Name: evaluation of extracellular vesicle function during malaria infection
Uploaded: 2018-02-14T14:30:00
Description: Watch this Scientific Journal Video about Evaluation of Extracellular Vesicle Function During Malaria Infection at JoVE.com

This study was financially supported in part by the Novartis foundation for medical- and biological research (to PYM), the Gottfried and Julia Bangerter-Rhyner-Stiftung (to MW and PYM), and the research pool of the University of Fribourg (to PYM). Additional grants include the Swiss Government Excellence Scholarships for Foreign Scholars (to KAB and SM). We thank Isabelle Fellay and Solange Kharoubi Hess for technical support.

Human RBCs were obtained from the blood of healthy donors, in accordance with the guidelines of Swissethics (swissethics.ch).
NOTE: P. falciparum parasite cultures (3D7) and EV production were previously described in Mbagwu, et al.11 Because P. falciparum is a human pathogen, consult the local regulations for handling. The cultures should be kept sterile the entire time.
1. Fluorescence Labeling of EVs
<p class="j...

<ol>
	<li>WHO. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> WHO Malaria Report 2015. , (2015).</li><li>Miller, L. H., Baruch, D. I., Marsh, K., Doumbo, O. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+pathogenic+basis+of+malaria.">The pathogenic basis of malaria.</a> Nature. 415 (6872), 673-679 (2002).</li><li>Mantel, P. Y., Marti, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+role+of+extracellular+vesicles+in+Plasmodium+and+other+protozoan+parasites.">The role of extracellular vesicles in Plasmodium and other protozoan parasites.</a> Cell Microbiol. 16 (3), 344-354 (2014).</li><li>Couper, K. N., 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=Parasite-derived+plasma+microparticles+contribute+significantly+to+malaria+infection-induced+inflammation+through+potent+macrophage+stimulation.">Parasite-derived plasma microparticles contribute significantly to malaria infection-induced inflammation through potent macrophage stimulation.</a> PLoS Pathog. 6 (1), e1000744 (2010).</li><li>Schofield, L., Grau, G. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Immunological+processes+in+malaria+pathogenesis.">Immunological processes in malaria pathogenesis.</a> Nat Rev Immunol. 5 (9), 722-735 (2005).</li><li>Mantel, P. 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=Malaria-infected+erythrocyte-derived+microvesicles+mediate+cellular+communication+within+the+parasite+population+and+with+the+host+immune+system.">Malaria-infected erythrocyte-derived microvesicles mediate cellular communication within the parasite population and with the host immune system.</a> Cell Host Microbe. 13 (5), 521-534 (2013).</li><li>Regev-Rudzki, N., 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=Cell-cell+communication+between+malaria-infected+red+blood+cells+via+exosome-like+vesicles.">Cell-cell communication between malaria-infected red blood cells via exosome-like vesicles.</a> Cell. 153 (5), 1120-1133 (2013).</li><li>Szempruch, A. 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=Extracellular+Vesicles+from+Trypanosoma+brucei+Mediate+Virulence+Factor+Transfer+and+Cause+Host+Anemia.">Extracellular Vesicles from Trypanosoma brucei Mediate Virulence Factor Transfer and Cause Host Anemia.</a> Cell. 164 (1-2), 246-257 (2016).</li><li>Bartel, D. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=MicroRNAs:+genomics,+biogenesis,+mechanism,+and+function.">MicroRNAs: genomics, biogenesis, mechanism, and function.</a> Cell. 116 (2), 281-297 (2004).</li><li>Mantel, P. 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=Infected+erythrocyte-derived+extracellular+vesicles+alter+vascular+function+via+regulatory+Ago2-miRNA+complexes+in+malaria.">Infected erythrocyte-derived extracellular vesicles alter vascular function via regulatory Ago2-miRNA complexes in malaria.</a> Nat Commun. 7, 12727 (2016).</li><li>Mbagwu, S., Walch, M., Filgueira, L., Mantel, P. Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Production+and+Characterization+of+Extracellular+Vesicles+in+Malaria.">Production and Characterization of Extracellular Vesicles in Malaria.</a> Methods Mol Biol. 1660, 377-388 (2017).</li><li>Schweitzer, K. 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=Characterization+of+a+newly+established+human+bone+marrow+endothelial+cell+line:+distinct+adhesive+properties+for+hematopoietic+progenitors+compared+with+human+umbilical+vein+endothelial+cells.">Characterization of a newly established human bone marrow endothelial cell line: distinct adhesive properties for hematopoietic progenitors compared with human umbilical vein endothelial cells.</a> Lab Invest. 76 (1), 25-36 (1997).</li><li>Wong, W., Farr, R., Joglekar, M., Januszewski, A., Hardikar, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Probe-based+Real-time+PCR+Approaches+for+Quantitative+Measurement+of+microRNAs.">Probe-based Real-time PCR Approaches for Quantitative Measurement of microRNAs.</a> J Vis Exp. (98), (2015).</li><li>Mulcahy, L. A., Pink, R. C., Carter, D. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Routes+and+mechanisms+of+extracellular+vesicle+uptake.">Routes and mechanisms of extracellular vesicle uptake.</a> J Extracell Vesicles. 3, (2014).</li><li>French, K. C., Antonyak, M. A., Cerione, 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=Extracellular+vesicle+docking+at+the+cellular+port:+Extracellular+vesicle+binding+and+uptake.">Extracellular vesicle docking at the cellular port: Extracellular vesicle binding and uptake.</a> Semin Cell Dev Biol. 67, 48-55 (2017).</li><li>Montecalvo, A., 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=Mechanism+of+transfer+of+functional+microRNAs+between+mouse+dendritic+cells+via+exosomes.">Mechanism of transfer of functional microRNAs between mouse dendritic cells via exosomes.</a> Blood. 119 (3), 756-766 (2012).</li><li>Idro, R., Jenkins, N. E., Newton, C. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pathogenesis,+clinical+features,+and+neurological+outcome+of+cerebral+malaria.">Pathogenesis, clinical features, and neurological outcome of cerebral malaria.</a> Lancet Neurol. 4 (12), 827-840 (2005).</li><li>Jambou, 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=Plasmodium+falciparum+adhesion+on+human+brain+microvascular+endothelial+cells+involves+transmigration-like+cup+formation+and+induces+opening+of+intercellular+junctions.">Plasmodium falciparum adhesion on human brain microvascular endothelial cells involves transmigration-like cup formation and induces opening of intercellular junctions.</a> PLoS Pathog. 6 (7), e1001021 (2010).</li><li>Zhou, 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=Cancer-secreted+miR-105+destroys+vascular+endothelial+barriers+to+promote+metastasis.">Cancer-secreted miR-105 destroys vascular endothelial barriers to promote metastasis.</a> Cancer Cell. 25 (4), 501-515 (2014).</li></ol>

Several parasites, including Toxoplasma, Trypanosoma, Leishmania, and Trichomonas trigger the release of EVs by the infected host cell. Depending on the pathogens, the released EVs can modulate the host immune response or mediate cellular communication between the parasites6. Yet, there is little evidence suggesting how these small vesicles contribute to malaria disease. Here, we have described several ways to investigate the function of EVs during Plasmodium infection. For instance, the ...

According to the World Health Organization, there were 212 million new cases of malaria worldwide in 2015 and approximately 429,000 people died, mainly children under five years of age1. The mechanisms leading to severe disease, which is often associated with vascular dysfunction, remain ill-defined2. Plasmodium-iRBCs secrete small bi-lipid membrane spheres known as extracellular vesicles (EVs). It is known that these EVs are potentially relevant to the infection process and to the host immune response to infection; however, little is known about the exact function of these small vesicles during malaria infection3. It is possible that they play two important roles: on one hand, they might contribute to the pathogenesis by activating macrophages4,5; and on the other hand, they might mediate cellular communication between parasites and between parasites and host6,7. In fact, parasites can transfer proteins or nucleic acids between each other via EVs. For example, Trypanosoma brucei rhodesiense EVs can transfer virulence factor Serum Resistance-Associated (SRA), and can target both other T. brucei and host erythrocytes8. Furthermore, P. falciparum-iRBCs communicate between each other by transferring nucleic acids within EVs. This allows the parasites to optimize and synchronize its growth. In fact, EVs might be the major regulator of gametocyte conversion, and therefore contribute to the regulation of the transmission stage7.
Not only do EVs regulate the parasites, they also mediate parasite-host interactions. We recently discovered that EVs from iRBCs contain host-derived microRNAs (miRNAs; small RNA species in the range of 21-25 nucleotides9) that were taken up by human endothelial cells. The miRNAs in the EVs form a stable complex with Ago2 (a member of the RNA-induced silencing complex), which once delivered to the recipient cells, is capable of specifically silencing gene expression and affecting the barrier properties of the cells10. Standard protocols have been developed to investigate the function of EVs. Here, we describe first a protocol that allows the fluorescent labeling of EVs to investigate their uptake by recipient cells. In addition, by using a confocal microscope, it is possible to track the EV&#39;s fate inside the cell. Several fluorescent dyes can be used to track EVs. The amine-reactive dye, 5-(and-6)-Carboxyfluorescein Diacetate Succinimidyl Ester (CFSE) and Calcein-AM become fluorescent once inside the vesicles. We prefer to use the amphiphilic label, PKH, because it gives a brighter and more uniform signal. This approach provides important information to understand the interactions between EVs and recipient cells. While in some cases EVs bind to the surface of the cells, some vesicles are rapidly taken up. Upon uptake, EVs deliver their cargoes to the cells, in which they exert their regulatory functions.
Here, we describe a protocol to measure the barrier function of the endothelial cells in vitro by quantifying the transfer of a fluorescent dextran through a cellular monolayer. More sensitive tracers can be used such as radiolabeled markers. However, they require special safety precautions for use. Other assays exist to measure the in vitro barrier function such as transendothelial electrical resistance (TEER), which measures tight junction integrity. Finally visualizing ZO-1, a tight junction protein, by immunofluorescence allows assessment of tight junction integrity as well10. Since EVs are complex and heterogeneous entities containing several cargoes with potential regulatory characteristic, it is useful to overexpress a specific RNA to study its effect on the recipient cell. Therefore, we also define a protocol that aims to generate stable cell lines expressing the miRNA of interest10.

<table>
	<tbody>
		<tr>
			<td>PKH67 Green Fluorescent Cell Linker Mini Kit</td>
			<td>Sigma-Aldrich</td>
			<td>MINI67-1KT</td>
			<td></td>
		</tr>
		<tr>
			<td>Diluent C</td>
			<td>Sigma-Aldrich</td>
			<td>G8278</td>
			<td></td>
		</tr>
		<tr>
			<td>poly-L-lysine</td>
			<td>Sigma-Aldrich</td>
			<td>P8920</td>
			<td></td>
		</tr>
		<tr>
			<td>PBS</td>
			<td>ThermoFisher - Gibco</td>
			<td>10010023</td>
			<td></td>
		</tr>
		<tr>
			<td>Phalloidin CF594</td>
			<td>Biotium</td>
			<td>#00045</td>
			<td></td>
		</tr>
		<tr>
			<td>Hoechst 33342</td>
			<td>ThermoFisher</td>
			<td>H3570</td>
			<td></td>
		</tr>
		<tr>
			<td>ProLong Gold Antifade Mountant</td>
			<td>ThermoFisher</td>
			<td>P36934</td>
			<td></td>
		</tr>
		<tr>
			<td>Rhodamine B isothiocyanate&#8211;Dextran</td>
			<td>ThermoFisher</td>
			<td>R9379-250MG</td>
			<td></td>
		</tr>
		<tr>
			<td>Insert with PET membrane transparent Falcon&#160;for plate 24 wells</td>
			<td>Falcon</td>
			<td>353095</td>
			<td></td>
		</tr>
		<tr>
			<td>Endothelial Cell Growth&#160;Medium MV</td>
			<td>Promocell</td>
			<td>C-22020</td>
			<td></td>
		</tr>
		<tr>
			<td>Puromycin dihydrochloride</td>
			<td>Sigma-Aldrich</td>
			<td>P9620-10ML</td>
			<td></td>
		</tr>
		<tr>
			<td>MTS Cell Proliferation Colorimetric Assay Kit</td>
			<td>Biovision</td>
			<td>K300-500</td>
			<td></td>
		</tr>
		<tr>
			<td>hexadimethrine bromide</td>
			<td>Sigma-Aldrich</td>
			<td>107689-10G</td>
			<td></td>
		</tr>
		<tr>
			<td>MISSION&#160;Lenti microRNA, Human hsa-miR-451a</td>
			<td>Sigma-Aldrich</td>
			<td>HLMIR0583</td>
			<td></td>
		</tr>
		<tr>
			<td>MISSION Lenti microRNA, ath-miR416, Negative Control 1 Transduction Particles</td>
			<td>Sigma-Aldrich</td>
			<td>NCLMIR001</td>
			<td></td>
		</tr>
		<tr>
			<td>MISSION&#160;Lenti microRNA, Human</td>
			<td>Sigma-Aldrich</td>
			<td>NCLMIR0001</td>
			<td></td>
		</tr>
		<tr>
			<td>Leica TCS SP5</td>
			<td>Leica Microsystems</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>miRNeasy mini Kit</td>
			<td>Qiagen</td>
			<td>217004</td>
			<td></td>
		</tr>
		<tr>
			<td>TaqMan MicroRNA Reverse Transcription Kit 1000 reactions</td>
			<td>ThermoFisher</td>
			<td>4366597</td>
			<td></td>
		</tr>
		<tr>
			<td>hsa-mir-451a&#160;RT/750 PCR rxns</td>
			<td>ThermoFisher</td>
			<td>001141</td>
			<td></td>
		</tr>
		<tr>
			<td>U6 snRNA</td>
			<td>ThermoFisher</td>
			<td>001973</td>
			<td></td>
		</tr>
		<tr>
			<td>TaqMan Universal Master Mix II, with UNG</td>
			<td>ThermoFisher</td>
			<td>4440038</td>
			<td></td>
		</tr>
		<tr>
			<td>StepOnePlus Real-Time PCR System</td>
			<td>ThermoFisher</td>
			<td>4376600</td>
			<td></td>
		</tr>
	</tbody>
</table>

evaluation of extracellular vesicle function during malaria infection

Malaria is a life-threatening disease caused by Plasmodium parasites, with P. falciparum being the most prevalent on the African continent and responsible for most malaria-related deaths globally. Several factors including parasite sequestration in tissues, vascular dysfunction, and inflammatory responses influence the evolution of the disease in malaria-infected people. P. falciparum-infected red blood cells (iRBCs) release small extracellular vesicles (EVs) containing different kinds of cargo molecules that mediate pathogenesis and cellular communication between parasites and host. EVs are efficiently taken up by cells in which they modulate their function. Here we discuss strategies to address the role of EVs in parasite-host interactions. First, we describe a straightforward method for labeling and tracking EV internalization by endothelial cells, using a green cell linker dye. Second, we report a simple way to measure permeability across an endothelial cell monolayer by using a fluorescently labeled dextran. Finally, we show how to investigate the role of small non-coding RNA molecules in endothelial cell function.

Here, we describe protocols to investigate the interactions of EVs with host cells. The uptake of fluorescently labeled EVs is monitored by confocal microscopy (Figure 1). Endothelial cells efficiently take up EVs, however the incubation time with EVs can be optimized to track the uptake. For a better localization of EVs inside the cells, stain actin with phalloidin. Next, we use a filter membrane on top of which a monolayer of endothelial cells grows. Rhodam...

Watch this Scientific Journal Video about Evaluation of Extracellular Vesicle Function During Malaria Infection at JoVE.com

Evaluation of Extracellular Vesicle Function During Malaria Infection

In this work, we describe protocols to investigate the role of extracellular vesicles (EVs) released by Plasmodium falciparum infected erythrocytes. In particular, we focus on the interactions of EVs with endothelial cells.

Malaria is a life-threatening disease caused by Plasmodium parasites, with P. falciparum being the most prevalent on the African continent and responsible ...

Research

JoVE Journal

Immunology and Infection

Neutrophil Extracellular Traps: How to Generate and Visualize Them

Neutrophil granulocytes are the most abundant group of leukocytes in the peripheral blood. As professional phagocytes, they engulf bacteria and kill them ...

A Simple Chelex Protocol for DNA Extraction from Anopheles spp.

A Simple Chelex Protocol for DNA Extraction from Anopheles spp.

Endemic countries are increasingly adopting molecular tools for  efficient typing, identification and surveillance against malaria parasites and  vector ...

2D and 3D Chromosome Painting in Malaria Mosquitoes

Fluorescent in situ hybridization (FISH) of whole arm chromosome probes is a robust technique for mapping genomic regions of interest, detecting ...

Evaluation of Blood Lactate and Plasma Insulin During High-intensity Exercise by Antecubital Vein Catheterization

The measurement of metabolic and endocrinal markers during physical activity is of relevance to understanding the physiological implications of different ...

Imaging Ca2+ Responses During Shigella Infection of Epithelial Cells

Imaging Ca2+ Responses During Shigella Infection of Epithelial Cells

Ca2+ is a ubiquitous ion involved in all known cellular processes. While global Ca2+ responses may affect cell fate, local variations in free Ca2+ ...

Mouse Body Temperature Measurement Using Infrared Thermometer During Passive Systemic Anaphylaxis and Food Allergy Evaluation

Mouse body temperature measurement is of paramount importance for investigating allergies and anaphylactic symptoms. Rectal probes for temperature ...

Automated Image-Based Quantification of Neutrophil Extracellular Traps Using NETQUANT

Neutrophil extracellular traps (NETs) are web-like antimicrobial structures consisting of DNA and granule derived antimicrobial proteins. ...

Evaluation of Host-Pathogen Responses and Vaccine Efficacy in Mice

Vaccines are a 20th century medical marvel. They have dramatically reduced the morbidity and mortality caused by infectious diseases and contributed to a ...

Purification of High Yield Extracellular Vesicle Preparations Away from Virus

One of the major hurdles in the field of extracellular vesicle (EV) research today is the ability to achieve purified EV preparations in a viral infection ...