Name: uptake of new lipid-coated nanoparticles containing falcarindiol by human mesenchymal stem cells
Uploaded: 2019-02-09T14:00:00
Description: Watch this Scientific Journal Video about Uptake of New Lipid-coated Nanoparticles Containing Falcarindiol by Human Mesenchymal Stem Cells at JoVE.com

The authors thank Dr. Moustapha Kassem (Odense University Hospital, Denmark) for the human mesenchymal stem cells. The authors thank the Danish Medical Bioimaging Center for access to their microscopes. The authors thank the Carlsberg and Villum foundations for financial support (to E.A.C.). The authors acknowledge the financial support provided by the Niels Bohr Professorship award from the Danish National Research Foundation.

1. Nanoparticle synthesis by rapid solvent shifting technique
<ol>
	<li>Set up the following for the nanoparticles&#39; preparation: a block heater/sample concentrator, a desiccator, a digital dispensing system with a 1 mL glass syringe, a 12 mL glass vial, a magnetic stirrer, a magnetic flea (15 mm x 4.5 mm, in a cylindrical shape with polytetrafluoroethylene [PTFE] coating) inside the glass vial, and a rotatory evaporator.</li>
	<li>Dispense 2.4 mL of 250 &#181;M falcarindiol stock dissolved in 70% EtOH water mixture...

<ol>
	<li>Firestone, R. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Low-Density+Lipoprotein+as+a+Vehicle+for+Targeting+Antitumor+Compounds+to+Cancer+Cells.">Low-Density Lipoprotein as a Vehicle for Targeting Antitumor Compounds to Cancer Cells.</a> Bioconjugate Chemistry. 5 (2), 105-113 (1994).</li><li>Beloribi-Djefaflia, S., Vasseur, S., Guillaumond, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Lipid+metabolic+reprogramming+in+cancer+cells.">Lipid metabolic reprogramming in cancer cells.</a> Oncogenesis. 5 (1), 189 (2016).</li><li>Xin, Y., Yin, M., Zhao, L., Meng, F., Luo, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Recent+progress+on+nanoparticle-based+drug+delivery+systems+for+cancer+therapy.">Recent progress on nanoparticle-based drug delivery systems for cancer therapy.</a> Cancer Biology &amp; Medicine. 14 (3), 228 (2017).</li><li>Merriel, S. W. D., Carroll, R., Hamilton, F., Hamilton, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Association+between+unexplained+hypoalbuminaemia+and+new+cancer+diagnoses+in+UK+primary+care+patients.">Association between unexplained hypoalbuminaemia and new cancer diagnoses in UK primary care patients.</a> Family Practice. 33 (5), 449-452 (2016).</li><li>Yue, 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=Cholesteryl+ester+accumulation+induced+by+PTEN+loss+and+PI3K/AKT+activation+underlies+human+prostate+cancer+aggressiveness.">Cholesteryl ester accumulation induced by PTEN loss and PI3K/AKT activation underlies human prostate cancer aggressiveness.</a> Cell Metabolism. 19 (3), 393-406 (2014).</li><li>dos Santos, R., 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=LDL-cholesterol+signaling+induces+breast+cancer+proliferation+and+invasion.">LDL-cholesterol signaling induces breast cancer proliferation and invasion.</a> Lipids in Health and Disease. 13 (16), (2014).</li><li>Gallagher, E. J., 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=Elevated+tumor+LDLR+expression+accelerates+LDL+cholesterol-mediated+breast+cancer+growth+in+mouse+models+of+hyperlipidemia+HHS+Public+Access.">Elevated tumor LDLR expression accelerates LDL cholesterol-mediated breast cancer growth in mouse models of hyperlipidemia HHS Public Access.</a> Oncogene. 36 (46), 6462-6471 (2017).</li><li>Needham, D., 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=Bottom+up+design+of+nanoparticles+for+anti-cancer+diapeutics:+"put+the+drug+in+the+cancer's+food".">Bottom up design of nanoparticles for anti-cancer diapeutics: "put the drug in the cancer's food".</a> Journal of Drug Targeting. 24 (9), 836-856 (2016).</li><li>Lacko, A. G., Mconnathy, W. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Targeted+cancer+chemotherapy+using+synthetic+nanoparticles.">Targeted cancer chemotherapy using synthetic nanoparticles.</a> United States Patent Application Publication. , (2009).</li><li>Nikanjam, M., Gibbs, A. R., Hunt, C. A., Budinger, T. F., Forte, T. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Synthetic+nano-LDL+with+paclitaxel+oleate+as+a+targeted+drug+delivery+vehicle+for+glioblastoma+multiforme.">Synthetic nano-LDL with paclitaxel oleate as a targeted drug delivery vehicle for glioblastoma multiforme.</a> Journal of Controlled Release. 124 (3), 163-171 (2007).</li><li>Teerlink, T., Scheffer, P. G., Bakker, S. J. L., Heine, R. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Combined+data+from+LDL+composition+and+size+measurement+are+compatible+with+a+discoid+particle+shape.">Combined data from LDL composition and size measurement are compatible with a discoid particle shape.</a> Journal of Lipid Research. 45 (5), 954-966 (2004).</li><li>Schweizer, M. T., 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=A+phase+I+study+of+niclosamide+in+combination+with+enzalutamide+in+men+with+castration-resistant+prostate+cancer.">A phase I study of niclosamide in combination with enzalutamide in men with castration-resistant prostate cancer.</a> PLoS ONE. 13 (8), 0202709 (2018).</li><li>Allen, T. M., Hansen, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pharmacokinetics+of+stealth+versus+conventional+liposomes:+effect+of+dose.">Pharmacokinetics of stealth versus conventional liposomes: effect of dose.</a> Biochimica et Biophysica Acta (BBA) - Biomembranes. 1068 (2), 133-141 (1991).</li><li>Maeda, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Enhanced+Permeability+and+Retention+(EPR)+Effect+in+Tumor+Vasculature:+The+Key+Role+of+Tumor-Selective+Macromolecular+Drug+Targeting.">The Enhanced Permeability and Retention (EPR) Effect in Tumor Vasculature: The Key Role of Tumor-Selective Macromolecular Drug Targeting.</a> Advances in Enzyme Regulation. 41 (1), 189-207 (2001).</li><li>Wong, A. D., Ye, M., Ulmschneider, M. B., Searson, P. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Quantitative+Analysis+of+the+Enhanced+Permeation+and+Retention+(EPR)+Effect.">Quantitative Analysis of the Enhanced Permeation and Retention (EPR) Effect.</a> PLoS ONE. 10 (5), 0123461 (2015).</li><li>Khodabandehloo, H., Zahednasab, H., Hafez, A. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nanocarriers+Usage+for+Drug+Delivery+in+Cancer+Therapy.">Nanocarriers Usage for Drug Delivery in Cancer Therapy.</a> Iranian Journal of Psychiatry and Behavioral Sciences. 9 (2), (2016).</li><li>Kobaek-Larsen, M., El-Houri, R. B., Christensen, L. P., Al-Najami, I., Frett&#233;, X., Baatrup, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dietary+polyacetylenes,+falcarinol+and+falcarindiol,+isolated+from+carrots+prevents+the+formation+of+neoplastic+lesions+in+the+colon+of+azoxymethane-induced+rats.">Dietary polyacetylenes, falcarinol and falcarindiol, isolated from carrots prevents the formation of neoplastic lesions in the colon of azoxymethane-induced rats.</a> Food &amp; Function. 8, 964-974 (2017).</li><li>Hervella, P., Parra, E., Needham, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Encapsulation+and+retention+of+chelated-copper+inside+hydrophobic+nanoparticles:+Liquid+cored+nanoparticles+show+better+retention+than+a+solid+core+formulation.">Encapsulation and retention of chelated-copper inside hydrophobic nanoparticles: Liquid cored nanoparticles show better retention than a solid core formulation.</a> European Journal of Pharmaceutics and Biopharmaceutics. 102, 64-76 (2016).</li><li>Hervella, P., 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=Chelation,+formulation,+encapsulation,+retention,+and+in+vivo+biodistribution+of+hydrophobic+nanoparticles+labelled+with+57Co-porphyrin:+Octyl+Amine+ensures+stable+chelation+of+cobalt+in+Liquid+Nanoparticles+that+accumulate+in+tumors.">Chelation, formulation, encapsulation, retention, and in vivo biodistribution of hydrophobic nanoparticles labelled with 57Co-porphyrin: Octyl Amine ensures stable chelation of cobalt in Liquid Nanoparticles that accumulate in tumors.</a> Journal of Controlled Release. , (2018).</li><li>Zhigaltsev, I. V., 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=Bottom-up+design+and+synthesis+of+limit+size+lipid+nanoparticle+systems+with+aqueous+and+triglyceride+cores+using+millisecond+microfluidic+mixing.">Bottom-up design and synthesis of limit size lipid nanoparticle systems with aqueous and triglyceride cores using millisecond microfluidic mixing.</a> Langmuir. 28 (7), 3633-3640 (2012).</li><li>Aubry, J., Ganachaud, F., Cohen Addad, J. -. P., Cabane, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nanoprecipitation+of+Polymethylmethacrylate+by+Solvent+Shifting:1+Boundaries.">Nanoprecipitation of Polymethylmethacrylate by Solvent Shifting:1 Boundaries.</a> Langmuir. 25 (4), 1970-1979 (2009).</li><li>Karnik, R., 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=Microfluidic+Platform+for+Controlled+Synthesis+of+Polymeric+Nanoparticles.">Microfluidic Platform for Controlled Synthesis of Polymeric Nanoparticles.</a> Nano Letters. 8 (9), 2906-2912 (2008).</li><li>Gaumet, M., Vargas, A., Gurny, R., Delie, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nanoparticles+for+drug+delivery:+The+need+for+precision+in+reporting+particle+size+parameters.">Nanoparticles for drug delivery: The need for precision in reporting particle size parameters.</a> European Journal of Pharmaceutics and Biopharmaceutics. 69 (1), 1-9 (2018).</li><li>Christensen, L. P., Brandt, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bioactive+polyacetylenes+in+food+plants+of+the+Apiaceae+family:+Occurrence,+bioactivity+and+analysis.">Bioactive polyacetylenes in food plants of the Apiaceae family: Occurrence, bioactivity and analysis.</a> Journal of Pharmaceutical and Biomedical Analysis. 41 (3), 683-693 (2016).</li><li>Kobaek-Larsen, M., Christensen, L. P., Vach, W., Ritskes-Hoitinga, J., Brandt, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Inhibitory+Effects+of+Feeding+with+Carrots+or+(-)+-Falcarinol+on+Development+of+Azoxymethane-Induced+Preneoplastic+Lesions+in+the+Rat+Colon.">Inhibitory Effects of Feeding with Carrots or (-) -Falcarinol on Development of Azoxymethane-Induced Preneoplastic Lesions in the Rat Colon.</a> Journal of Agricultural and Food Chemistry. 53, 1823-1827 (2005).</li><li>Jin, H. R., 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=The+antitumor+natural+compound+falcarindiol+promotes+cancer+cell+death+by+inducing+endoplasmic+reticulum+stress.">The antitumor natural compound falcarindiol promotes cancer cell death by inducing endoplasmic reticulum stress.</a> CellDeath &amp; Disease. 3, 1-9 (2012).</li><li>Walke, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Physico-Chemical+Parameters+of+Nanoparticles+that+Govern+Prodrug+Design+and+Application+in+Anticancer+Nanomedicine+in+Physics,+Chemistry,+Pharmacy.">Physico-Chemical Parameters of Nanoparticles that Govern Prodrug Design and Application in Anticancer Nanomedicine in Physics, Chemistry, Pharmacy.</a> University of Southern Denmark (SDU). , (2018).</li><li>Walke, P. B., Hervella, P., Needham, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Lipid-Coated+Stealth+Nanoparticles+of+Novel+Hydrophobic+Prodrug,+Niclosamide+Stearate,+as+Cancer+Therapeutic:+Formulation+and+Physico-Chemical+Characterization+of+Nanoparticles.">Lipid-Coated Stealth Nanoparticles of Novel Hydrophobic Prodrug, Niclosamide Stearate, as Cancer Therapeutic: Formulation and Physico-Chemical Characterization of Nanoparticles.</a> 6th International Pharmaceutical Federation Pharmaceutical Sciences World Congress. , (2017).</li></ol>

A detailed protocol for fabricating lipid-coated nanoparticles for drug delivery with the simple, fast, reproducible, and scalable rapid injection method of solvent shifting was followed27,28 and is presented in this paper, as applied to falcarindiol. By controlling the speed of the injection of the organic phase into aqueous phase and by using coating lipids at appropriate concentrations to coat the falcarindiol core, particle in the sub-100 nm range could be ob...

Lipid-coated nanoparticles are seeing an increased interest regarding their function as drug delivery systems for cancer therapy1. Cancers have an altered lipid-metabolic reprogramming2 and an increased need for cholesterol to proliferate3. They overexpress LDLs1 and take in more LDLs than normal cells, to the extent that a cancer patient&#39;s LDL count can even go down4. LDL uptake promotes aggressive phenotypes5 resulting in proliferation and invasion in breast cancer6. An abundance of LDL receptors (LDLRs) is a prognostic indicator of metastatic potential7. Inspired by the LDL and its uptake by cancer cells, a new strategy has been called: Make the drug look like the cancer&#39;s food8. Thus, these new nanoparticle drug delivery designs8,9,10&#160;have been inspired by the core- and lipid-stabilized design of the natural LDLs11&#160;as a mechanism for delivering anticancer drugs to cancer cells. This passive targeting delivery system supports the encapsulating of, especially, hydrophobic drugs, which are usually given in oral dosage form but provide only a small amount of the drugs to the bloodstream, so limiting their expected efficacy12. As with the stealth liposomes13, a polyethylene glycol (PEG) coating helps to reduce any immunologic response and extends the circulation in the bloodstream for optimum tumor uptake by the purported enhanced permeation and retention (EPR) effect14,15. However, in addition to, in some instances, instability in the circulation and undesirable distribution in the system16, some obstacles remain unsolved, such as how and to what extent such nanoparticles are taken in by cells and what is their intracellular fate. It is here that this paper addresses the nanoparticle uptake of a particular hydrophobic anticancer drug falcarindiol, using confocal and epifluorescence imaging techniques.
The aim of the study is to fabricate lipid-coated nanoparticles of falcarindiol and to study their intracellular uptake in hMSCs.&#160;Thereby, potentially stabilizing its administration, overcoming the challenges associated with the delivery, and improving the bioavailability. Thus assessing a new delivery system for this anticancer drug. Previously, falcarindiol has been administrated orally via a high concentration purified falcarindiol as a food supplement17. However, there is need for a more structured approach to deliver this promising drug. Therefore, falcarindiol nanoparticles, with a phospholipid and cholesterol encapsulating monolayer with the purified drug constituting the core of the particle, were designed. The rapid injection method of solvent shifting, as recently developed by Needham&#160;et al.8, is used in this study to encapsulate the polyacetylene falcarindiol.
The method has previously been used for the fabrication of lipid nanoparticles to encapsulate diagnostic imaging agents18,19, as well as test molecules (triolein)27 and drugs (orlistat, niclosamide stearate)8,27,28. It is a relatively simple technique when carried out with the right molecules. It forms nanosized particles, at the limit of their critical nucleation (~20 nm diameter), of highly insoluble hydrophobic solutes dissolved in a polar solvent. The solvent exchange is&#160;accomplished by a rapid injection of the organic solution into an excess of antisolvent (usually, an aqueous phase in a 1:9 organic:aqueous volume ratio)20,21.
The compositional design of the nanoparticles give rise to multiple advantages. The DSPC:Chol components provide a very tight, almost impermeable, biocompatible, and biodegradable monolayer.The PEG provides a sterically stabilizing interface which acts as a shield from opsonization by the immune system, slowing any uptake by the reticuloendothelial system (liver and spleen) and protecting against the mononuclear phagocyte system, preventing their retention and degradation by the immune system, and hence, increasing their circulation half-time in blood22. This allows the particles to circulate until they extravasate at diseased sites, such as tumors, where the vascular system is leaky, allowing EPR-effect to give rise to passive accumulation of the particles. Additionally, the lipid coat&#160;allows one to have better control over the nanoparticles&#39; size by kinetically trapping the core at its critical nucleus dimension27,28. Lipids induce various surface properties (including peptide targeting, which was not yet available for this project), a pure drug core, and a low polydispersity22,27,28. The method used for particle size analysis is DLS, a technique that allows researchers to measure the size of a large number of particles at the same time. However, this method can bias the measurements to bigger sizes, if the nanoparticles are not monodispersed23. This issue is assessed with the lipid coat as well. More details of these fundamental designs and the quantification of all characteristics are given in other publications27,28.
The drug encapsulated in the nanoparticles is falcarindiol, a dietary polyacetylene found in plants from the Apiaceae family. It is a secondary metabolite from the aliphatic C17polyacetylenes type that has been found to display health-promoting effects, including anti-inflammatory activity, antibacterial effects, and cytotoxicity against a wide range of cancer cell lines. Its high reactivity is related to its ability to interact with different biomolecules, acting as a very reactive alkylating agent against mercapto and amino groups24. Falcarindiol has previously been shown to reduce the number of neoplastic lesions in the colon17,25, although the biological mechanisms are still unknown. However, it is thought that it interacts with biomolecules such as NF-&#954;B, COX1, COX-2, and cytokines, inhibiting their tumor progression and cell proliferation processes, leading to arresting the cell cycle, endoplasmic reticulum (ER) stress, and apoptosis17,26 in cancer cells. Falcarindiol is used in this study as an example anticancer drug due to&#160;its anticancer potential and mechanism are being studied currently, and because it shows promising anticancer effects. The cellular uptake of the nanoparticles is tested in hMSCs and imaged using epifluorescence and confocal microscopy. This cell type was chosen due to its large size, making them ideal for microscopy.

<table border="0" cellpadding="0" cellspacing="0" style="width:965px;" width="966">
	<colgroup>
		<col />
		<col />
		<col />
		<col />
	</colgroup>
	<tbody>
		<tr height="42">
			<td height="42" style="height:42px;width:255px;">12 mL Screw Neck Vial (Clear glass, 15-425 thread, 66 X 18.5 mm)</td>
			<td style="width:384px;">Microlab Aarhus A/S</td>
			<td style="width:160px;">ML 33154LP</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:255px;">6 well plates</td>
			<td>Greiner Bio One International GmbH</td>
			<td style="width:160px;">657160</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:255px;">Absolute Ethanol</td>
			<td>EMD Millipore (VWR)</td>
			<td>EM8.18760.1000</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:255px;">Chloroform</td>
			<td>Rathburn Chemicals Ltd.</td>
			<td>RH1009</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:255px;">Cholesterol</td>
			<td>Avanti Polar Lipids, Inc.</td>
			<td>700000P</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:255px;">Confocal Microscope</td>
			<td style="width:384px;">Zeiss LSM510</td>
			<td style="width:160px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:255px;">Cover Slips thickness #1.5</td>
			<td>Paul Marienfeld GmbH &#38; Co</td>
			<td>117650</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:255px;">Desiccator</td>
			<td style="width:384px;">Self-build</td>
			<td style="width:160px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:255px;">DiI</td>
			<td>Invitrogen</td>
			<td style="width:160px;">D282</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:255px;">DLS</td>
			<td style="width:384px;">Beckman Coulter</td>
			<td style="width:160px;">DelsaMAXpro 3167-DMP</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:255px;">DSPC (Chloroform stock)</td>
			<td>Avanti Polar Lipids, Inc.</td>
			<td>850365C&#160;</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:255px;">DSPE PEG 2000 (Chloroform stock)</td>
			<td>Avanti Polar Lipids, Inc.</td>
			<td>880120C</td>
			<td></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:255px;">eVol XR</td>
			<td>SGE analytical science, Trajan Scientific Australia Pty Ltd.</td>
			<td>2910200</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:255px;">Fetal Bovine serum</td>
			<td>Gibco</td>
			<td style="width:160px;">10270-106</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:255px;">Fluorescence Miccroscope</td>
			<td style="width:384px;">Olymous IX81</td>
			<td style="width:160px;"></td>
			<td>With Manual TIRF and Andor iXon EMCCD</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:255px;">Incubator</td>
			<td style="width:384px;">Panasonic&#160;</td>
			<td style="width:160px;">MCO-18AC</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:255px;">Magnetic flea</td>
			<td>VWR Chemicals</td>
			<td>15 x 4.5 mm</td>
			<td>Cylindrical shape with PTFE coating</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:255px;">Magnetic stirrer</td>
			<td>IKA</td>
			<td style="width:160px;">RT-10</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Minimum Essential Media</td>
			<td>Gibco</td>
			<td style="width:160px;">32561-029</td>
			<td></td>
		</tr>
		<tr height="26">
			<td height="26" style="height:26px;width:255px;">PBS tablets for cell culture</td>
			<td style="width:384px;">VWR Chemicals</td>
			<td>97062-732</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:255px;">Pen/strep</td>
			<td>VWR Chemicals</td>
			<td>97063-708</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:255px;">Phosphate Buffer Saline (PBS, pH 7.4)</td>
			<td>Thermo Fisher</td>
			<td>10010031</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:255px;">Rotary Evaporator</td>
			<td>Rotavapor, B&#252;chi Labortechnik AG</td>
			<td style="width:160px;">R-210</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:255px;">Sample concentrator&#160;</td>
			<td>Stuart, Cole-Parmer Instrument Company, LLC</td>
			<td style="width:160px;">SBHCONC/1</td>
			<td></td>
		</tr>
	</tbody>
</table>

uptake of new lipid-coated nanoparticles containing falcarindiol by human mesenchymal stem cells

Nanoparticles are the focus of an increased interest in drug delivery systems for cancer therapy. Lipid-coated nanoparticles are inspired in structure and size by low-density lipoproteins (LDLs) because cancer cells have an increased need for cholesterol to proliferate, and this has been exploited as a mechanism for delivering anticancer drugs to cancer cells. Moreover, depending on drug chemistry, encapsulating the drug can be advantageous to avoid degradation of the drug during circulation in vivo. Therefore, in this&#160;study, this design is used to fabricate lipid-coated nanoparticles of the anticancer drug falcarindiol, providing a potential new delivery system of falcarindiol in order to stabilize its chemical structure against degradation and improve its uptake by tumors. Falcarindiol nanoparticles, with a phospholipid and cholesterol monolayer encapsulating the purified drug core of the particle, were designed. The lipid monolayer coating consists of 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC), cholesterol (Chol), and 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(polyethylene glycol)-2000] (DSPE PEG 2000) along with the fluorescent label DiI (molar ratios of 43:50:5:2). The nanoparticles are fabricated using the rapid injection method, which is a fast and simple technique to precipitate nanoparticles by good-solvent for anti-solvent exchange. It consists of a rapid injection of an ethanol solution containing the nanoparticle components into an aqueous phase. The size of the fluorescent nanoparticles is measured using dynamic light scattering (DLS) at 74.1 &#177; 6.7 nm. The uptake of the nanoparticles is tested in human mesenchymal stem cells (hMSCs) and imaged using fluorescence and confocal microscopy. The uptake of the nanoparticles is observed in hMSCs, suggesting the potential for such a stable drug delivery system for falcarindiol.

Two different types of nanoparticles were fabricated, namely pure falcarindiol nanoparticles and lipid-coated falcarindiol nanoparticles. Various concentrations of lipids and cholesterol were tested. As shown in Table 1, uncoated nanoparticles formed in water and measured in PBS had a diameter of 71 &#177; 20.3 nm with a polydispersity index (PDI) of 0.571. Those parameters were measured on a DLS analyzer. The lipid-coated nanoparticles of falcarindiol used in the experim...

Watch this Scientific Journal Video about Uptake of New Lipid-coated Nanoparticles Containing Falcarindiol by Human Mesenchymal Stem Cells at JoVE.com

Uptake of New Lipid-coated Nanoparticles Containing Falcarindiol by Human Mesenchymal Stem Cells

This article describes the encapsulation of falcarindiol in lipid-coated 74 nm nanoparticles. The cellular uptake of the nanoparticles&#160;by human stem cells into lipid droplets is monitored by fluorescent and confocal imaging. Nanoparticles are fabricated by the rapid injection method of solvent shifting, and their size is measured with the dynamic light scattering technique.

Nanoparticles are the focus of an increased interest in drug delivery systems for cancer therapy. Lipid-coated nanoparticles are inspired in structure and ...

The fabrication of lipid-coated nanoparticles with the rapid injection method provides a stable drug delivery system for cancer therapy. This technique is a simple, fast, scalable, and reproducible technique for nanoparticle fabrication that encapsulates hydrophobic drugs. This technique is applicable for fabricating diagnostic and therapeutic nanoparticles from hydrphobic materials that can be effectively used in several disease conditions.This fabrication technique, along with DLS, can be used to study the nucleation and growth of hydrophobic materials, such as lipids, proteins, and polymers. Knowing the physical chemical properties of your drug substance is critical before fabricating the nanoparticles. Also, be sure to use the correct concentrations of coating lipids.Visual demonstration of this method is critical to show the simplicity of the fabrication technique and to show the successful delivery of the drug as nanoparticles to the cells. Precaution needs to be taken when working with chloroform and formaldehyde, and working under a fume hood is required. To begin, dispense 2.4 milliliters of 250 micromolar falcarindiol stock solution dissolved in 70%ethanol in a scintillation vial.Using a sample concentrator, evaporate the liquid fraction for approximately four hours to obtain dry falcarindiol. Using the sample concentrator, deliver gas over the sample at room temperature to concentrate the sample. Once dried, add the components shown here to the scintillation vial in a fume hood, making sure to clean the syringe with chloroform after adding each component to avoid cross contamination.Then immediately close the vials containing the lipids so that the solvent does not evaporate and thereby modify the concentration. Wrap the vial with aluminum foil to protect DiI from light and leave the sample overnight in the desiccator to evaporate the chloroform. The next day, dissolve the desiccated sample in absolute ethanol to make a final volume of 1.2 milliliters.This solution represents the organic phase. Take a 12 milliliter glass vial and fill it with nine milliliters of purified water. Then add a magnetic flea into the vial containing nine milliliters of water.Place the vial on a magnetic stirrer and stir at 500 rpm. Next attach a one milliliter glass syringe to the dispensing system and slowly pull chloroform in and out of the glass syringe at least 10 times. Dispense the chloroform into its waste collector each time.Cleaning the syringe with chloroform helps to avoid any contamination. Now prime the syringe with ethanol. Priming replaces the old solvent as well as removes any air bubbles.Using the syringe, aspirate one milliliter of the organic phase, and insert the syringe into the glass vial up to the middle of the nine milliliter water mark. Maintain it steady in the middle of the vial, and inject the solution at 833 microliters per second by pressing the dispense button on the dispensing system. This generates 10 microliters of 50 micromolar lipid coated nanoparticles of falcarindiol in 10%ethanol.This injection speed has been found to achieve finest nanoparticles with narrow particle size distribution. While injecting, it is important to make sure that the needle is inserted in the center, steady and straight. Immediately after the injection, remove the vial from the stirrer and transfer the sample to a 50 milliliter round bottom flask.Attack the flask to the rotary evaporator, and evaporate one milliliter of the organic solvent at room temperature. Be cautious to avoid excess bubble formation. Transfer the nanoparticle suspension from the flask to another 12 milliliter glass vial.Ensure that the volume is nine milliliters, and then split the sample in two 12 milliliter glass vials. Then add 0.5 milliliters of ultra pure water in one of the vials and 0.5 milliliter of 10X phosphate buffered saline in the other vial. Turn on the digital light scattering instrument, and set the desired temperature to 20 degrees Celsius until it stabilizes.Then set the instrument parameters as shown here. Fill the plastic cuvette with one milliliter of nanoparticle suspension, and start the measurement. Report the measured size depending on the solvent that was used.Seed approximately 50, 000 cells on sterile 1.5 cover slips placed in six-well plate to obtain a cell density of approximately 30%Then add culture medium in order to have a final volume of three milliliters in each well. Incubate the cells for 24 hours under standard culture conditions. The next day, add three microliters of the nanoparticle solution for a final falcarindiol concentration of five micromolar.Then return the cells to the incubator for 24 hours. After 24 hours of treatment, wash the cells twice with PBS, and then fix them in 4%formaldehyde for 10 minutes at room temperature. Following fixation, permeabilize the cells with 0.1%Triton X-100 for 30 minutes.Then wash them twice with PBS, and stain them with 250 microliters of 300 nanomolar DAPI for five minutes, protected from light. Place the cover slip onto a slide using a drop of PBS. Turn to a 150x subjective, and transfer the slide to the stage of a wide-field fluorescence microscope equipped with an electron multiplied CCD camera.Image cells using the GFP-LP channel. Additionally, verify the uptake of the nanoparticles into the cells by taking confocal microscopy images using a 63x oil objective with a numerical aperture of 1.4. Image DiI using an argon laser at 514 nanometers and DAPI using a two-photon laser at 780 nanometers.Uncoated nanoparticles of falcarindiol formed in water and measured in PBS showed high polydispersity, with PD index of 0.571. This value indicates broad and nonuniform distribution of particle sizes. In contrast, lipid coated nanoparticles of falcarindiol fabricated in this video were of 74.1 nanometers with a polydispersity index of 0.182, indicated a relatively monodisperse and uniform distribution of particle sizes.As a first observation of the nanoparticles inside the cells, epifluorescence microscopy images were acquired after 24 hours of treatment. The nanoparticles were visualized as white, bright dots, and it could be hypothesized that nanoparticles were located inside the cells surrounding the nucleus. To verify that falcarindiol nanoparticles had entered the cells, confocal microscopy was performed on the cells as well.A large number of nanoparticles are shown here, scattered in the cytoplasm in every cell. These results show that nanoparticles act as a stable drug delivery system for falcarindiol. While attempting this procedure, it's important to inject the solution at the right injection speed, keeping the seeding steady, in the center, to ensure proper mixing.This procedure can be used for any hydrophobic drug to formulate therapeutic nanoparticles or for imaging agents to formulate diagnostic nanoparticles that can be used in various disease conditions, such as cancer. This technique enabled more research to be conducted on the mechanism by which the nanoparticles get taken up by cells, as well as its live cell imaging and on studying the anticancer effect of the drug.

uptake-new-lipid-coated-nanoparticles-containing-falcarindiol-human

Research

JoVE Journal

Bioengineering

Alginate Microcapsule as a 3D Platform for Propagation and Differentiation of Human Embryonic Stem Cells (hESC) to Different Lineages

Human embryonic stem cells (hESC) are emerging as an attractive alternative source for cell replacement therapy since they can be expanded in culture indefinitely and differentiated to any cell types in the body. Various types of biomaterials have also been used in stem cell cultures to provide a microenvironment mimicking the stem cell niche1-3. The latter is important for promoting cell-to-cell interaction, cell proliferation, and differentiation into specific lineages as well as tissue organization by providing a three-dimensional (3D) environment4 such as encapsulation. The principle of cell encapsulation involves entrapment of living cells within the confines of semi-permeable membranes in 3D cultures2. These membranes allow for the exchange of nutrients, oxygen and stimuli across the membranes, whereas antibodies and immune cells from the host that are larger than the capsule pore size are excluded5. Here, we present an approach to culture and differentiate hESC DA neurons in a 3D microenvironment using alginate microcapsules. We have modified the culture conditions2 to enhance the viability of encapsulated hESC. We have previously shown that the addition of p160-Rho-associated coiled-coil kinase (ROCK) inhibitor, Y-27632 and human fetal fibroblast-conditioned serum replacement medium (hFF-CM) to the 3D platform significantly enhanced the viability of encapsulated hESC in which the cells expressed definitive endoderm marker genes1. We have now used this 3D platform for the propagation of hESC and efficient differentiation to DA neurons. Protein and gene expression analyses after the final stage of DA neuronal differentiation showed an increased expression of tyrosine hydroxylase (TH), a marker for DA neurons, &gt;100 folds after 2 weeks. We hypothesized that our 3D platform using alginate microcapsules may be useful to study the proliferation and directed differentiation of hESC to various lineages. This 3D system also allows the separation of feeder cells from hESC during the process of differentiation and also has potential for immune-isolation during transplantation in the future.

Alginate Microcapsule as a 3D Platform for Propagation and Differentiation of Human Embryonic Stem Cells hESC to Different Lineages

We have optimized a microencapsulation technique as an effective 3D platform for propagation and differentiation of embryonic stem cells to endoderm and dopaminergic (DA) neurons. It also provides an opportunity for immune-isolation of cells from the host during transplantation. This platform can be adapted for other cell types.

Human embryonic stem cells (hESC) are emerging as an attractive alternative source for cell replacement therapy since they can be expanded in culture ...

Development, Expansion, and In vivo Monitoring of Human NK Cells from Human Embryonic Stem Cells (hESCs) and Induced Pluripotent Stem Cells (iPSCs)

We present a method for deriving natural killer (NK) cells from undifferentiated hESCs and iPSCs using a feeder-free approach. This method gives rise to high levels of NK cells after 4 weeks culture and can undergo further 2-log expansion with artificial antigen presenting cells. hESC- and iPSC-derived NK cells developed in this system have a mature phenotype and function. The production of large numbers of genetically modifiable NK cells is applicable for both basic mechanistic as well as anti-tumor studies. Expression of firefly luciferase in hESC-derived NK cells allows a non-invasive approach to follow NK cell engraftment, distribution, and function. We also describe a dual-imaging scheme that allows separate monitoring of two different cell populations to more distinctly characterize their interactions in vivo. This method of derivation, expansion, and dual in vivo imaging provides a reliable approach for producing NK cells and their evaluation which is necessary to improve current NK cell adoptive therapies.

Development, Expansion, and In vivo Monitoring of Human NK Cells from Human Embryonic Stem Cells hESCs and Induced Pluripotent Stem Cells iPSCs

This protocol describes the development, expansion, and in vivo imaging of NK cells derived from hESCs and iPSCs.

We present a method for deriving natural killer (NK) cells from undifferentiated hESCs and iPSCs using a feeder-free approach. This method gives rise to ...

Programming Stem Cells for Therapeutic Angiogenesis Using Biodegradable Polymeric Nanoparticles

Controlled vascular growth is critical for successful tissue regeneration and wound healing, as well as for treating ischemic diseases such as stroke, heart attack or peripheral arterial diseases. Direct delivery of angiogenic growth factors has the potential to stimulate new blood vessel growth, but is often associated with limitations such as lack of targeting and short half-life in vivo. Gene therapy offers an alternative approach by delivering genes encoding angiogenic factors, but often requires using virus, and is limited by safety concerns. Here we describe a recently developed strategy for stimulating vascular growth by programming stem cells to overexpress angiogenic factors in situ using biodegradable polymeric nanoparticles. Specifically our strategy utilized stem cells as delivery vehicles by taking advantage of their ability to migrate toward ischemic tissues in vivo. Using the optimized polymeric vectors, adipose-derived stem cells were modified to overexpress an angiogenic gene encoding vascular endothelial growth factor (VEGF). We described the processes for polymer synthesis, nanoparticle formation, transfecting stem cells in vitro, as well as methods for validating the efficacy of VEGF-expressing stem cells for promoting angiogenesis in a murine hindlimb ischemia model.

We describe the method of programming stem cells to overexpress therapeutic factors for angiogenesis using biodegradable polymeric nanoparticles. Processes described include polymer synthesis, transfecting adipose-derived stem cells in vitro, and validating the efficacy of programmed stem cells to promote angiogenesis in a murine hindlimb ischemia model.

Controlled vascular growth is critical for successful tissue regeneration and wound healing, as well as for treating ischemic diseases such as stroke, ...

Ordering Single Cells and Single Embryos in 3D Confinement: A New Device for High Content Screening

Biological cells are usually observed on flat (2D) surfaces. This condition is not physiological, and phenotypes and shapes are highly variable. Screening based on cells in such environments have therefore serious limitations: cell organelles show extreme phenotypes, cell morphologies and sizes are heterogeneous and/or specific cell organelles cannot be properly visualized. In addition, cells in vivo are located in a 3D environment; in this situation, cells show different phenotypes mainly because of their interaction with the surrounding extracellular matrix of the tissue. In order to standardize and generate order of single cells in a physiologically-relevant 3D environment for cell-based assays, we report here the microfabrication and applications of a device for in vitro 3D cell culture. This device consists of a 2D array of microcavities (typically 105 cavities/cm2), each filled with single cells or embryos. Cell position, shape, polarity and internal cell organization become then normalized showing a 3D architecture. We used replica molding to pattern an array of microcavities, &#8216;eggcups&#8217;, onto a thin polydimethylsiloxane (PDMS) layer adhered on a coverslip. Cavities were covered with fibronectin to facilitate adhesion. Cells were inserted by centrifugation. Filling percentage was optimized for each system allowing up to 80%. Cells and embryos viability was confirmed. We applied this methodology for the visualization of cellular organelles, such as nucleus and Golgi apparatus, and to study active processes, such as the closure of the cytokinetic ring during cell mitosis. This device allowed the identification of new features, such as periodic accumulations and inhomogeneities of myosin and actin during the cytokinetic ring closure and compacted phenotypes for Golgi and nucleus alignment. We characterized the method for mammalian cells, fission yeast, budding yeast, C. elegans with specific adaptation in each case. Finally, the characteristics of this device make it particularly interesting for drug screening assays and personalized medicine.

We report a device and a new method to study cells and embryos. Single cells are precisely ordered in microcavity arrays. Their 3D confinement is a step towards 3D environments encountered in physiological conditions and allows organelle orientation. By controlling cell shape, this setup minimizes variability reported in standard assays.

Biological cells are usually observed on flat (2D) surfaces. This condition is not physiological, and phenotypes and shapes are highly variable. Screening ...

Optimizing Attachment of Human Mesenchymal Stem Cells on Poly(&#949;-caprolactone) Electrospun Yarns

Research into biomaterials and tissue engineering often includes cell-based in vitro investigations, which require initial knowledge of the starting cell number. While researchers commonly reference their seeding density this does not necessarily indicate the actual number of cells that have adhered to the material in question. This is particularly the case for materials, or scaffolds, that do not cover the base of standard cell culture well plates. This study investigates the initial attachment of human mesenchymal stem cells seeded at a known number onto electrospun poly(&#949;-caprolactone) yarn after 4 hr in culture. Electrospun yarns were held within several different set-ups, including bioreactor vessels rotating at 9 rpm, cell culture inserts positioned in low binding well plates and polytetrafluoroethylene (PTFE) troughs placed within petri dishes. The latter two were subjected to either static conditions or positioned on a shaker plate (30 rpm). After 4 hr incubation at 37&#160;oC, 5% CO2, the location of seeded cells was determined by cell DNA assay. Scaffolds were removed from their containers and placed in lysis buffer. The media fraction was similarly removed and centrifuged &#8211; the supernatant discarded and pellet broken up with lysis buffer. Lysis buffer was added to each receptacle, or well, and scraped to free any cells that may be present. The cell DNA assay determined the percentage of cells present within the scaffold, media and well fractions. Cell attachment was low for all experimental set-ups, with greatest attachment (30%) for yarns held within cell culture inserts and subjected to shaking motion. This study raises awareness to the actual number of cells attaching to scaffolds irrespective of the stated cell seeding density.

Optimizing Attachment of Human Mesenchymal Stem Cells on Poly(&amp;#949;-caprolactone) Electrospun Yarns

This article describes a range of set-ups for seeding human mesenchymal stem cells onto materials, in this case electrospun yarns, that do not cover the base of standard culture well plates in order to maximize and quantify the number of cells that initially attach compared to the known seeding density.

Research into biomaterials and tissue engineering often includes cell-based in vitro investigations, which require initial knowledge of the starting cell ...

Isolation of Mesenchymal Stem Cells from Human Alveolar Periosteum and Effects of Vitamin D on Osteogenic Activity of Periosteum-derived Cells

Mesenchymal stem cells (MSCs) are present in a variety of tissues and can be differentiated into numerous cell types, including osteoblasts. Among the dental sources of MSCs, the periosteum is an easily accessible tissue, which has been identified to contain MSCs in the cambium layer. However, this source has not yet been widely studied.
Vitamin D3 and 1,25-(OH)2D3 have been demonstrated to stimulate in vitro differentiation of MSCs into osteoblasts. In addition, vitamin C facilitates collagen formation and bone cell growth. However, no study has yet investigated the effects of Vitamin D3 and Vitamin C on MSCs.
Here, we present a method of isolating MSCs from human alveolar periosteum and examine the hypothesis that 1,25-(OH)2D3 may exert an osteoinductive effect on these cells. We also investigate the presence of MSCs in the human alveolar periosteum and assess stem cell adhesion and proliferation. To assess the ability of vitamin C (as a control) and various concentrations of 1,25-(OH)2D3 (10&#8722;10, 10&#8722;9, 10&#8722;8, and 10&#8722;7 M) to alter key mRNA biomarkers in isolated MSCs mRNA expression of alkaline phosphatase (ALP), bone sialoprotein (BSP), core binding factor alpha-1 (CBFA1), collagen-1, and osteocalcin (OCN) are measured using real-time polymerase chain reaction (RT-PCR).

We present a protocol to investigate the mRNA expression biomarkers of periosteum-derived cells (PDCs) induced by vitamin C (vitamin C) and 1,25-dihydroxy vitamin D [1,25-(OH)2D3]. In addition, we evaluate the ability of PDCs to differentiate into osteocytes, chondrocytes, and adipocytes.

Mesenchymal stem cells (MSCs) are present in a variety of tissues and can be differentiated into numerous cell types, including osteoblasts. Among the ...

Scalable Generation of Mature Cerebellar Organoids from Human Pluripotent Stem Cells and Characterization by Immunostaining

The cerebellum plays a critical role in the maintenance of balance and motor coordination, and a functional defect in different cerebellar neurons can trigger cerebellar dysfunction. Most of the current knowledge about disease-related neuronal phenotypes is based on postmortem tissues, which makes understanding of disease progression and development difficult. Animal models and immortalized cell lines have also been used as models for neurodegenerative disorders. However, they do not fully recapitulate human disease. Human induced pluripotent stem cells (iPSCs) have great potential for disease modeling and provide a valuable source for regenerative approaches. In recent years, the generation of cerebral organoids from patient-derived iPSCs improved the prospects for neurodegenerative disease modeling. However, protocols that produce large numbers of organoids and a high yield of mature neurons in 3D culture systems are lacking. The protocol presented is a new approach for reproducible and scalable generation of human iPSC-derived organoids under chemically-defined conditions using scalable single-use bioreactors, in which organoids acquire cerebellar identity. The generated organoids are characterized by the expression of specific markers at both mRNA and protein level. The analysis of specific groups of proteins allows the detection of different cerebellar cell populations, whose localization is important for the evaluation of organoid structure. Organoid cryosectioning and further immunostaining of organoid slices are used to evaluate the presence of specific cerebellar cell populations and their spatial organization.

This protocol describes a dynamic culture system to produce controlled size aggregates of human pluripotent stem cells and further stimulate differentiation in cerebellar organoids under chemically-defined and feeder-free conditions using a single-use bioreactor.

The cerebellum plays a critical role in the maintenance of balance and motor coordination, and a functional defect in different cerebellar neurons can ...

Single-Cell Optical Action Potential Measurement in Human Induced Pluripotent Stem Cell-Derived Cardiomyocytes

Conventional intracellular microelectrode techniques to quantify cardiomyocyte electrophysiology are extremely complex, labor intensive, and typically carried out in low throughput. Rapid and ongoing expansion of induced pluripotent stem cell (iPSC) technology presents a new standard in cardiovascular research and alternate methods are now necessary to increase throughput of electrophysiological data at a single cell level. VF2.1Cl is a recently derived voltage sensitive dye which provides a rapid single channel, high magnitude response to fluctuations in membrane potential. It possesses kinetics superior to those of other existing voltage indicators and makes available functional data equivalent to that of traditional microelectrode techniques. Here, we demonstrate simplified, non-invasive action potential characterization in externally paced human iPSC derived cardiomyocytes using a modular and highly affordable photometry system.

Here we describe optical acquisition and characterization of action potentials from induced pluripotent stem cell derived cardiomyocytes using a high-speed modular photometry system.

Conventional intracellular microelectrode techniques to quantify cardiomyocyte electrophysiology are extremely complex, labor intensive, and typically ...

A Culture Method to Maintain Quiescent Human Hematopoietic Stem Cells

Human hematopoietic stem cells (HSCs), like other mammalian HSCs, maintain lifelong hematopoiesis in the bone marrow. HSCs remain quiescent in vivo, unlike more differentiated progenitors, and enter the cell cycle rapidly after chemotherapy or irradiation to treat bone marrow injury or in vitro culture. By mimicking the bone marrow microenvironment in the presence of abundant fatty acids, cholesterol, low concentration of cytokines, and hypoxia, human HSCs maintain quiescence in vitro. Here, a detailed protocol for maintaining functional HSCs in the quiescent state in vitro is described. This method will enable studies of the behavior of human HSCs under physiological conditions.

This protocol enables the maintenance of quiescent human hematopoietic stem cells in vitro by mimicking the bone marrow microenvironment using abundant fatty acids, cholesterol, lower concentrations of cytokines, and hypoxia.

Human hematopoietic stem cells (HSCs), like other mammalian HSCs, maintain lifelong hematopoiesis in the bone marrow. HSCs remain quiescent in vivo, ...

Biomolecular Imaging of Cellular Uptake of Nanoparticles using Multimodal Nonlinear Optical Microscopy

Probing gold nanoparticles (AuNPs) in living systems is essential to reveal the interaction between AuNPs and biological tissues. Moreover, by integrating nonlinear optical signals such as stimulated Raman scattering (SRS), two-photon excited fluorescence (TPEF), and transient absorption (TA) into an imaging platform, it can be used to reveal biomolecular contrast of cellular structures and AuNPs in a multimodal manner. This article presents a multimodal nonlinear optical microscopy and applies it to perform chemically specific imaging of AuNPs in cancer cells. This imaging platform provides a novel approach for developing more efficient functionalized AuNPs and determining whether they are within vasculatures surrounding the tumor, pericellular, or cellular spaces.

This article presents the integration of a spectral-focusing module and a dual-output pulse laser, enabling rapid hyperspectral imaging of gold nanoparticles and cancer cells. This work aims to demonstrate the details of multimodal nonlinear optical techniques on a standard laser scanning microscope.

Probing gold nanoparticles (AuNPs) in living systems is essential to reveal the interaction between AuNPs and biological tissues. Moreover, by integrating ...