Name: assessment of the immunomodulatory properties of human mesenchymal stem cells (mscs)
Uploaded: 2015-12-24T14:00:00
Description: Watch this Scientific Journal Video about Assessment of the Immunomodulatory Properties of Human Mesenchymal Stem Cells MSCs at JoVE.com

This work was supported in part by grants from NHRI (CS-104-PP-06 to B.L.Y.).

Patient informed consent as approved by the institutional review board must be obtained for use of human cells.
1. Density Gradient Isolation of Human Peripheral Blood Mononuclear Cells (PBMCs)
<ol>
	<li>Add 25 ml heparinized whole blood into a 50 ml tube by a 25 ml pipette.
	<ol>
		<li>Dilute cells with 25 ml of phosphate-buffered saline (PBS).</li>
	</ol>
	</li>
	<li>Add 15 ml of Ficoll-Paque density gradient into a new 50 ml tube, and while tilting the tube, very slowly and carefully add ...

<ol>
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Increasingly, the immunomodulatory properties of MSCs are being translated into clinical use more rapidly than the multilineage capacity of these stem cells18-20. Thus, co-culture techniques of MSCs with leukocytes and assays to evaluate immune function are important to further delineate the specific mechanisms involved in these properties for optimizing effective therapeutic application. 
One of the most critical technical aspects for success in these assays is having adequate PBMC...

Human mesenchymal stem cells (MSCs) are somatic progenitors that can differentiate into the paraxial mesodermal lineages of bone, cartilage, and adipose tissue1-4, as well as to a few extramesodermal lineages5. First isolated from the adult bone marrow, these multilineage progenitors have now been found in numerous tissues6-8 and, unexpectedly, shown to have strong immunomodulatory properties that appear highly amenable to clinical application9-12. Detailed mechanisms involved in the immunomodulatory effects are actively being investigated for effective application on specific disease entities. One of the most straightforward ways to evaluate immunomodulation is by assessing for the suppression of effector leukocyte proliferation13. Most effector leukocytes such as T lymphocytes and monocytes proliferate prodigiously when stimulated or activated. Immunomodulatory function can be assessed when suppression of proliferation is evidenced.
Traditionally, effector leukocyte proliferation has been evaluated by detection of [3H] thymidine incorporation into DNA. However, this method has significant drawbacks due to the concerns of radiation and post-use disposal, as well as the complex equipment needed. While there are non-radioactive assays to assess cell proliferation, the carboxyfluorescein succinimidyl ester (CFSE) assay has other advantages such as allowing for identification of specific cellular populations, which is especially useful in co-culture experiments involving multiple cell types. CFSE is a fluorescent cellular dye which can be assessed by flow cytometric analysis. As cells divide, the intensity of this cellular label is decreased proportionally; this not only enables determination of overall cell proliferation but also allows for the assessment on the number of cell divisions up to 8 divisions before the fluorescence becomes difficult to detect against background signal. Moreover, the stability of the fluorescent CFSE allows for in vivo tracking of labeled cells such that cells can be visualized up to many months14.
This assay can also be varied to evaluate specific types of effector leukocytes or the immunomodulatory function of specific populations of MSC-induced immunomodulatory leukocytes-such as interleukin-10 (IL-10) producing CD14+ monocytes15 by performing magnetic bead surface marker selection of cell populations of interest prior to or after co-culture as appropriate. Our protocol describes the basic assay of assessing the immunomodulatory effects of MSCs on effector leukocytes (flow chart shown in Figure 1) and a variation on this basic assay for evaluation of MSC-induced leukocyte immunomodulation on allogeneic CD4+ effector T lymphocytes (flow chart shown in Figure 4).

<table border="0" cellpadding="0" cellspacing="0" width="1205">
	<tbody>
		<tr height="20">
			<td height="20" style="height:20px;width:276px;">Ficoll-Paque PLUS</td>
			<td style="width:259px;">GE Healthcare</td>
			<td style="width:121px;">71-7167-00 AG</td>
			<td style="width:549px;">Density grandient for isolation of peripheral blood mononuclear cells (PBMCs)</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:276px;">Vibrant CFDA-SE Cell Tracer Kit (CFSE)</td>
			<td style="width:259px;">Life Technologies</td>
			<td style="width:121px;">V12883</td>
			<td>Cellular label for detection of cell division</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:276px;">Phytoagglutinin (PHA)</td>
			<td style="width:259px;">Sigma</td>
			<td>L8902</td>
			<td>Activation of human PBMCs</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:276px;">Dynabeads Human T-Activator CD3/28</td>
			<td style="width:259px;">Life Technologies</td>
			<td style="width:121px;">111.32D</td>
			<td style="width:549px;">Activation of human T lymphocytes, e.g. CD4+ T cells, CD8+ T cells,etc.</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;">autoMACS&#8482; Separator</td>
			<td>Miltenyi Biotec</td>
			<td style="width:121px;">autoMACS&#8482; Separator</td>
			<td>Magnetic based cell separator</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">autoMACS&#174; Columns</td>
			<td>Miltenyi Biotec</td>
			<td>130-021-101</td>
			<td>separation columns</td>
		</tr>
		<tr height="25">
			<td height="25" style="height:25px;width:276px;">CD14 microbeads, human&#160;</td>
			<td>Miltenyi Biotec</td>
			<td>130-050-201</td>
			<td style="width:549px;">For positive selection of CD14+ human monocytes and macrophages from PBMCs</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:276px;">CD4 microbeads, human&#160;</td>
			<td>Miltenyi Biotec</td>
			<td style="width:121px;">130-045-101</td>
			<td style="width:549px;">For positive selection of CD4+ human T lymphocytes from PBMCs</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:276px;">RPMI 1640 Medium</td>
			<td style="width:259px;">Life Technologies</td>
			<td style="width:121px;">11875</td>
			<td>Human PBMC/leukocyte culture medium</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:276px;">DMEM, Low glucose, pyruvate</td>
			<td style="width:259px;">Life Technologies</td>
			<td style="width:121px;">11885</td>
			<td style="width:549px;">Human mesenchymal stem cell (MSC) culture medium</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:276px;">L-glutamine</td>
			<td style="width:259px;">Life Technologies</td>
			<td>25030-081</td>
			<td>Supplementation for MSC complete medium</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:276px;">Penicillin/Streptomycin</td>
			<td style="width:259px;">Life Technologies</td>
			<td>15070-063</td>
			<td>Supplementation for PBMC/leukocyte and MSC complete medium</td>
		</tr>
		<tr height="80">
			<td height="80" style="height:80px;width:276px;">Fetal bovine serum (FBS)</td>
			<td style="width:259px;">1) Hyclone, for MSC culture&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; 2) Life Technologies, for all other cells (i.e. PBMCs, specific leukocyte populations)</td>
			<td style="width:121px;">1) SH30070.03M 2) 10091-148</td>
			<td>Pre-test lots for support of MSC in vitro culture</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:276px;">24-well cell culture plate</td>
			<td style="width:259px;">Corning</td>
			<td>COR3524</td>
			<td>Co-culture plate</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:276px;">50 mL centrifuge tube</td>
			<td style="width:259px;">Corning</td>
			<td style="width:121px;">430291</td>
			<td>Isolation PBMCs from whole blood by Ficoll-Paque PLUS</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:276px;">15 mL centrifuge tube&#160;</td>
			<td style="width:259px;">Corning</td>
			<td style="width:121px;">430766</td>
			<td>Collection of the labeled and unlabeled cell fractions</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Round-bottom tubes</td>
			<td style="width:259px;">BD Falcon&#160;</td>
			<td style="width:121px;">352008</td>
			<td>Collection of cells for flow cytometric analysis</td>
		</tr>
	</tbody>
</table>

assessment of the immunomodulatory properties of human mesenchymal stem cells (mscs)

The immunomodulatory properties of multilineage human mesenchymal stem cells (MSCs) appear to be highly relevant for clinical use towards a wide-range of immune-related diseases. Mechanisms involved are increasingly being elucidated and in this article, we describe the basic experiment to assess MSC immunomodulation by assaying for suppression of effector leukocyte proliferation. Representing activation, leukocyte proliferation can be assessed by a number of techniques, and we describe in this protocol the use of the fluorescent cellular dye carboxyfluorescein succinimidyl ester (CFSE) to label leukocytes with subsequent flow cytometric analyses. This technique can not only assess proliferation without radioactivity, but also the number of cell divisions that have occurred as well as allowing for identification of the specific population of proliferating cells and intracellular cytokine/factor expression. Moreover, the assay can be tailored to evaluate specific populations of effector leukocytes by magnetic bead surface marker selection of single peripheral blood mononuclear cell populations prior to co-culture with MSCs. The flexibility of this co-culture assay is useful for investigating cellular interactions between MSCs and leukocytes.

Figure 1 denotes the overall schema of the experiment, and Figure 2 demonstrates the appearance of the various cell culture conditions as visualized by phase-contrast inverted microscopy. MSCs are adherent cells with a fibroblastic, spindle-shaped morphology, whereas PBMCs and leukocytes are small round non-adherent cells. These two morphologically different cell types can be clearly seen in the co-culture. At the end of the assay, when the PBMCs (or leuckotyes) are aspirated for flow cytometric analyses, ev...

Watch this Scientific Journal Video about Assessment of the Immunomodulatory Properties of Human Mesenchymal Stem Cells MSCs at JoVE.com

Assessment of the Immunomodulatory Properties of Human Mesenchymal Stem Cells MSCs

The immunomodulatory properties of human mesenchymal stem cells (MSC) appear increasingly relevant for clinical application. Using a co-culture system of MSCs and peripheral blood leukocytes pre-stained with the fluorescent dye carboxyfluorescein succinimidyl ester (CFSE), we describe the in vitro assessment of MSC immunomodulation on effector leukocyte proliferation and specific subpopulations.

Assessment of the Immunomodulatory Properties of Human Mesenchymal Stem Cells (MSCs)

The immunomodulatory properties of multilineage human mesenchymal stem cells (MSCs) appear to be highly relevant for clinical use towards a wide-range of ...

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