
			<td>linage marker</td>
		</tr>
		<tr>
			<td>Anti-mouse M-CSFR (APC), clone AFS98</td>
			<td>Biolegend</td>
			<td>135510</td>
			<td>FACS</td>
		</tr>
		<tr>
			<td>Anti-mouse c-Kit (PerCP/Cy5.5), clone 2B8</td>
			<td>Biolegend</td>
			<td>105824</td>
			<td>FACS</td>
		</tr>
		<tr>
			<td>Anti-mouse Sca-1 (FITC), clone D7</td>
			<td>Biolegend</td>
			<td>108106</td>
			<td>FACS</td>
		</tr>
		<tr>
			<td>Anti-mouse IL-7Ra (PE/Cy7), clone A7R34</td>
			<td>Biolegend</td>
			<td>135014</td>
			<td>FACS</td>
		</tr>
		<tr>
			<td>Anti-mouse CD11c (PerCP/Cy5.5), clone N418</td>
			<td>Biolegend</td>
			<td>117328</td>
			<td>FACS</td>
		</tr>
		<tr>
			<td>Anti-mouse CD11b (FITC), clone M1/70</td>
			<td>Biolegend</td>
			<td>101206</td>
			<td>FACS</td>
		</tr>
		<tr>
			<td>FACSAria III</td>
			<td>BD Biosciences</td>
			<td></td>
			<td>Cell sorter</td>
		</tr>
		<tr>
			<td>FACS sorting tube&#160;</td>
			<td>BD Biosciences</td>
			<td>352054</td>
			<td></td>
		</tr>
		<tr>
			<td>FlowJo</td>
			<td>FlowJo LLC</td>
			<td></td>
			<td>Flow analysis sofrware</td>
		</tr>
	</tbody>
</table>

in vitro generation of murine plasmacytoid dendritic cells from common lymphoid progenitors using the ac-6 feeder system

Plasmacytoid dendritic cells (pDCs) are powerful type I interferon (IFN-I) producing cells that are activated in response to infection or during inflammatory responses. Unfortunately, study of pDC function is hindered by their low frequency in lymphoid organs, and existing methods for in vitro DC generation predominantly favor the production of cDCs over pDCs. Here we present a unique approach to efficiently generate pDCs from common lymphoid progenitors (CLPs) in vitro. Specifically, the protocol described details how to purify CLPs from bone marrow and generate pDCs by coculturing with &#947;-irradiated AC-6 feeder cells in the presence of Flt3 ligand. A unique characteristic of this culture system is that the CLPs migrate underneath the AC-6 cells and become cobblestone area-forming cells, a critical step for expanding pDCs. Morphologically distinct DCs, namely pDCs and cDCs, were generated after approximately 2 weeks with a composition of 70-90% pDCs under optimal conditions. Typically, the number of pDCs generated by this method is roughly 100-fold of the number of CLPs seeded. Therefore, this is a novel system with which to robustly generate the large numbers of pDCs required to facilitate further studies into the development and function of these cells.

A total of 4-6x107 BM cells are typically isolated from femurs and tibiae of one 6-8 wk-old, wild-type C57BL/6 mouse. To sort out CLPs, total BM cells are stained with PE-conjugated antibodies against lineage markers (CD3, CD8, B220, CD19, CD11b, Gr-1, Thy1.1, NK1.1, TER119, and MHC-II), anti-c-Kit-PerCP/Cy5.5, anti-Sca-1-FITC, anti-M-CSFR-APC and anti-IL-7R&#945;-PE/Cy7, analyzed and sorted with a cell sorter. The sorting strategy for CLP is shown in Figure 1. Typically, 5x104 CLPs...

Watch this Scientific Journal Video about In Vitro Generation of Murine Plasmacytoid Dendritic Cells from Common Lymphoid Progenitors using the AC-6 Feeder System at JoVE.com

In Vitro Generation of Murine Plasmacytoid Dendritic Cells from Common Lymphoid Progenitors using the AC-6 Feeder System

In this study we present an in vitro culture system that can efficiently generate pDCs by co-culturing common lymphoid progenitors with AC-6 feeder cells in the presence of Flt3 ligand.

In Vitro Generation of Murine Plasmacytoid Dendritic Cells from Common Lymphoid Progenitors using the AC-6 Feeder System

Plasmacytoid dendritic cells (pDCs) are powerful type I interferon (IFN-I) producing cells that are activated in response to infection or during ...

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8.3K Views.  National Taiwan University College of Medicine. In this study we present an in vitro culture system that can efficiently generate pDCs by co-culturing common lymphoid progenitors with AC-6 feeder cells in the presence of Flt3 ligand. 