Name: automated imaging and analysis for the quantification of fluorescently labeled macropinosomes
Uploaded: 2021-08-24T15:00:00
Description: Watch this Scientific Journal Video about Automated Imaging and Analysis for the Quantification of Fluorescently Labeled Macropinosomes at JoVE.com

This work was supported by NIH/NCI grants (R01CA207189, R21CA243701) to C.C. KMO.G. is a recipient of a TRDRP Postdoctoral Fellowship Award (T30FT0952). The BioTek Cytation 5 is a part of the Sanford Burnham Prebys Cell Imaging Core, which receives financial support from the NCI Cancer Center Support Grant (P30 CA030199). Figures 1-3 were created using BioRender.

1. Preparation of materials
<ol>
	<li>Dissolve 70 kDa dextran labeled with FITC or tetramethylrhodamine (TMR) in PBS to obtain a 20 mg/mL solution. Store the aliquots at -20 &#176;C.</li>
	<li>Dissolve DAPI in ddH2O to obtain a 1 mg/mL solution. Store the aliquots at -20 &#176;C. 
	CAUTION: DAPI is a potential carcinogen and should be handled with care.</li>
	<li>On the day of fixation, prepare fresh 3.7% ACS grade formaldehyde in PBS. 
	CAUTION: Formaldehyde is a fixative, known carcinogen and is ...

<ol>
	<li>Lin, X. P., Mintern, J. D., Gleeson, P. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Macropinocytosis+in+different+cell+types:+similarities+and+differences.">Macropinocytosis in different cell types: similarities and differences.</a> Membranes. 10 (8), 21 (2020).</li><li>Recouvreux, M. V., Commisso, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Macropinocytosis:+a+metabolic+adaptation+to+nutrient+stress+in+cancer.">Macropinocytosis: a metabolic adaptation to nutrient stress in cancer.</a> Frontiers in Endocrinology. 8, (2017).</li><li>Zhang, Y. J., Commisso, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Macropinocytosis+in+cancer:+a+complex+signaling+network.">Macropinocytosis in cancer: a complex signaling network.</a> Trends in Cancer. 5 (6), 332-334 (2019).</li><li>Commisso, C., 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=Macropinocytosis+of+protein+is+an+amino+acid+supply+route+in+Ras-transformed+cells.">Macropinocytosis of protein is an amino acid supply route in Ras-transformed cells.</a> Nature. 497 (7451), 633-637 (2013).</li><li>Kim, S. M., 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=PTEN+deficiency+and+AMPK+activation+promote+nutrient+scavenging+and+anabolism+in+prostate+cancer+cells.">PTEN deficiency and AMPK activation promote nutrient scavenging and anabolism in prostate cancer cells.</a> Cancer Discovery. 8 (7), 866-883 (2018).</li><li>Jayashankar, V., Edinger, A. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Macropinocytosis+confers+resistance+to+therapies+targeting+cancer+anabolism.">Macropinocytosis confers resistance to therapies targeting cancer anabolism.</a> Nature Communications. 11 (1), (2020).</li><li>Kamphorst, J. 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=Human+pancreatic+cancer+tumors+are+nutrient+poor+and+tumor+cells+actively+scavenge+extracellular+protein.">Human pancreatic cancer tumors are nutrient poor and tumor cells actively scavenge extracellular protein.</a> Cancer Research. 75 (3), 544-553 (2015).</li><li>Olivares, O., 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=Collagen-derived+proline+promotes+pancreatic+ductal+adenocarcinoma+cell+survival+under+nutrient+limited+conditions.">Collagen-derived proline promotes pancreatic ductal adenocarcinoma cell survival under nutrient limited conditions.</a> Nature Communications. 8, (2017).</li><li>Seguin, L., 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=Galectin-3,+a+druggable+vulnerability+for+KRAS-addicted+cancers.">Galectin-3, a druggable vulnerability for KRAS-addicted cancers.</a> Cancer Discovery. 7 (12), 1464-1479 (2017).</li><li>Redelman-Sidi, G., 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+canonical+Wnt+pathway+drives+macropinocytosis+in+cancer.">The canonical Wnt pathway drives macropinocytosis in cancer.</a> Cancer Research. 78 (16), 4658-4670 (2018).</li><li>Tejeda-Munoz, N., Albrecht, L. V., Bui, M. H., De Robertis, E. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Wnt+canonical+pathway+activates+macropinocytosis+and+lysosomal+degradation+of+extracellular+proteins.">Wnt canonical pathway activates macropinocytosis and lysosomal degradation of extracellular proteins.</a> Proceedings of the National Academy of Sciences of the United States of America. 116 (21), 10402-10411 (2019).</li><li>Schmees, C., 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=Macropinocytosis+of+the+PDGF+beta-receptor+promotes+fibroblast+transformation+by+H-RasG12V.">Macropinocytosis of the PDGF beta-receptor promotes fibroblast transformation by H-RasG12V.</a> Molecular Biology of the Cell. 23 (13), 2571-2582 (2012).</li><li>Lee, S. -. W., 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=EGFR-Pak+signaling+selectively+regulates+glutamine+deprivation-induced+macropinocytosis.">EGFR-Pak signaling selectively regulates glutamine deprivation-induced macropinocytosis.</a> Developmental Cell. 50 (3), 381-392 (2019).</li><li>Recouvreux, M. 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=Glutamine+depletion+regulates+Slug+to+promote+EMT+and+metastasis+in+pancreatic+cancer.">Glutamine depletion regulates Slug to promote EMT and metastasis in pancreatic cancer.</a> Journal of Experimental Medicine. 217 (9), (2020).</li><li>Zhang, Y., 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=Macropinocytosis+in+cancer-associated+fibroblasts+is+dependent+on+CaMKK2/ARHGEF2+signaling+and+functions+to+support+tumor+and+stromal+cell+fitness.">Macropinocytosis in cancer-associated fibroblasts is dependent on CaMKK2/ARHGEF2 signaling and functions to support tumor and stromal cell fitness.</a> Cancer Discovery. 11 (7), 1808-1825 (2021).</li><li>Su, H., 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=Cancer+cells+escape+autophagy+inhibition+via+NRF2-induced+macropinocytosis.">Cancer cells escape autophagy inhibition via NRF2-induced macropinocytosis.</a> Cancer Cell. 39 (5), 678-693 (2021).</li><li>Bar-Sagi, D., Feramisco, J. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Induction+of+membrane+ruffling+and+fluid-phase+pinocytosis+in+quiescent+fibroblasts+by+ras+proteins.">Induction of membrane ruffling and fluid-phase pinocytosis in quiescent fibroblasts by ras proteins.</a> Science. 233 (4768), 1061-1068 (1986).</li><li>Mishra, 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=Stromal+epigenetic+alterations+drive+metabolic+and+neuroendocrine+prostate+cancer+reprogramming.">Stromal epigenetic alterations drive metabolic and neuroendocrine prostate cancer reprogramming.</a> Journal of Clinical Investigation. 128 (10), 4472-4484 (2018).</li><li>Commisso, C., Flinn, R. J., Bar-Sagi, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Determining+the+macropinocytic+index+of+cells+through+a+quantitative+image-based+assay.">Determining the macropinocytic index of cells through a quantitative image-based assay.</a> Nature Protocols. 9 (1), 182-192 (2014).</li><li>Galenkamp, K. M. O., Alas, B., Commisso, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Quantitation+of+macropinocytosis+in+cancer+cells.">Quantitation of macropinocytosis in cancer cells.</a> Methods in Molecular Biology. 1928, 113-123 (2019).</li><li>Wang, J. T. H., Teasdale, R. D., Liebl, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Macropinosome+quantitation+assay.">Macropinosome quantitation assay.</a> MethodsX. 1, 36-41 (2014).</li><li>Lee, S. -. W., Alas, B., Commisso, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Detection+and+quantification+of+macropinosomes+in+pancreatic+tumors.">Detection and quantification of macropinosomes in pancreatic tumors.</a> Methods in Molecular Biology. 1882, 171-181 (2019).</li><li>Williams, T., Kay, R. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High-throughput+measurement+of+dictyostelium+discoideum+macropinocytosis+by+flow+cytometry.">High-throughput measurement of dictyostelium discoideum macropinocytosis by flow cytometry.</a> Journal of Visualized Experiments: JoVE. (139), e58434 (2018).</li></ol>

The quality of the experiments and data acquisition highly depends on the quality of the reagents, the optimization of the settings, and the cleanliness of the coverslips and microplate. The final results should give minimal variation between replicates; however, biological variations do naturally occur or may otherwise be caused by a number of factors. Cell density may cause cells to respond more or less to macropinocytosis inducers or inhibitors. It is, therefore, crucial to adhere to the 80% confluency as proposed her...

The non-specific endocytic pathway of macropinocytosis allows cells to internalize a variety of extracellular components, including nutrients, proteins, antigens, and pathogens, through bulk uptake of extracellular fluid and its constituents1. Though important for the biology of numerous cell types, increasingly, the macropinocytosis pathway is described to play an essential role in tumor biology, where, through macropinocytic uptake, tumor cells are able to survive and proliferate in the presence of a nutrient-depleted microenvironment2,3. The uptake of extracellular macromolecules, including albumin and extracellular matrix, and necrotic cell debris, provides an alternative nutrient source for biomass production by creating amino acids, sugars, lipids and nucleotides through macropinosome and lysosome fusion-mediated cargo catabolism4,5,6,7,8.
The induction and regulation of macropinocytosis are complex and can vary depending on cellular context. Thus far, several inducers of macropinocytosis have been identified and include ligands, such as epidermal growth factor (EGF), platelet-derived growth factor (PDGF), galectin-3, and Wnt3A9,10,11,12,13. In addition, culturing conditions that mimic the tumor microenvironment can trigger activation of the pathway. Pancreatic ductal adenocarcinoma (PDAC) tumors are nutrient-deprived, especially for the amino acid glutamine, which causes both cancer cells and cancer-associated fibroblasts (CAFs) to rely on macropinocytosis for survival7,13,14,15. Moreover, tumor stresses, such as hypoxia and oxidative stress, can activate this scavenging pathway16. In addition to the numerous extrinsic influencers that can induce macropinocytosis, a variety of intracellular pathways control macropinosome formation. Oncogenic Ras-mediated transformation is sufficient to initiate the macropinocytic machinery, and multiple cancer types exhibit oncogenic Ras-driven constitutive macropinocytosis4,5,9,17. Alternatively, wild-type Ras activation and Ras-independent pathways have been identified to activate macropinocytosis in cancer cells and CAFs10,11,15,18. The use of various in vitro models in combination with inhibitor treatments has resulted in the identification of several macropinocytosis modulators, which include sodium-hydrogen exchangers, the small GTPase Rac1, phosphoinositide 3-kinase (PI3K), p21-activated kinase (Pak), and AMP-activated protein kinase (AMPK)4,13,15. However, given the multitude of described factors and conditions that regulate macropinocytosis, it is conceivable that many more modulators and stimuli remain undiscovered. The identification of novel modulators and stimuli can be facilitated by automated assessment of a multitude of conditions in a single experiment. This methodology can shed light on the factors involved in macropinosome formation and may allow for the discovery of novel small molecules or biologics that target this pathway.
Here, we have adapted our previously established protocol for determining the extent of macropinocytosis in cancer cells in vitro to a 96-well microplate format and automated imaging and quantification19,20. This protocol is based on fluorescent microscopy, which has become a standard in the field to determine macropinocytosis in vitro and in vivo4,5,6,7,9,10,11,12,13,15,16,17,18,19,20,21,22. Macropinosomes can be distinguished from other endocytic pathways through their ability to internalize large macromolecules, such as high molecular weight dextran (i.e., 70 kDa)2,3,4,20,21,22,23. Thus, macropinosomes can be defined through uptake of extracellularly administered fluorophore-labeled 70 kDa dextran. As a result, macropinocytic vesicles manifest as intracellular clusters of fluorescent puncta with sizes ranging from 0.2-5 &#181;m. These puncta can be microscopically imaged and subsequently quantified to determine the extent of macropinocytosis in the cell - &#39;the macropinocytic index&#39;.
In this protocol, the essential steps to visualize macropinosomes in adherent cells in vitro on a 96-well microplate and coverslips using standard laboratory equipment are described (Figure 1). In addition, the directions to automate the image acquisition and quantification of the macropinocytic index using a cell imaging multi-mode plate reader are provided. This automation reduces time, cost, and effort compared to our previously described protocols19,20. In addition, it avoids unintentionally biased imaging acquisition and analysis and thereby enhances reproducibility and reliability. This method can easily be adapted to different cell types or plate readers or be utilized to determine alternative macropinosome features, such as size, number, and location. The herein described method is especially suitable for the screening of cell culture conditions that induce macropinocytosis, the identification of novel modulators, or optimization of drug concentrations of known inhibitors.
<img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/62828/62828fig01.jpg" /> 
Figure 1: Schematic of the automated assay to determine the &#39;macropinocytic index&#39; in adherent cells. Created using BioRender. <a href="https://www.jove.com/files/ftp_upload/62828/62828fig01large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>

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			<td>0.25% Trypsin</td>
			<td>Corning</td>
			<td>25053CI</td>
			<td>0.1% EDTA in HBSS w/o Calcium, Magnesium and Sodium Bicarbonate</td>
		</tr>
		<tr>
			<td>1.5 mL Microcentrifuge tube</td>
			<td>Fisherbrand</td>
			<td>05-408-129</td>
			<td></td>
		</tr>
		<tr>
			<td>10-cm Tissue culture dish</td>
			<td>Greiner Bio-One</td>
			<td>664160</td>
			<td>CELLSTAR</td>
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		<tr>
			<td>15 mL Centrifuge tube</td>
			<td>Fisherbrand</td>
			<td>07-200-886</td>
			<td></td>
		</tr>
		<tr>
			<td>2 L Beaker</td>
			<td>Fisherbrand</td>
			<td>02-591-33</td>
			<td></td>
		</tr>
		<tr>
			<td>24-well Tissue culture plate</td>
			<td>Greiner Bio-One</td>
			<td>662160</td>
			<td>CELLSTAR</td>
		</tr>
		<tr>
			<td>25 mL Reagent reservoir</td>
			<td>Genesee Scientific Corporation</td>
			<td>28-121</td>
			<td></td>
		</tr>
		<tr>
			<td>500 mL Beaker</td>
			<td>Fisherbrand</td>
			<td>02-591-30</td>
			<td></td>
		</tr>
		<tr>
			<td>6-cm Tissue culture dish</td>
			<td>Greiner Bio-One</td>
			<td>628160</td>
			<td>CELLSTAR</td>
		</tr>
		<tr>
			<td>8-Channel aspiration adapter</td>
			<td>Integra Biosciences</td>
			<td>155503</td>
			<td></td>
		</tr>
		<tr>
			<td>8-Channel aspiration adapter for standard tips</td>
			<td>Integra Biosciences</td>
			<td>159024</td>
			<td></td>
		</tr>
		<tr>
			<td>95% Ethanol</td>
			<td>Decon Laboratories Inc</td>
			<td>4355226</td>
			<td></td>
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			<td>Ammonia-free glass cleaner</td>
			<td>Sparkle</td>
			<td>FUN20500CT</td>
			<td></td>
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		<tr>
			<td>Black 96-well high-content screening microplate</td>
			<td>PerkinElmer</td>
			<td>6055300</td>
			<td>CellCarrier-96 Ultra</td>
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		<tr>
			<td>Cotton-tipped applicator</td>
			<td>Fisherbrand</td>
			<td>23-400-101</td>
			<td></td>
		</tr>
		<tr>
			<td>Coverslips</td>
			<td>Fisherbrand</td>
			<td>12-545-80</td>
			<td>12 mm diameter</td>
		</tr>
		<tr>
			<td>Cytation 5 Cell Imaging Multi-Mode Reader</td>
			<td>Biotek</td>
			<td>CYT5FW</td>
			<td></td>
		</tr>
		<tr>
			<td>DAPI</td>
			<td>Millipore Sigma</td>
			<td>5.08741</td>
			<td></td>
		</tr>
		<tr>
			<td>Dextran 70 kDa - FITC</td>
			<td>Life Technologies</td>
			<td>D1822</td>
			<td>Lysine-fixable</td>
		</tr>
		<tr>
			<td>Dextran 70 kDa - TMR</td>
			<td>Life Technologies</td>
			<td>D1819</td>
			<td></td>
		</tr>
		<tr>
			<td>DMSO</td>
			<td>Millipore Sigma</td>
			<td>D1435</td>
			<td></td>
		</tr>
		<tr>
			<td>DPBS</td>
			<td>Corning</td>
			<td>21031CV</td>
			<td>Without Calcium and Magnesium</td>
		</tr>
		<tr>
			<td>Forceps</td>
			<td>Fine Science Tools</td>
			<td>11251-20</td>
			<td>Dumont #5</td>
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		<tr>
			<td>Formaldehyde, 37%</td>
			<td>Ricca Chemical</td>
			<td>RSOF0010-250A</td>
			<td>ACS Reagent Grade</td>
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		<tr>
			<td>Glycerol</td>
			<td>Fisher BioReagents</td>
			<td>BP229-1</td>
			<td></td>
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		<tr>
			<td>Hardening fluorescence mounting media</td>
			<td>Agilent Tech</td>
			<td>S302380-2</td>
			<td>DAKO</td>
		</tr>
		<tr>
			<td>Hoechst 33342</td>
			<td>Millipore Sigma</td>
			<td>B2261</td>
			<td></td>
		</tr>
		<tr>
			<td>Hydrochloric acid (HCl)</td>
			<td>Fisher Chemical</td>
			<td>A144-212</td>
			<td>Certified ACS Plus, 36.5%&#8211;38.0%</td>
		</tr>
		<tr>
			<td>Lint-free wipes</td>
			<td>Kimberly-Clark</td>
			<td>34155</td>
			<td>Kimwipes</td>
		</tr>
		<tr>
			<td>Miscroscope slides</td>
			<td>Fisherbrand</td>
			<td>12-544-1</td>
			<td>Premium plain glass</td>
		</tr>
		<tr>
			<td>Multichannel pipette</td>
			<td>Gilson</td>
			<td>FA10013</td>
			<td>8 channels, 0.5&#8211;10 &#181;L</td>
		</tr>
		<tr>
			<td>Multichannel pipette</td>
			<td>Gilson</td>
			<td>FA10012&#160;</td>
			<td>12 channels, 20&#8211;200 &#181;L</td>
		</tr>
		<tr>
			<td>Multichannel pipette</td>
			<td>Gilson</td>
			<td>FA10011</td>
			<td>8 channels, 20&#8211;200 &#181;L</td>
		</tr>
		<tr>
			<td>Parafilm M</td>
			<td>Pechiney</td>
			<td>PM996</td>
			<td></td>
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			<td>Plastic wrap</td>
			<td>Kirkland Signature</td>
			<td>208733</td>
			<td>Stretch-Tite</td>
		</tr>
		<tr>
			<td>Silicone isolators</td>
			<td>Grace Bio Labs Inc</td>
			<td>664107</td>
			<td>13 mm Diameter X 0.8 mm Depth ID, 25 mm X 25 mm</td>
		</tr>
		<tr>
			<td>Slide adapter</td>
			<td>Biotek</td>
			<td>1220548</td>
			<td></td>
		</tr>
		<tr>
			<td>Wash bottle</td>
			<td>Fisherbrand</td>
			<td>FB0340922C</td>
			<td></td>
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</table>

automated imaging and analysis for the quantification of fluorescently labeled macropinosomes

Macropinocytosis is a non-specific fluid-phase uptake pathway that allows cells to internalize large extracellular cargo, such as proteins, pathogens, and cell debris, through bulk endocytosis. This pathway plays an essential role in a variety of cellular processes, including the regulation of immune responses and cancer cell metabolism. Given this importance in biological function, examining cell culture conditions can provide valuable information by identifying regulators of this pathway and optimizing conditions to be employed in the discovery of novel therapeutic approaches. The study describes an automated imaging and analysis technique using standard laboratory equipment and a cell imaging multi-mode plate reader for the rapid quantification of the macropinocytic index in adherent cells. The automated method is based on the uptake of high molecular weight fluorescent dextran and can be applied to 96-well microplates to facilitate assessments of multiple conditions in one experiment or fixed samples mounted onto glass coverslips. This approach is aimed at maximizing reproducibility and reducing experimental variation while being both time-saving and cost-effective.

When the steps and adjustment of the above-described protocol are followed accordingly, the final experimental results should provide information about whether the studied cell culture conditions or inhibitors induce or reduce macropinocytosis in the cell line of interest. To strengthen the validity of these findings, the inclusion of control conditions will allow for the scrutinization of the results to determine whether the experiment has been completed successfully. Macropinocytosis induction controls will provide inf...

Watch this Scientific Journal Video about Automated Imaging and Analysis for the Quantification of Fluorescently Labeled Macropinosomes at JoVE.com

Automated Imaging and Analysis for the Quantification of Fluorescently Labeled Macropinosomes

Automated assays using multi-well microplates are advantageous approaches for identifying pathway regulators by allowing the assessment of a multitude of conditions in a single experiment. Here, we have adapted the well-established macropinosome imaging and quantification protocol to a 96-well microplate format and provide a comprehensive outline for automation using a multi-mode plate reader.

Macropinocytosis is a non-specific fluid-phase uptake pathway that allows cells to internalize large extracellular cargo, such as proteins, pathogens, and ...

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The physiological process by which new vasculature forms from existing vasculature requires specific signaling events that trigger morphological changes ...

Automated Quantification and Analysis of Cell Counting Procedures Using ImageJ Plugins

The National Institute of Health&#39;s ImageJ is a powerful, freely available image processing software suite. ImageJ has comprehensive particle analysis ...

The Use of Ex Vivo Whole-organ Imaging and Quantitative Tissue Histology to Determine the Bio-distribution of Fluorescently Labeled Molecules

The Use of Ex Vivo Whole-organ Imaging and Quantitative Tissue Histology to Determine the Bio-distribution of Fluorescently Labeled Molecules

Fluorescent labeling is a well-established process for examining the fate of labeled molecules under a variety of experimental conditions both in vitro ...

Open Source High Content Analysis Utilizing Automated Fluorescence Lifetime Imaging Microscopy

We present an open source high content analysis instrument utilizing automated fluorescence lifetime imaging (FLIM) for assaying protein interactions ...

A Rapid Automated Protocol for Muscle Fiber Population Analysis in Rat Muscle Cross Sections Using Myosin Heavy Chain Immunohistochemistry

Quantification of muscle fiber populations provides a deeper insight into the effects of disease, trauma, and various other influences on skeletal muscle ...

Visualization and Quantification of Mesenchymal Cell Adipogenic Differentiation Potential with a Lineage Specific Marker

Several dyes are currently available for use in detecting differentiation of mesenchymal cells into adipocytes. Dyes, such as Oil Red O, are cheap, easy ...