This work was funded in part by grant P40RR17447 from the National Institute of Health and award RP150637 from the Cancer Prevention and Research Institute of Texas. We would like to thank Dr. Darwin J. Prockop for his support on the project.

<ol>
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The International Society for Cellular Therapy position statement.</a> Cytotherapy. 8 (4), 315-317 (2006).</li><li>Fontaine, M. J., Shih, H., Schafer, R., Pittenger, M. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Unraveling+the+Mesenchymal+Stromal+Cells'+Paracrine+Immunomodulatory+Effects.">Unraveling the Mesenchymal Stromal Cells' Paracrine Immunomodulatory Effects.</a> Transfus.Med.Rev. 30 (1), 37-43 (2016).</li><li>Nemeth, K., 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=Bone+marrow+stromal+cells+attenuate+sepsis+via+prostaglandin+E(2)-dependent+reprogramming+of+host+macrophages+to+increase+their+interleukin-10+production.">Bone marrow stromal cells attenuate sepsis via prostaglandin E(2)-dependent reprogramming of host macrophages to increase their interleukin-10 production.</a> Nat.Med. 15 (1), 42-49 (2009).</li><li>Prockop, D. 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The authors declare they have no competing financial interests.

The optimal MSC for use in some research and clinical applications should be highly activated to maximize their benefit, and preferentially prepared under chemically defined XF conditions to minimize the delivery of potential antigens from xenogeneic medium components such as FBS. In the protocols described here, we have shown methods to 1) activate MSCs in 3D culture by formation of spheroids, 2) achieve the 3D activation of MSCs under XF conditions, 3) evaluate the activation levels of spheroid MSCs in regards to their...

Mesenchymal stem/stromal cells (MSCs) have shown great potential for various regenerative medicine approaches. MSCs were initially isolated as a stromal component of bone marrow but have since been obtained from numerous other adult tissues, including adipose tissue1,2,3. Interestingly, the main isolation method embraces the remarkable property of MSCs to adhere tightly onto tissue culture plastic in the presence of fetal bovine serum (FBS). Whilst this traditional isolation technique permits easy and rapid expansion of MSCs in two-dimensional (2D) culture, it is also very artificial and disregards significance of the native three-dimensional (3D) environment leading to potential loss of important cellular characteristics4,5,6. Therefore, the study of MSCs in 3D cultures, which are more physiological than traditional 2D cultures, has emerged in search for &#34;lost/diminished&#34; MSC characteristics. Furthermore, great interest has risen to identify xeno-free (XF) chemically defined conditions for MSC culture and activation, and thus make the cells more amenable for clinical applications.
Many studies have been published demonstrating the 3D culture of MSCs both in biomaterials and as spherical aggregates or spheroids. MSCs in biomaterials were initially designed for tissue engineering approaches to replace damaged tissues with cell-seeded scaffolds, whereas spheroid cultures of MSCs were seen as a way to understand MSC behavior in vivo after administration of the cells for therapies in pre-clinical or clinical trials4,5,7. Interestingly, MSCs form spheroids spontaneously when adherence to tissue culture plastic is not permitted8,9,10. Traditionally, cell aggregation was facilitated by spinner flask methods or liquid overlay techniques, methods used initially in cancer biology in efforts to try to mimic the tumor microenvironment. More recently, additional methods have surfaced that demonstrate cell aggregation in culture dishes pre-coated with specific chemicals to prevent cell-to-plastic adhesion4,5,6. One of the simplest and most economical methods to generate MSC spheroids is to culture them in hanging drops, a technique that was often used to produce embryoid bodies from embryonic stem cells. With hanging drop culture technique, cell adherence to the tissue culture plastic is prevented by suspending the cells in a drop of medium on the underside of a tissue culture dish lid and allowing gravity to facilitate cell aggregation in the apex of the drop. The spheroid size can be readily manipulated by changing the cell concentration or the drop volume, making hanging drop cultures particularly easy to control.
Early studies on the 3D culture of MSCs demonstrated radical differences in the characteristics of the cells in 3D compared to their 2D counterparts6,8,9. At the same time, reports demonstrated that the beneficial effects of MSCs in vivo relied on their ability to become activated by micro-environmental cues and, in response, to produce anti-inflammatory and immunomodulatory factors11. Interestingly, many of these factors such as prostaglandin E2 (PGE2), tumor necrosis factor-stimulated gene 6 (TSG6), and hepatocyte growth factor (HGF) were produced in much larger quantities by MSC spheroids than traditional 2D MSCs paving the way for the idea of using 3D cultures to activate the cells8,12,13. Moreover, gene activation in 3D cultures appeared to recapitulate mechanisms, at least in part, of cell activation after injection into mice12. By activating MSCs prior to their use in experiments, effects of the cells could be prolonged and more prominent as the traditional MSC effect in vivo is often delayed and transient, and can be described as &#34;hit and run&#34;. During the past several years, important functional studies using MSC spheroids have demonstrated that they can suppress inflammatory responses and modulate immunity in vivo by influencing effector cells such as macrophages, dendritic cells, neutrophils, and T cells making spheroids an attractive form of primed MSCs2,3. In addition, production of anti-cancer molecules, such as interleukin-24 (IL-24) and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), are increased in 3D cultures of MSCs relative to monolayer MSCs, a phenomenon that could be exploited for targeted cancer therapies8,10,14.
As the traditional MSC culture required not only the use of tissue culture plastic but also FBS, another hurdle to make MSC spheroids more amenable for clinical use had to be overcome. To tackle this hurdle, we recently showed formation of MSC spheroids under specific chemically defined XF conditions and established that the resulting MSC spheroids were activated to produce the same anti-inflammatory and anti-cancer molecules as the spheroids generated in conditions with FBS14. Here, these findings are presented in several detailed protocols that demonstrate the generation of pre-activated MSCs in 3D cultures using XF media. In addition, protocols are presented that describe effective ways to assess the activation levels of the MSCs in regards to their anti-inflammatory, immunomodulatory and anti-cancer effects, together with a practical method to deliver the intact spheroids into mice.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>MEM-&#945; (minimal essential medium alpha)</td>
			<td>ThermoFisher/Gibco</td>
			<td>12561049; 12561056; 12561072</td>
			<td>minimal essential medium for preparation of MSC growth medium (CCM)</td>
		</tr>
		<tr>
			<td>FBS (fetal bovine serum), premium select</td>
			<td>Atlanta Biologicals</td>
			<td>S11595; S11510; S11550; S11595-24</td>
			<td>component of complete culture media for all types of cells</td>
		</tr>
		<tr>
			<td>L-glutamine</td>
			<td>ThermoFisher/Gibco</td>
			<td>25030081; 25030149; 25030164</td>
			<td>component of complete culture media for all types of cells</td>
		</tr>
		<tr>
			<td>Penicillin/Streptomycin</td>
			<td>ThermoFisher/Gibco</td>
			<td>15070063</td>
			<td>component of complete culture media for all types of cells</td>
		</tr>
		<tr>
			<td>Sterilization Filter Units, 0.22 &#181;m PES membrane</td>
			<td>MilliporeSigma</td>
			<td>SCGPU01RE; SCGPU02RE; SCGPU05RE; SCGPU10RE; SCGPU11RE</td>
			<td>media sterilization</td>
		</tr>
		<tr>
			<td>150 mm cell culture dish</td>
			<td>Nunc</td>
			<td>D8554&#160;SIGMA</td>
			<td>cell culture</td>
		</tr>
		<tr>
			<td>Thermo Forma water-jacketed CO2 humidified incubator</td>
			<td>Thermo Fisher</td>
			<td>Model 3110</td>
			<td>incubation of cultured cells</td>
		</tr>
		<tr>
			<td>Early passage MCSs</td>
			<td>Center for the preparation and Distribution of Adult Stem Cells at The Texas A&#38;M Health Science Center College of Medicine Institute for Regenerative Medicine at Scott &#38; White</td>
			<td>NA</td>
			<td>preparation of 2D and 3D cultures of MSCs</td>
		</tr>
		<tr>
			<td>water bath</td>
			<td>VWR</td>
			<td>89501-468</td>
			<td>warming media to 37 &#176;C</td>
		</tr>
		<tr>
			<td>Pipettes</td>
			<td>Eppendorf</td>
			<td>492000904</td>
			<td>manual liquid handling</td>
		</tr>
		<tr>
			<td>Pipete-Aid</td>
			<td>Drummond Scientific Company</td>
			<td>4-000-300</td>
			<td>handling sereological pipetes</td>
		</tr>
		<tr>
			<td>Costar sterile serological pipet (5, 10, 25 and 50 ml)</td>
			<td>Corning</td>
			<td>4487; 4101; 4251; 4490</td>
			<td>liquid handling</td>
		</tr>
		<tr>
			<td>PBS (phosphate buffered saline), pH 7.4</td>
			<td>ThermoFisher/Gibco</td>
			<td>10010023; 10010072; 10010031; 10010049</td>
			<td>cell culture processing</td>
		</tr>
		<tr>
			<td>0.25% trypsin/EDTA solution</td>
			<td>ThermoFisher/Gibco</td>
			<td>25200056; 25200072; 25200114</td>
			<td>lifting adherent cells and dispersing cell aggregates</td>
		</tr>
		<tr>
			<td>15 ml conical tube</td>
			<td>Corning/BD Falcon</td>
			<td>352097</td>
			<td>cell centrifugation</td>
		</tr>
		<tr>
			<td>50 ml conical tube</td>
			<td>Corning/BD Falcon</td>
			<td>352098</td>
			<td>cell centrifugation</td>
		</tr>
		<tr>
			<td>Eppendor refrigerated centrifuge</td>
			<td>Eppendorf/Fisher Scientific</td>
			<td>Model 5810R</td>
			<td>cell centrifugation</td>
		</tr>
		<tr>
			<td>hemocytometer</td>
			<td>Fisher Scientific</td>
			<td>26716</td>
			<td>cell counting</td>
		</tr>
		<tr>
			<td>trypan blue</td>
			<td>Sigma-Aldrich</td>
			<td>T8154 SIGMA</td>
			<td>dead cell exclusion during cell counting in hemacytometer</td>
		</tr>
		<tr>
			<td>Defined xenofree MSC medium-1 (XFM-1)</td>
			<td>ThermoFisher/Gibco</td>
			<td>A1067501</td>
			<td>Xeno-free media specifically formulated for the growth and expansion of human mesenchymal stem cells</td>
		</tr>
		<tr>
			<td>Defined xenofree MSC medium-2 (XFM-2)</td>
			<td>Stem Cell Technologies</td>
			<td>5420</td>
			<td>Defined, xeno-free medium for human mesenchymal stem cells</td>
		</tr>
		<tr>
			<td>HSA (Human serum albumin)</td>
			<td>Gemini</td>
			<td>800-120</td>
			<td>Component of xeno-free MSC media</td>
		</tr>
		<tr>
			<td>rHSA (recombinant Human serum albumin)</td>
			<td>Sigma-Aldrich</td>
			<td>A9731&#160;SIGMA</td>
			<td>Component of xeno-free MSC media</td>
		</tr>
		<tr>
			<td>8-channel pipette, 10&#8239;&#8211;&#8239;100&#8239;&#181;L</td>
			<td>Eppendorf</td>
			<td>022453904</td>
			<td>preparation of hanging drops</td>
		</tr>
		<tr>
			<td>Total RNA isolation Mini Kit</td>
			<td>Qiagen</td>
			<td>74104</td>
			<td>Total RNA extraction</td>
		</tr>
		<tr>
			<td>Qiashredder</td>
			<td>Qiagen</td>
			<td>79654</td>
			<td>Sample homogenization prior to total RNA extraction</td>
		</tr>
		<tr>
			<td>RNAse-free DNase Set&#160;</td>
			<td>Qiagen</td>
			<td>79254</td>
			<td>On-column DNA elimination during total RNA extraction</td>
		</tr>
		<tr>
			<td>&#946;-mercaptoethanol&#160;</td>
			<td>Sigma-Aldrich</td>
			<td>M6250&#160;ALDRICH</td>
			<td>inhibition of RNAses in RLT buffer</td>
		</tr>
		<tr>
			<td>Vortex</td>
			<td>VWR</td>
			<td>97043-562</td>
			<td>mixing sample</td>
		</tr>
		<tr>
			<td>Spectrophotometer</td>
			<td>Biorad</td>
			<td>NA</td>
			<td>RNA concentration and quality</td>
		</tr>
		<tr>
			<td>High capacity cDNA Reverse Transcription Kit</td>
			<td>ThermoFisher/Applied Biosystems</td>
			<td>4368814</td>
			<td>transcription of total RNA into cDNA</td>
		</tr>
		<tr>
			<td>Gene Expression Assays</td>
			<td>ThermoFisher/Applied Biosystems</td>
			<td>varies</td>
			<td>primer/probe combination for real-time PCR</td>
		</tr>
		<tr>
			<td>Fast Universal PCR Master Mix</td>
			<td>ThermoFisher/Applied Biosystems</td>
			<td>4352042; 4364103; 4366073; 4367846</td>
			<td>master mix for real-time PCR reaction</td>
		</tr>
		<tr>
			<td>Real-time PCR system (ABI Prism 7900 HT Sequence Detection System)</td>
			<td>ABI Prizm</td>
			<td>NA</td>
			<td>real-time PCR</td>
		</tr>
		<tr>
			<td>1.5 ml centrifuge tube</td>
			<td>Eppendorf</td>
			<td>22364111</td>
			<td>cell centrifugation, sample collection and storage</td>
		</tr>
		<tr>
			<td>(-80&#176;C) freezer</td>
			<td>Thermo Fisher</td>
			<td>Model Thermo Forma 8695</td>
			<td>sample storage</td>
		</tr>
		<tr>
			<td>PGE2 (Prostaglandin E2) ELISA Kit</td>
			<td>R&#38;D Systems</td>
			<td>KGE004B</td>
			<td>estimation of cytokine concentration in the sample</td>
		</tr>
		<tr>
			<td>DMEM (Dulbecco&#8217;s modified Eagle medium)</td>
			<td>ThermoFisher/Gibco</td>
			<td>10566-016; 10566-024;10566-032</td>
			<td>macrophage culture media</td>
		</tr>
		<tr>
			<td>J774 mouse macrophages</td>
			<td>ATCC</td>
			<td>TIB-67</td>
			<td>mouse macrophage cell line</td>
		</tr>
		<tr>
			<td>12-well plate</td>
			<td>Corning</td>
			<td>3513</td>
			<td>in-vitro macrophage stimulation</td>
		</tr>
		<tr>
			<td>LPS (lipopolysaccharide)</td>
			<td>Sigma-aldrich</td>
			<td>L4130</td>
			<td>in vitro macrophage stimulation</td>
		</tr>
		<tr>
			<td>Mouse TNF-a ELISA kit</td>
			<td>R&#38;D Systems</td>
			<td>MTA00B</td>
			<td>estimation of cytokine concentration in the sample</td>
		</tr>
		<tr>
			<td>Mouse IL-10 (interleukin 10) ELISA kit</td>
			<td>R&#38;D Systems</td>
			<td>M1000B</td>
			<td>estimation of cytokine concentration in the sample</td>
		</tr>
		<tr>
			<td>RPMI-1640 medium</td>
			<td>ThermoFisher/Gibco</td>
			<td>11875-085</td>
			<td>splenocyte culture media</td>
		</tr>
		<tr>
			<td>BALB/c mice</td>
			<td>The Jackson Laboratory</td>
			<td>651</td>
			<td>in vivo spheroid delivery; splenocyte preparation</td>
		</tr>
		<tr>
			<td>Anti-Mouse CD3e Functional Grade Purified</td>
			<td>eBioscience</td>
			<td>145-2C11</td>
			<td>In vitro splenocyte stimulation</td>
		</tr>
		<tr>
			<td>70 &#956;m strainer&#160;</td>
			<td>Corning</td>
			<td>352350</td>
			<td>Splenocyte preparation</td>
		</tr>
		<tr>
			<td>Red blood cell lysis solution (1x)</td>
			<td>Affymetrix eBioscience</td>
			<td>00-4333</td>
			<td>removal of red blood cells during splenocyte isolation</td>
		</tr>
		<tr>
			<td>Mouse IFN-y (interferon gamma) ELISA kit</td>
			<td>R&#38;D Systems</td>
			<td>MIF 00</td>
			<td>estimation of cytokine concentration in the sample</td>
		</tr>
		<tr>
			<td>LNCaP prostate cancer cells&#160;</td>
			<td>ATCC</td>
			<td>CRL-1740</td>
			<td>study the effect of 3D MSCs on cancer cell lines in vitro</td>
		</tr>
		<tr>
			<td>DNA-based cell proliferation assay kit</td>
			<td>ThermoFisher</td>
			<td>C7026</td>
			<td>cell number measurement based on DNA content</td>
		</tr>
		<tr>
			<td>NaCl</td>
			<td>Sigma-Aldrich</td>
			<td>S5150</td>
			<td>component of lysis reagent</td>
		</tr>
		<tr>
			<td>EDTA (ethylenediaminetetraacetic acid)</td>
			<td>ThermoFisher</td>
			<td>FERR1021</td>
			<td>calcium chelator, component of lysis reagent</td>
		</tr>
		<tr>
			<td>Rnase A</td>
			<td>Qiagen</td>
			<td>19101</td>
			<td>RNA degradation for measurement of DNA</td>
		</tr>
		<tr>
			<td>Filter-based multi-mode microplate reader</td>
			<td>BMG Technology</td>
			<td>NA</td>
			<td>Microplate assays (ELISA, cell quantification, e.t.c.)</td>
		</tr>
		<tr>
			<td>HBSS (Hanks balanced salt solution), no calcium, no magnesium, no phenol red</td>
			<td>ThermoFisher/Gibco</td>
			<td>14175079</td>
			<td>resupsension of MSC spheroids prior to in vivo injections</td>
		</tr>
		<tr>
			<td>Isoflurane</td>
			<td>MWI Vet Supply</td>
			<td>502017</td>
			<td>Anesthesia for in vivo injections</td>
		</tr>
		<tr>
			<td>Oxygen, compressed gas</td>
			<td>Praxair</td>
			<td>NA</td>
			<td>For use with isoflurane</td>
		</tr>
		<tr>
			<td>Thermo Forma BSL-2 cabinet</td>
			<td>Thermo Fisher</td>
			<td>Model 1385</td>
			<td>Sterile cell culture</td>
		</tr>
		<tr>
			<td>Safety I.V. catheter/needle stiletto, 20G, 1 inch</td>
			<td>Terumo</td>
			<td>SR*FNP2025</td>
			<td>Delivery of shperoids into peritoneal cavity</td>
		</tr>
		<tr>
			<td>Sterile micropipette tips</td>
			<td>Eppendorf</td>
			<td>varies</td>
			<td>liquid/cells handling</td>
		</tr>
	</tbody>
</table>

production and administration of therapeutic mesenchymal stem/stromal cell (msc) spheroids primed in 3-d cultures under xeno-free conditions

Mesenchymal stem/stromal cells (MSCs) hold great promise in bioengineering and regenerative medicine. MSCs can be isolated from multiple adult tissues via their strong adherence to tissue culture plastic and then further expanded in vitro, most commonly using fetal bovine serum (FBS). Since FBS can cause MSCs to become immunogenic, its presence in MSC cultures limits both clinical and experimental applications of the cells. Therefore, studies employing chemically defined xeno-free (XF) media for MSC cultures are extremely valuable. Many beneficial effects of MSCs have been attributed to their ability to regulate inflammation and immunity, mainly through secretion of immunomodulatory factors such as tumor necrosis factor-stimulated gene 6 (TSG6) and prostaglandin E2 (PGE2). However, MSCs require activation to produce these factors and since the effect of MSCs is often transient, great interest has emerged to discover ways of pre-activating the cells prior to their use, thus eliminating the lag time for activation in vivo. Here we present protocols to efficiently activate or prime MSCs in three-dimensional (3D) cultures under chemically defined XF conditions and to administer these pre-activated MSCs in vivo. Specifically, we first describe methods to generate spherical MSC micro-tissues or &#39;spheroids&#39; in hanging drops using XF medium and demonstrate how the spheres and conditioned medium (CM) can be harvested for various applications. Second, we describe gene expression screens and in vitro functional assays to rapidly assess the level of MSC activation in spheroids, emphasizing the anti-inflammatory and anti-cancer potential of the cells. Third, we describe a novel method to inject intact MSC spheroids into the mouse peritoneal cavity for in vivo efficacy testing. Overall, the protocols herein overcome major challenges of obtaining pre-activated MSCs under chemically defined XF conditions and provide a flexible system to administer MSC spheroids for therapies.

In the current work, hanging drop cultures were employed to generate compact spherical micro-tissues or &#39;spheroids&#39; of activated MSCs under XF conditions. The investigational roadmap in Figure 1 depicts that MSCs are encouraged to self-assemble into spheroids when suspended in hanging drops for 72 hr, after which the spheroids, or the CM loaded with sphere-derived therapeutic factors, can be collected and potentially utilized in both research and clinical applicat...

Watch this Scientific Journal Video about Production and Administration of Therapeutic Mesenchymal Stem/Stromal Cell MSC Spheroids Primed in 3-D Cultures Under Xeno-free Conditions at JoVE.com

Production and Administration of Therapeutic Mesenchymal Stem/Stromal Cell MSC Spheroids Primed in 3-D Cultures Under Xeno-free Conditions

The therapeutic potential of mesenchymal stem/stromal cells (MSCs) is well-documented, however the best method of preparing the cells for patients remains controversial. Herein, we communicate protocols to efficiently generate and administer therapeutic spherical aggregates or 'spheroids' of MSCs primed under xeno-free conditions for experimental and clinical applications.

Production and Administration of Therapeutic Mesenchymal Stem/Stromal Cell (MSC) Spheroids Primed in 3-D Cultures Under Xeno-free Conditions

Mesenchymal stem/stromal cells (MSCs) hold great promise in bioengineering and regenerative medicine. MSCs can be isolated from multiple adult tissues via ...

production-administration-therapeutic-mesenchymal-stemstromal-cell

Research

JoVE Journal

Developmental Biology

11.8K Views.  University of Mary Hardin-Baylor. The therapeutic potential of mesenchymal stem/stromal cells (MSCs) is well-documented, however the best method of preparing the cells for patients remains controversial. Herein, we communicate protocols to efficiently generate and administer therapeutic spherical aggregates or 'spheroids' of MSCs primed under xeno-free conditions for experimental and clinical applications.

Video: Production and Administration of Therapeutic Mesenchymal Stem/Stromal Cell MSC Spheroids Primed in 3-D Cultures Under Xeno-free Conditions

Generation of Genetically Modified Organotypic Skin Cultures Using Devitalized Human Dermis

Organotypic cultures allow the reconstitution of a 3D environment critical for cell-cell contact and cell-matrix interactions which mimics the function and physiology of their in vivo tissue counterparts. This is exemplified by organotypic skin cultures which faithfully recapitulates the epidermal differentiation and stratification program. Primary human epidermal keratinocytes are genetically manipulable through retroviruses where genes can be easily overexpressed or knocked down. These genetically modified keratinocytes can then be used to regenerate human epidermis in organotypic skin cultures providing a powerful model to study genetic pathways impacting epidermal growth, differentiation, and disease progression. The protocols presented here describe methods to prepare devitalized human dermis as well as to genetically manipulate primary human keratinocytes in order to generate organotypic skin cultures. Regenerated human skin can be used in downstream applications such as gene expression profiling, immunostaining, and chromatin immunoprecipitations followed by high throughput sequencing. Thus, generation of these genetically modified organotypic skin cultures will allow the determination of genes that are critical for maintaining skin homeostasis.

The goal of this paper is to provide a comprehensive and detailed protocol on how to generate genetically modified human organotypic skin from epidermal keratinocytes and devitalized human dermis.

Organotypic cultures allow the reconstitution of a 3D environment critical for cell-cell contact and cell-matrix interactions which mimics the function ...

Isolation and Expansion of Mesenchymal Stem/Stromal Cells Derived from Human Placenta Tissue

Mesenchymal stem/stromal cells (MSC) are promising candidates for use in cell-based therapies. In most cases, therapeutic response appears to be cell-dose dependent. Human term placenta is rich in MSC and is a physically large tissue that is generally discarded following birth. Placenta is an ideal starting material for the large-scale manufacture of multiple cell doses of allogeneic MSC. The placenta is a fetomaternal organ from which either fetal or maternal tissue can be isolated. This article describes the placental anatomy and procedure to dissect apart the decidua (maternal), chorionic villi (fetal), and chorionic plate (fetal) tissue. The protocol then outlines how to isolate MSC from each dissected tissue region, and provides representative analysis of expanded MSC derived from the respective tissue types. These methods are intended for pre-clinical MSC isolation, but have also been adapted for clinical manufacture of placental MSC for human therapeutic use.

Herein we describe methods for the dissection of fetal and maternal tissues from human term placenta, followed by isolation and expansion of mesenchymal stem/stromal cells (MSC) from these tissues.

Mesenchymal stem/stromal cells (MSC) are promising candidates for use in cell-based therapies. In most cases, therapeutic response appears to be cell-dose ...

Rearing the Fruit Fly Drosophila melanogaster Under Axenic and Gnotobiotic Conditions

The influence of microbes on myriad animal traits and behaviors has been increasingly recognized in recent years. The fruit fly Drosophila melanogaster is a model for understanding microbial interactions with animal hosts, facilitated by approaches to rear large sample sizes of Drosophila under microorganism-free (axenic) conditions, or with defined microbial communities (gnotobiotic). This work outlines a method for collection of Drosophila embryos, hypochlorite dechorionation and sterilization, and transfer to sterile diet. Sterilized embryos are transferred to sterile diet in 50 ml centrifuge tubes, and developing larvae and adults remain free of any exogenous microbes until the vials are opened. Alternatively, flies with a defined microbiota can be reared by inoculating sterile diet and embryos with microbial species of interest. We describe the introduction of 4 bacterial species to establish a representative gnotobiotic microbiota in Drosophila. Finally, we describe approaches for confirming bacterial community composition, including testing if axenic Drosophila remain bacteria-free into adulthood.

Rearing the Fruit Fly Drosophila melanogaster Under Axenic and Gnotobiotic Conditions

A method for rearing Drosophila melanogaster under axenic and gnotobiotic conditions is presented. Fly embryos are dechorionated in sodium hypochlorite, transferred aseptically to sterile diet, and reared in closed containers. Inoculating diet and embryos with bacteria leads to gnotobiotic associations, and bacterial presence is confirmed by plating whole-body Drosophila homogenates.

The influence of microbes on myriad animal traits and behaviors has been increasingly recognized in recent years. The fruit fly Drosophila melanogaster is ...

Reprogramming Primary Amniotic Fluid and Membrane Cells to Pluripotency in Xeno-free Conditions

Autologous cell-based therapies got a step closer to reality with the introduction of induced pluripotent stem cells. Fetal stem cells, such as amniotic fluid and membrane mesenchymal stem cells, represent a unique type of undifferentiated cells with promise in tissue engineering and for reprogramming into iPSC for future pediatric interventions and stem cell banking. The protocol presented here describes an optimized procedure for extracting and culturing primary amniotic fluid and membrane mesenchymal stem cells and generating episomal induced pluripotent stem cells from these cells in fully chemically defined culture conditions utilizing human recombinant vitronectin and the E8 medium. Characterization of the new lines by applying stringent methods &#8211; flow cytometry, confocal imaging, teratoma formation and transcriptional profiling &#8211; is also described. The newly generated lines express markers of embryonic stem cells &#8211; Oct3/4A, Nanog, Sox2, TRA-1-60, TRA-1-81, SSEA-4 &#8211; while being negative for the SSEA-1 marker. The stem cell lines form teratomas in scid-beige mice in 6-8 weeks and the teratomas contain tissues representative of all three germ layers. Transcriptional profiling of the lines by submitting global expression microarray data to a bioinformatic pluripotency assessment algorithm deemed all lines pluripotent and therefore, this approach is an attractive alternative to animal testing. The new iPSC lines can readily be used in downstream experiments involving the optimization of differentiation and tissue engineering.

This protocol describes the reprogramming of primary amniotic fluid and membrane mesenchymal stem cells into induced pluripotent stem cells using a non-integrating episomal approach in fully chemically defined conditions. Procedures of extraction, culture, reprogramming, and characterization of the resulting induced pluripotent stem cells by stringent methods are detailed.

Autologous cell-based therapies got a step closer to reality with the introduction of induced pluripotent stem cells. Fetal stem cells, such as amniotic ...

Live Cell Imaging of Chromosome Segregation During Mitosis

Chromosomes must be reliably and uniformly segregated into daughter cells during mitotic cell division. Fidelity of chromosomal segregation is controlled by multiple mechanisms that include the Spindle Assembly Checkpoint (SAC). The SAC is part of a complex feedback system that is responsible for prevention of a cell progress through mitosis unless all chromosomal kinetochores have attached to spindle microtubules. Chromosomal lagging and abnormal chromosome segregation is an indicator of dysfunctional cell cycle control checkpoints and can be used to measure the genomic stability of dividing cells. Deregulation of the SAC can result in the transformation of a normal cell into a malignant cell through the accumulation of errors during chromosomal segregation. Implementation of the SAC and the formation of the kinetochore complex are tightly regulated by interactions between kinases and phosphatase such as Protein Phosphatase 2A (PP2A). This protocol describes live cell imaging of lagging chromosomes in mouse embryonic fibroblasts isolated from mice that had a knockout of the PP2A-B56&#947; regulatory subunit. This method overcomes the shortcomings of other cell cycle control imaging techniques such as flow cytometry or immunocytochemistry that only provide a snapshot of a cell cytokinesis status, instead of a dynamic spatiotemporal visualization of chromosomes during mitosis.

This protocol describes an easy and convenient method to label and visualize live chromosomes in mitotic cells using Histone2B-GFP BacMam 2.0 label and a spinning disc confocal microscopy system.

Chromosomes must be reliably and uniformly segregated into daughter cells during mitotic cell division. Fidelity of chromosomal segregation is controlled ...

Defined Xeno-free and Feeder-free Culture Conditions for the Generation of Human iPSC-derived Retinal Cell Models

The production of specialized cells from pluripotent stem cells provides a powerful tool to develop new approaches for regenerative medicine. The use of human-induced pluripotent stem cells (iPSCs) is particularly attractive for neurodegenerative disease studies, including retinal dystrophies, where iPSC-derived retinal cell models mark a major step forward to understand and fight blindness. In this paper, we describe a simple and scalable protocol to generate, mature, and cryopreserve retinal organoids. Based on medium changing, the main advantage of this method is to avoid multiple and time-consuming steps commonly required in a guided differentiation of iPSCs. Mimicking the early phases of retinal development by successive changes of defined media on adherent human iPSC cultures, this protocol allows the simultaneous generation of self-forming neuroretinal structures and retinal pigmented epithelial (RPE) cells in a reproducible and efficient manner in 4 weeks. These structures containing retinal progenitor cells (RPCs) can be easily isolated for further maturation in a floating culture condition enabling the differentiation of RPCs into the seven retinal cell types present in the adult human retina. Additionally, we describe quick methods for the cryopreservation of retinal organoids and RPE cells for long-term storage. Combined together, the methods described here will be useful to produce and bank human iPSC-derived retinal cells or tissues for both basic and clinical research.

The production of specialized retinal cells from pluripotent stem cells is a turning point in the development of stem cell-based therapy for retinal diseases. The present paper describes a simple method for an efficient generation of retinal organoids and retinal pigmented epithelium for basic, translational, and clinical research.

The production of specialized cells from pluripotent stem cells provides a powerful tool to develop new approaches for regenerative medicine. The use of ...

Induction of Endothelial Differentiation in Cardiac Progenitor Cells Under Low Serum Conditions

Cardiac progenitor cells (CPCs) may have therapeutic potential for cardiac regeneration after injury. In the adult mammalian heart, intrinsic CPCs are extremely scarce, but expanded CPCs could be useful for cell therapy. A prerequisite for their use is their ability to differentiate in a controlled manner into the various cardiac lineages using defined and efficient protocols. In addition, upon in vitro expansion, CPCs isolated from patients or preclinical disease models may offer fruitful research tools for the investigation of disease mechanisms.
Current studies use different markers to identify CPCs. However, not all of them are expressed in humans, which limits the translational impact of some preclinical studies. Differentiation protocols that are applicable irrespective of the isolation technique and marker expression will allow for the standardized expansion and priming of CPCs for cell therapy purpose. Here we describe that the priming of CPCs under a low fetal bovine serum (FBS) concentration and low cell density conditions facilitates the endothelial differentiation of CPCs. Using two different subpopulations of mouse and rat CPCs, we show that laminin is a more suitable substrate than fibronectin for this purpose under the following protocol: after culturing for 2 - 3 days in medium including supplements that maintain multipotency and with 3.5% FBS, CPCs are seeded on laminin at &#60;60% confluence and cultured in supplement-free medium with low concentrations of FBS (0.1%) for 20 - 24 hours before differentiation in endothelial differentiation medium. Because CPCs are a heterogeneous population, serum concentrations and incubation times may need to be adjusted depending on the properties of the respective CPC subpopulation. Considering this, the technique can be applied to other types of CPCs as well and provides a useful method to investigate the potential and mechanisms of differentiation and how they are affected by disease when using CPCs isolated from respective disease models.

This protocol describes an endothelial differentiation technique for cardiac progenitor cells. It particularly focuses on how serum concentration and cell-seeding density affect the endothelial differentiation potential.

Cardiac progenitor cells (CPCs) may have therapeutic potential for cardiac regeneration after injury. In the adult mammalian heart, intrinsic CPCs are ...

Controlled Cortical Impact Model of Mouse Brain Injury with Therapeutic Transplantation of Human Induced Pluripotent Stem Cell-Derived Neural Cells

Traumatic brain injury (TBI) is a leading cause of morbidity and mortality worldwide. Disease pathology due to TBI progresses from the primary mechanical insult to secondary injury processes, including apoptosis and inflammation. Animal modeling has been valuable in the search to unravel injury mechanisms and evaluate potential neuroprotective therapies. This protocol describes the controlled cortical impact (CCI) model of focal, open-head TBI. Specifically, parameters for producing a mild unilateral cortical injury are described. Behavioral consequences of CCI are analyzed using the adhesive tape removal test of bilateral sensorimotor integration. Regarding experimental therapy for TBI pathology, this protocol also illustrates a process for transplanting cultured cells into the brain. Neural cell cultures derived from human induced pluripotent stem cells (hiPSCs) were chosen for their potential to show superior functional restoration in human TBI patients. Chronic survival of hiPSCs in the host mouse brain tissue is detected using a modified DAB immunohistochemical process.

This protocol demonstrates methodologies for a mouse model of open-skull traumatic brain injury and transplantation of cultured human induced pluripotent stem cell-derived cells into the injury site. Behavioral and histologic tests of outcomes from these procedures are also described in brief.

Traumatic brain injury (TBI) is a leading cause of morbidity and mortality worldwide. Disease pathology due to TBI progresses from the primary mechanical ...

Hemogenic Endothelium Differentiation from Human Pluripotent Stem Cells in A Feeder- and Xeno-free Defined Condition

Deriving functional hematopoietic stem and progenitor cells (HSPCs) from human pluripotent stem cells (PSCs) have been an elusive goal for autologous transplants to treat hematological and malignant disorders. Hemogenic endothelium (HE) is an amenable platform to produce functional HSPCs by transcription factors or to induce lymphocytes in a robust manner. However, current methods to derive HE are either costly or variable in yield. In this protocol, we established a cost-effective and precise method to derive HE within 4 days in a feeder- and xeno-free defined condition. The resultant HE underwent an endothelial-to-hematopoietic transition and produced CD34+CD45+ clonogenic hematopoietic progenitors. The potential capacity of our platform for generating functional HSPCs will have broad applications in disease modeling and screening for therapeutic compounds.

Here, we present a protocol to precisely form hemogenic endothelium from human pluripotent stem cells in a feeder- and xeno-free condition. This method will have broad applications in disease modeling and screening for therapeutic compounds.

Deriving functional hematopoietic stem and progenitor cells (HSPCs) from human pluripotent stem cells (PSCs) have been an elusive goal for autologous ...

Formation of Human Periodontal Ligament Cell Spheroids on Chitosan Films

Periodontal ligament (PDL) cells hold great promise for periodontal tissue regeneration. Conventionally, PDL cells are cultured on two-dimensional (2D) substrates such as tissue culture polystyrene (TCPS). However, characteristic changes of PDL cells have been observed during in vitro culture. This phenomenon is probably because the 2D TCPS differs from the in vivo three-dimensional (3D) microenvironment. Compared to cells cultured on 2D substrates, cells grown in a 3D microenvironment exhibit more similarities to in vivo cells. Therefore, 3D cell culture models provide a promising alternative for conventional 2D monolayer cell culture. To improve conventional PDL cell culture models, we have recently developed a 3D cell culture method, which is based on spheroid formation of PDL cells on chitosan films. Here, we present detailed cell spheroid culture protocols based on chitosan films. The 3D culture system of PDL cellular spheroids overcome some of the limitations related to conventional 2D monolayer cell culture, and thus may be suitable for producing PDL cells with an enhanced therapeutic efficacy for future periodontal tissue regeneration.

Here, we present protocols of culturing human periodontal ligament (PDL) cell spheroids by chitosan films. The culture of three-dimensional (3D) cellular spheroids provides an alternative to conventional tissue culture polystyrene (TCPS) culture system.

Periodontal ligament (PDL) cells hold great promise for periodontal tissue regeneration. Conventionally, PDL cells are cultured on two-dimensional (2D) ...