L.M.E. is supported by the DFG research training program GRK2157 entitled &#8220;3D Tissue Models for Studying Microbial Infections by Human Pathogens&#8221; awarded to A. S-U. B.J.K. is supported by a postdoctoral fellowship by the Alexander von Humboldt Foundation. Additionally, we acknowledge Lena Wolter for her technical assistance in the generation of the iPSC-BECs in culture.

<ol>
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S., Greenwood, B., Brandtzaeg, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Epidemic+meningitis,+meningococcaemia,+and+Neisseria+meningitidis.">Epidemic meningitis, meningococcaemia, and Neisseria meningitidis.</a> Lancet. 369 (9580), 2196-2210 (2007).</li><li>Le Guennec, L., Coureuil, M., Nassif, X., Bourdoulous, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Strategies+used+by+bacterial+pathogens+to+cross+the+blood-brain+barrier.">Strategies used by bacterial pathogens to cross the blood-brain barrier.</a> Cellular Microbiology. , (2020).</li><li>Doran, K. 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=Host-pathogen+interactions+in+bacterial+meningitis.">Host-pathogen interactions in bacterial meningitis.</a> Acta Neuropathologica. 131 (2), 185-209 (2016).</li><li>Cunha, C. S. E., Griffiths, N. J., Virji, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Neisseria+meningitidis+opc+invasin+binds+to+the+sulphated+tyrosines+of+activated+vitronectin+to+attach+to+and+invade+human+brain+endothelial+cells.">Neisseria meningitidis opc invasin binds to the sulphated tyrosines of activated vitronectin to attach to and invade human brain endothelial cells.</a> PLoS Pathogens. , (2010).</li><li>Coureuil, 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=Meningococcus+hijacks+a+&#946;2-adrenoceptor/&#946;-arrestin+pathway+to+cross+brain+microvasculature+endothelium.">Meningococcus hijacks a &#946;2-adrenoceptor/&#946;-arrestin pathway to cross brain microvasculature endothelium.</a> Cell. 143 (7), 1149-1160 (2010).</li><li>Bernard, S. 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=Pathogenic+Neisseria+meningitidis+utilizes+CD147+for+vascular+colonization.">Pathogenic Neisseria meningitidis utilizes CD147 for vascular colonization.</a> Nature Medicine. 20 (7), 725-731 (2014).</li><li>Slanina, H., Hebling, S., Hauck, C. R., Schubert-Unkmeir, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cell+invasion+by+neisseria+meningitidis+requires+a+functional+interplay+between+the+focal+adhesion+kinase,+Src+and+cortactin.">Cell invasion by neisseria meningitidis requires a functional interplay between the focal adhesion kinase, Src and cortactin.</a> PLoS ONE. 7 (6), (2012).</li><li>Unkmeir, 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=Fibronectin+mediates+Opc-dependent+internalization+of+Neisseria+meningitidis+in+human+brain+microvascular+endothelial+cells.">Fibronectin mediates Opc-dependent internalization of Neisseria meningitidis in human brain microvascular endothelial cells.</a> Molecular Microbiology. 46 (4), 933-946 (2002).</li><li>Helms, H. 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=In+vitro+models+of+the+blood-brain+barrier:+An+overview+of+commonly+used+brain+endothelial+cell+culture+models+and+guidelines+for+their+use.">In vitro models of the blood-brain barrier: An overview of commonly used brain endothelial cell culture models and guidelines for their use.</a> Journal of Cerebral Blood Flow and Metabolism. , (2015).</li><li>Lippmann, E. 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=Derivation+of+Blood-Brain+Barrier+Endothelial+Cells+from+Human+Pluripotent+Stem+Cells.">Derivation of Blood-Brain Barrier Endothelial Cells from Human Pluripotent Stem Cells.</a> Nature Biotechnology. 30 (8), 783-791 (2012).</li><li>Lippmann, E. S., Al-Ahmad, A., Azarin, S. M., Palecek, S. P., Shusta, E. V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+retinoic+acid-enhanced,+multicellular+human+blood-brain+barrier+model+derived+from+stem+cell+sources.">A retinoic acid-enhanced, multicellular human blood-brain barrier model derived from stem cell sources.</a> Scientific Reports. 4, 4160 (2014).</li><li>Hollmann, E. K., Bailey, A. K., Potharazu, A. V., Neely, M. D., Bowman, A. B., Lippmann, E. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Accelerated+differentiation+of+human+induced+pluripotent+stem+cells+to+blood-brain+barrier+endothelial+cells.">Accelerated differentiation of human induced pluripotent stem cells to blood-brain barrier endothelial cells.</a> Fluids and Barriers of the CNS. , (2017).</li><li>Kim, B. 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S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Past+and+Current+Perspectives+in+Modeling+Bacteria+and+Blood&#8211;Brain+Barrier+Interactions.">Past and Current Perspectives in Modeling Bacteria and Blood&#8211;Brain Barrier Interactions.</a> Frontiers in Microbiology. , (2019).</li><li>Martins Gomes, S. F., 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=Induced+Pluripotent+Stem+Cell-Derived+Brain+Endothelial+Cells+as+a+Cellular+Model+to+Study+Neisseria+meningitidis+Infection.">Induced Pluripotent Stem Cell-Derived Brain Endothelial Cells as a Cellular Model to Study Neisseria meningitidis Infection.</a> Frontiers in Microbiology. , (2019).</li><li>Vatine, G. 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=Modeling+Psychomotor+Retardation+using+iPSCs+from+MCT8-Deficient+Patients+Indicates+a+Prominent+Role+for+the+Blood-Brain+Barrier.">Modeling Psychomotor Retardation using iPSCs from MCT8-Deficient Patients Indicates a Prominent Role for the Blood-Brain Barrier.</a> Cell Stem Cell. , (2016).</li><li>Lim, R. 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=Huntington's+Disease+iPSC-Derived+Brain+Microvascular+Endothelial+Cells+Reveal+WNT-Mediated+Angiogenic+and+Blood-Brain+Barrier+Deficits.">Huntington's Disease iPSC-Derived Brain Microvascular Endothelial Cells Reveal WNT-Mediated Angiogenic and Blood-Brain Barrier Deficits.</a> Cell Reports. 19 (7), 1365-1377 (2017).</li><li>Stebbins, M. J., Wilson, H. K., Canfield, S. 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The authors have nothing to disclose.

Modeling BECs and the BBB has had challenges, as primary and immortalized human BECs, in vitro, tend to lack robust barrier phenotypes. The advent of human&#160;stem cell technologies has&#160;allowed for the generation of&#160;iPSC derived BEC-like cells&#160;that retain expected hallmark&#160;BBB phenotypes such as&#160;endothelial markers, tight&#160;junction expression, barrier&#160;properties, response to other&#160;CNS cell types, and functional&#160;efflux transporters12,</sup...

An erratum was issued for:&#160;<a href="https://www.jove.com/t/61400">Neisseria meningitidis Infection of Induced Pluripotent Stem-Cell Derived Brain Endothelial Cells Larvae</a>. The Authors section was updated from:
Leo M. Endres1 
Alexandra Schubert-Unkmeir1 
Brandon J. Kim1,2 
1Institute for Hygiene and Microbiology, University of W&#252;rzburg 
2Department of Biological Sciences, University of Alabama
to:
Leo M. Endres1 
Sarah F. Hathcock2 
Alexandra Schubert-Unkmeir1 
Brandon J. Kim1,2 
1Institute for Hygiene and Microbiology, University of W&#252;rzburg 
2Department of Biological Sciences, University of Alabama

An erratum was issued for:&#160;<a href="https://www.jove.com/t/61400">Neisseria meningitidis Infection of Induced Pluripotent Stem-Cell Derived Brain Endothelial Cells Larvae</a>. The Authors section was updated.

Erratum: Neisseria meningitidis Infection of Induced Pluripotent Stem-Cell Derived Brain Endothelial Cells

The blood-brain barrier (BBB), and the meningeal blood-CSF barrier (mBCSFB) are extremely tight cellular barriers that separate the circulation from the central nervous system (CNS) and are primarily comprised of highly specialized brain endothelial cells (BECs)1,2. Together, BECs maintain proper brain homeostasis by regulating nutrients and waste products in and out of the brain, while excluding many toxins, drugs, and pathogens1,2. Bacterial meningitis occurs when blood-borne bacteria are able to interact with, and penetrate the barrier formed by BECs and cause inflammation. Neisseria meningitidis (Nm, meningococcus) is a Gram-negative bacterium that colonizes the nasopharaynx of 10&#8210;40 % of healthy individuals, but in some cases can cause serious systemic disease3. In affected individuals, Nm can gain access to the blood stream where it can cause purpura fulminans as well as penetrate BECs gaining access to the CNS causing meningitis3. Nm is a leading cause of bacterial meningitis world-wide, and despite vaccination efforts, is still a primary cause of meningitis4. Modern medical intervention, such as antibiotic treatment, have made these conditions survivable, however those affected with meningitis often are left with permanent neurological damage5,6.
Previous studies have identified bacterial factors and host signaling that contribute to Nm-BEC interactions7,8,9,10,11. The identified adhesins and invasins such as the opacity protein Opc, and type-IV pili, as well as receptors such as CD147, have been conducted on various BEC models in vitro, however these models lack many defining BBB properties7,9,11,12. Complete understanding of Nm-BEC interactions remain elusive due partially to the inability to utilize in vivo models, incomplete vaccination protection, and lack of robust human BEC models in vitro.
Modeling hBECs in vitro has been challenging due to the unique properties of BECs. Compared with peripheral endothelial cells, BECs have a number of phenotypes that enhance their barrier properties such as high trans-endothelial electrical resistance (TEER) due to complex tight junctions12. Once removed from the brain microenvironment, BECs rapidly lose their barrier properties limiting the usefulness of primary or immortalized in vitro models that only form a weak barrier12,13. The combination of the human specificity of Nm infections, lack of robust in vivo models, and challenges modeling human BECs in vitro creates a need for better models to understand the complex host-pathogen interaction between Nm and BECs. Recently using model human&#160;induced pluripotent stem cell&#160;(iPSC) technologies BEC-like&#160;cells have been derived from&#160;iPSCs that better mimic BECs&#160;in vivo12,13,14,15. iPSC-BECs are of human origin, easily scalable, and possess expected BEC phenotypes compared to their primary or immortalized counterparts12,13,14,15. Additionally we and others have demonstrated that iPSC-BECs are useful for modeling various diseases of the CNS such as host-pathogen interaction, Huntington&#8217;s disease, and MCT8 deficiency that causes Allan-Hurndon-Dudley syndrome16,17,18,19,20,21. Here, we demonstrate how to derive iPSC-BECs from renewable iPSC sources and the infection of iPSC-BECs with Nm leading to activation of the innate immune response. We believe that this model is useful to interrogate host-pathogen interaction that is unable to be recapitulated in other in vitro models and is especially useful when examining interactions with human specific pathogens such as Nm.

<table border="0" cellpadding="0" cellspacing="0" style="width:1301px;" width="1300">
	<colgroup>
		<col />
		<col />
		<col />
		<col />
	</colgroup>
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:459px;">Accutase (1x)</td>
			<td style="width:216px;">Sigma</td>
			<td style="width:161px;">A6964</td>
			<td style="width:465px;">Enzymatic cell dissociation reagent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:459px;">Acetic acid</td>
			<td style="width:216px;">Sigma</td>
			<td style="width:161px;">A6283</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:459px;">All-trans retinoic acid (RA)</td>
			<td style="width:216px;">Sigma</td>
			<td style="width:161px;">R2625</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:459px;">Anti-CD31 (PECAM-1)</td>
			<td style="width:216px;">Thermo Scientific (Labvision)</td>
			<td style="width:161px;">RB-10333</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:459px;">Anti-Claudin-5</td>
			<td style="width:216px;">Invitrogen</td>
			<td style="width:161px;">4C3C2</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:459px;">Anti-Glut-1</td>
			<td style="width:216px;">Thermo Scientific (Labvision)</td>
			<td style="width:161px;">SPM498 (MA5-11315)</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:459px;">Anti-Occludin</td>
			<td style="width:216px;">Invitrogen</td>
			<td style="width:161px;">33-1500</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:459px;">Anti-VE-cadherin</td>
			<td style="width:216px;">Santa Cruz</td>
			<td style="width:161px;">sc-52751</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:459px;">Anti-ZO-1</td>
			<td style="width:216px;">Invitrogen</td>
			<td style="width:161px;">33-9100</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Bacto Proteose Peptone</td>
			<td style="width:216px;">BD</td>
			<td style="width:161px;">211684</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">b-Mercaptoethanol</td>
			<td style="width:216px;">Merck (Sigma-Aldrich)</td>
			<td style="width:161px;">805740</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:459px;">Cell culture plates and flasks</td>
			<td style="width:216px;">Sarstedt</td>
			<td style="width:161px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:459px;">Centrifuge (Heraeus Megafuge 1.0R)</td>
			<td style="width:216px;">Thermo Scientific</td>
			<td style="width:161px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:459px;">Class II biosafety cabinet</td>
			<td style="width:216px;">Nuaire</td>
			<td style="width:161px;">NU-437-400E</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:459px;">CO2 Incubator (DHD Autoflow CO2 Air-Jacketed Incubator)</td>
			<td style="width:216px;">Nuaire</td>
			<td style="width:161px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:459px;">Collagen IV</td>
			<td style="width:216px;">Sigma</td>
			<td style="width:161px;">C5533</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:459px;">Columbia ager + 5 % sheep blood</td>
			<td style="width:216px;">Biomerieux</td>
			<td style="width:161px;">43049</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:459px;">Costar Transwell polyester filters (12- or 24-well)</td>
			<td style="width:216px;">Corning</td>
			<td style="width:161px;">3460, 3470</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:459px;">D(+)-Glucose</td>
			<td style="width:216px;">Merck (Sigma-Aldrich)</td>
			<td style="width:161px;">G8270</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:459px;">DAPI</td>
			<td style="width:216px;">Invitrogen</td>
			<td style="width:161px;">D1306</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:459px;">DMEM/F12</td>
			<td style="width:216px;">Gibco</td>
			<td style="width:161px;">31330-038</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:459px;">DMSO</td>
			<td style="width:216px;">ROTH</td>
			<td style="width:161px;">A994.1</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:459px;">Dulbecco&#39;s phosphate-buffered saline (DPBS)</td>
			<td style="width:216px;">Gibco</td>
			<td style="width:161px;">21600-069</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:459px;">Epithelial Volt-Ohm Meter (Millicell ERS-2) with STX electrode</td>
			<td style="width:216px;">Merck (Millipore)</td>
			<td style="width:161px;">MERS00002</td>
			<td></td>
		</tr>
		<tr height="25">
			<td height="25" style="height:25px;width:459px;">Fe(NO3)3</td>
			<td style="width:216px;">ROTH</td>
			<td style="width:161px;">5632.1</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:459px;">Fibronectin</td>
			<td style="width:216px;">Sigma</td>
			<td style="width:161px;">F1141</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:459px;">Fluoresence microscope (Eclipse Ti)</td>
			<td style="width:216px;">Nikon</td>
			<td style="width:161px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:459px;">Hemacytometer (Neubauer)</td>
			<td style="width:216px;">A. Hartenstein</td>
			<td style="width:161px;">ZK06</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:459px;">Human basic fibroblast growth factor (bFGF)</td>
			<td style="width:216px;">PeproTech</td>
			<td style="width:161px;">100-18B</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:459px;">Human Endothelial Serum Free Medium (hESFM)</td>
			<td style="width:216px;">Gibco</td>
			<td style="width:161px;">11111-044</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:459px;">Inverted microscope (Wilovert)</td>
			<td style="width:216px;">Hund (Will Wetzlar)</td>
			<td style="width:161px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:459px;">iPS(IMR90)-4 cells</td>
			<td style="width:216px;">WiCell</td>
			<td style="width:161px;"></td>
			<td></td>
		</tr>
		<tr height="25">
			<td height="25" style="height:25px;width:459px;">Kellogg&#39;s supplement</td>
			<td style="width:216px;"></td>
			<td style="width:161px;"></td>
			<td>To prepare 110 ml of Kellogg&#39;s supplement, prepare 100 ml of 4 g/ml glucose, 0.1 g/ml glutamine, and 0.2 mg/ml thiamine pyrophosphate and 10 ml of 5 mg/ml Fe(NO3)3 and combine the solutions. Filter sterilize and store aliquoted at -20 &#176;C.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:459px;">Knockout serum replacement (KOSR)</td>
			<td style="width:216px;">Gibco</td>
			<td style="width:161px;">10828-028</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:459px;">L-glutamine (GlutaMAX)</td>
			<td style="width:216px;">Invitrogen</td>
			<td style="width:161px;">35050-038</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">LunaScript RT SuperMix Kit</td>
			<td style="width:216px;">NEB</td>
			<td style="width:161px;">E3010L</td>
			<td>cDNA synthesis kit</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:459px;">Matrigel Matrix</td>
			<td style="width:216px;">Corning</td>
			<td style="width:161px;">354230</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:459px;">Methanol</td>
			<td style="width:216px;">ROTH</td>
			<td style="width:161px;">4627.5</td>
			<td></td>
		</tr>
		<tr height="25">
			<td height="25" style="height:25px;">MgCl2</td>
			<td style="width:216px;">ROTH</td>
			<td style="width:161px;">KK36.1</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:459px;">Micropipettes (Research Plus)</td>
			<td style="width:216px;">Eppendorf</td>
			<td style="width:161px;"></td>
			<td></td>
		</tr>
		<tr height="25">
			<td height="25" style="height:25px;">NaHCO3</td>
			<td style="width:216px;">ROTH</td>
			<td style="width:161px;">6329</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:459px;">Nonessential amino acids (NEAA)</td>
			<td style="width:216px;">Gibco</td>
			<td style="width:161px;">11140-035</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">NucleoSpin RNA isolation kit</td>
			<td>Machery-Nagel</td>
			<td style="width:161px;">740955</td>
			<td>RNA isolation kit</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:459px;">Pipette boy (Accu-Jet Pro)</td>
			<td style="width:216px;">Brand</td>
			<td style="width:161px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:459px;">Platelet poor plasma-derived serum, bovine (PDS)</td>
			<td style="width:216px;">Fisher</td>
			<td style="width:161px;">50-443-029</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">PowerUp SYBR Green Master Mix</td>
			<td>Applied Biosystems</td>
			<td style="width:161px;">A25742</td>
			<td>qPCR master mix</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:459px;">qPCR film (MicroAmp Optical Adhesive Film)</td>
			<td style="width:216px;">Applied Biosystems</td>
			<td style="width:161px;">4211971</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:459px;">qPCR plates (MicroAmp Fast 96-well)</td>
			<td style="width:216px;">Applied Biosystems</td>
			<td style="width:161px;">4346907</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:459px;">ROCK inhibitor, Y27632 dihydrochloride</td>
			<td style="width:216px;">Tocris</td>
			<td style="width:161px;">1254</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:459px;">RT-PCR thermo cycler (StepOnePlus)</td>
			<td style="width:216px;">Applied Biosystems</td>
			<td style="width:161px;">4376600</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:459px;">Serological pipettes</td>
			<td style="width:216px;">Sarstedt</td>
			<td style="width:161px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:459px;">StemFlex basal medium + 50x StemFlex supplement</td>
			<td style="width:216px;">Gibco</td>
			<td>A3349401</td>
			<td>Stem-cell maintenance medium</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:459px;">Swinging Bucket Rotor (Heraeus #2704)</td>
			<td style="width:216px;">Thermo Scientific</td>
			<td style="width:161px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:459px;">Thiamine pyrophosphate</td>
			<td style="width:216px;">Sigma</td>
			<td style="width:161px;">C8754-5G</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:459px;">Trypan Blue Solution, 0.4%</td>
			<td style="width:216px;">Gibco</td>
			<td style="width:161px;">15250061</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:459px;">Versene</td>
			<td style="width:216px;">Gibco</td>
			<td style="width:161px;">15040-033</td>
			<td>Non-enzymatic cell dissociation reagent (EDTA)</td>
		</tr>
	</tbody>
</table>

neisseria meningitidis infection of induced pluripotent stem-cell derived brain endothelial cells

Meningococcal meningitis is a life-threatening infection that occurs when Neisseria meningitidis (meningococcus, Nm) can gain access to the central nervous system (CNS) by penetrating highly specialized brain endothelial cells (BECs). As Nm is a human-specific pathogen, the lack of robust in vivo model systems makes study of the host-pathogen interactions between Nm and BECs challenging and establishes a need for a human based model that mimics native BECs. BECs possess tighter barrier properties when compared to peripheral endothelial cells characterized by complex tight junctions and elevated trans-endothelial electrical resistance (TEER). However, many in vitro models, such as primary BECs and immortalized BECs, either lack or rapidly lose their barrier properties after removal from the native neural microenvironment. Recent advances in human stem-cell technologies have developed methods for deriving brain-like endothelial cells from induced pluripotent stem-cells (iPSCs) that better phenocopy BECs when compared to other in vitro human models. The use of iPSC-derived BECs (iPSC-BECs) to model Nm-BEC interaction has the benefit of using human cells that possess BEC barrier properties, and can be used to examine barrier destruction, innate immune activation, and bacterial interaction. Here we demonstrate how to derive iPSC-BECs from iPSCs in addition to bacterial preparation, infection, and sample collection for analysis.

The protocol described here is adapted from Stebbins et al. and highlights the process to differentiate iPSCs into brain-like endothelial cells that possess BBB properties, and how to utilize this model for infection studies using iPSC-BECs with Nm19,22. The iPSC-BECs, when differentiated properly, exhibit tight barrier properties measured by TEER that are often greater than 2000 &#937;&#183;cm2, and express endothelial markers such as VE-cadherin and ...

Watch this Scientific Journal Video about Neisseria meningitidis Infection of Induced Pluripotent Stem-Cell Derived Brain Endothelial Cells at JoVE.com

Neisseria meningitidis Infection of Induced Pluripotent Stem-Cell Derived Brain Endothelial Cells

The protocol described here highlights the major steps in the differentiating induced pluripotent stem-cell derived brain-like endothelial cells, the preparation of Neisseria meningitidis for infection, and sample collection for other molecular analyses.

Neisseria meningitidis Infection of Induced Pluripotent Stem-Cell Derived Brain Endothelial Cells

Meningococcal meningitis is a life-threatening infection that occurs when Neisseria meningitidis (meningococcus, Nm) can gain access to the central ...

neisseria-meningitidis-infection-induced-pluripotent-stem-cell

Research

JoVE Journal

Immunology and Infection

2.3K Views.  University of Würzburg. The protocol described here highlights the major steps in the differentiating induced pluripotent stem-cell derived brain-like endothelial cells, the preparation of Neisseria meningitidis for infection, and sample collection for other molecular analyses.

Video: Neisseria meningitidis Infection of Induced Pluripotent Stem-Cell Derived Brain Endothelial Cells

Visualisation and Quantification of Intracellular Interactions of Neisseria meningitidis and Human &alpha;-actinin by Confocal Imaging

The Opc protein of Neisseria meningitidis (Nm, meningococcus) is a surface-expressed integral outer membrane protein, which can act as an adhesin and an effective invasin for human epithelial and endothelial cells. We have identified endothelial surface-located integrins as major receptors for Opc, a process which requires Opc to first bind to integrin ligands such as vitronectin and via these to the cell-expressed receptors1. This process leads to bacterial invasion of endothelial cells2. More recently, we observed an interaction of Opc with a 100kDa protein found in whole cell lysates of human cells3. We initially observed this interaction when host cell proteins separated by electrophoresis and blotted on to nitrocellulose were overlaid with Opc-expressing Nm. The interaction was direct and did not involve intermediate molecules. By mass spectrometry, we established the identity of the protein as &alpha;-actinin. As no surface expressed &alpha;-actinin was found on any of the eight cell lines examined, and as Opc interactions with endothelial cells in the presence of serum lead to bacterial entry into the target cells, we examined the possibility of the two proteins interacting intracellularly. For this, cultured human brain microvascular endothelial cells (HBMECs) were infected with Opc-expressing Nm for extended periods and the locations of internalised bacteria and &alpha;-actinin were examined by confocal microscopy. We observed time-dependent increase in colocalisation of Nm with the cytoskeletal protein, which was considerable after an eight hour period of bacterial internalisation. In addition, the use of quantitative imaging software enabled us to obtain a relative measure of the colocalisation of Nm with &alpha;-actinin and other cytoskeletal proteins. Here we present a protocol for visualisation and quantification of the colocalisation of the bacterium with intracellular proteins after bacterial entry into human endothelial cells, although the procedure is also applicable to human epithelial cells.

Visualisation and Quantification of Intracellular Interactions of Neisseria meningitidis and Human &amp;#945;-actinin by Confocal Imaging

Neisseria meningitidis (Nm), a gram negative human-specific respiratory pathogen, can bind to human &alpha;-actinin. Here we present a protocol for visualisation of colocalisation of the bacterium with intracellular &alpha;-actinin after bacterial entry into human brain microvascular endothelial cells (HBMECs).

The Opc protein of Neisseria meningitidis (Nm, meningococcus) is a surface-expressed integral outer membrane protein, which can act as an adhesin and an ...

Selection of Plasmodium falciparum Parasites for Cytoadhesion to Human Brain Endothelial Cells

Most human malaria deaths are caused by blood-stage Plasmodium falciparum parasites. Cerebral malaria, the most life-threatening complication of the disease, is characterised by an accumulation of Plasmodium falciparum infected red blood cells (iRBC) at pigmented trophozoite stage in the microvasculature of the brain2-4. This microvessel obstruction (sequestration) leads to acidosis, hypoxia and harmful inflammatory cytokines (reviewed in 5). Sequestration is also found in most microvascular tissues of the human body2, 3. The mechanism by which iRBC attach to the blood vessel walls is still poorly understood.
The immortalized Human Brain microvascular Endothelial Cell line (HBEC-5i) has been used as an in vitro model of the blood-brain barrier6. However, Plasmodium falciparum iRBC attach only poorly to HBEC-5i in vitro, unlike the dense sequestration that occurs in cerebral malaria cases. We therefore developed a panning assay to select (enrich) various P. falciparum strains for adhesion to HBEC-5i in order to obtain populations of high-binding parasites, more representative of what occurs in vivo.
A sample of a parasite culture (mixture of iRBC and uninfected RBC) at the pigmented trophozoite stage is washed and incubated on a layer of HBEC-5i grown on a Petri dish. After incubation, the dish is gently washed free from uRBC and unbound iRBC. Fresh uRBC are added to the few iRBC attached to HBEC-5i and incubated overnight. As schizont stage parasites burst, merozoites reinvade RBC and these ring stage parasites are harvested the following day. Parasites are cultured until enough material is obtained (typically 2 to 4 weeks) and a new round of selection can be performed. Depending on the P. falciparum strain, 4 to 7 rounds of selection are needed in order to get a population where most parasites bind to HBEC-5i. The binding phenotype is progressively lost after a few weeks, indicating a switch in variant surface antigen gene expression, thus regular selection on HBEC-5i is required to maintain the phenotype.
In summary, we developed a selection assay rendering P. falciparum parasites a more "cerebral malaria adhesive" phenotype. We were able to select 3 out of 4 P. falciparum strains on HBEC-5i. This assay has also successfully been used to select parasites for binding to human dermal and pulmonary endothelial cells. Importantly, this method can be used to select tissue-specific parasite populations in order to identify candidate parasite ligands for binding to brain endothelium. Moreover, this assay can be used to screen for putative anti-sequestration drugs7.

Selection of Plasmodium falciparum Parasites for Cytoadhesion to Human Brain Endothelial Cells

An in vitro model for cerebral malaria sequestration is described1. Plasmodium falciparum infected red blood cells are selected for binding to immortalized human brain microvascular endothelial cells. The selected parasites show a distinct phenotype. The selection process can be applied using various P. falciparum strains and endothelial cell lines.

Most human malaria deaths are caused by blood-stage Plasmodium falciparum parasites. Cerebral malaria, the most life-threatening complication of the ...

Directed Differentiation of Induced Pluripotent Stem Cells towards T Lymphocytes

Adoptive cell transfer (ACT) of antigen-specific CD8+ cytotoxic T lymphocytes (CTLs) is a promising treatment for a variety of malignancies 1. CTLs can recognize malignant cells by interacting tumor antigens with the T cell receptors (TCR), and release cytotoxins as well as cytokines to kill malignant cells. It is known that less-differentiated and central-memory-like (termed highly reactive) CTLs are the optimal population for ACT-based immunotherapy, because these CTLs have a high proliferative potential, are less prone to apoptosis than more differentiated cells and have a higher ability to respond to homeostatic cytokines 2-7. However, due to difficulties in obtaining a high number of such CTLs from patients, there is an urgent need to find a new approach to generate highly reactive Ag-specific CTLs for successful ACT-based therapies.
TCR transduction of the self-renewable stem cells for immune reconstitution has a therapeutic potential for the treatment of diseases 8-10. However, the approach to obtain embryonic stem cells (ESCs) from patients is not feasible. Although the use of hematopoietic stem cells (HSCs) for therapeutic purposes has been widely applied in clinic 11-13, HSCs have reduced differentiation and proliferative capacities, and HSCs are difficult to expand in in vitro cell culture 14-16. Recent iPS cell technology and the development of an in vitro system for gene delivery are capable of generating iPS cells from patients without any surgical approach. In addition, like ESCs, iPS cells possess indefinite proliferative capacity in vitro, and have been shown to differentiate into hematopoietic cells. Thus, iPS cells have greater potential to be used in ACT-based immunotherapy compared to ESCs or HSCs.
Here, we present methods for the generation of T lymphocytes from iPS cells in vitro, and in vivo programming of antigen-specific CTLs from iPS cells for promoting cancer immune surveillance. Stimulation in vitro with a Notch ligand drives T cell differentiation from iPS cells, and TCR gene transduction results in iPS cells differentiating into antigen-specific T cells in vivo, which prevents tumor growth. Thus, we demonstrate antigen-specific T cell differentiation from iPS cells. Our studies provide a potentially more efficient approach for generating antigen-specific CTLs for ACT-based therapies and facilitate the development of therapeutic strategies for diseases.

Generation of T lymphocytes from induced pluripotent stem (iPS) cells gives an alternative approach of using embryonic stem cells for T cell-based immunotherapy. The method shows that by utilizing either in vitro or in vivo induction system, iPS cells are able to differentiate into both conventional and antigen-specific T lymphocytes.

Adoptive cell transfer (ACT) of antigen-specific CD8+  cytotoxic T lymphocytes (CTLs) is a promising treatment for a variety of  malignancies 1. CTLs can  ...

Development of Stem Cell-derived Antigen-specific Regulatory T Cells Against Autoimmunity

Autoimmune diseases arise due to the loss of immunological self-tolerance. Regulatory T cells (Tregs) are important mediators of immunologic self-tolerance. Tregs represent about 5 - 10% of the mature CD4+ T cell subpopulation in mice and humans, with about 1 - 2% of those Tregs circulating in the peripheral blood. Induced pluripotent stem cells (iPSCs) can be differentiated into functional Tregs, which have a potential to be used for cell-based therapies of autoimmune diseases. Here, we present a method to develop antigen (Ag)-specific Tregs from iPSCs (i.e., iPSC-Tregs). The method is based on incorporating the transcription factor FoxP3 and an Ag-specific T cell receptor (TCR) into iPSCs and then differentiating on OP9 stromal cells expressing Notch ligands delta-like (DL) 1 and DL4. Following in vitro differentiation, the iPSC-Tregs express CD4, CD8, CD3, CD25, FoxP3, and Ag-specific TCR and are able to respond to Ag stimulation. This method has been successfully applied to cell-based therapy of autoimmune arthritis in a murine model. Adoptive transfer of these Ag-specific iPSC-Tregs into Ag-induced arthritis (AIA)-bearing mice has the ability to reduce joint inflammation and swelling and to prevent bone loss.

We present here a method to develop functional antigen (Ag)-specific regulatory T cells (Tregs) from induced pluripotent stem cells (iPSCs) for immunotherapy of autoimmune arthritis in a murine model.

Autoimmune diseases arise due to the loss of immunological self-tolerance. Regulatory T cells (Tregs) are important mediators of immunologic ...

Using Human Induced Pluripotent Stem Cell-derived Intestinal Organoids to Study and Modify Epithelial Cell Protection Against Salmonella and Other Pathogens

The intestinal &#8216;organoid&#8217; (iHO) system, wherein 3-D structures representative of the epithelial lining of the human gut can be produced from human induced pluripotent stem cells (hiPSCs) and maintained in culture, provides an exciting opportunity to facilitate the modeling of the epithelial response to enteric infections. In vivo, intestinal epithelial cells (IECs) play a key role in regulating intestinal homeostasis and may directly inhibit pathogens, although the mechanisms by which this occurs are not fully elucidated. The cytokine interleukin-22 (IL-22) has been shown to play a role in the maintenance and defense of the gut epithelial barrier, including inducing a release of antimicrobial peptides and chemokines in response to infection.
We describe the differentiation of healthy control hiPSCs into iHOs via the addition of specific cytokine combinations to their culture medium before embedding them into a basement membrane matrix-based prointestinal culture system. Once embedded, the iHOs are grown in media supplemented with Noggin, R-spondin-1, epidermal growth factor (EGF), CHIR99021, prostaglandin E2, and Y-27632 dihydrochloride monohydrate. Weekly passages by manual disruption of the iHO ultrastructure lead to the formation of budded iHOs, with some exhibiting a crypt/villus structure. All iHOs demonstrate a differentiated epithelium consisting of goblet cells, enteroendocrine cells, Paneth cells, and polarized enterocytes, which can be confirmed via immunostaining for specific markers of each cell subset, transmission electron microscopy (TEM), and quantitative PCR (qPCR). To model infection, Salmonella enterica serovar Typhimurium SL1344 are microinjected into the lumen of the iHOs and incubated for 90 min at 37 &#176;C, and a modified gentamicin protection assay is performed to identify the levels of intracellular bacterial invasion. Some iHOs are also pretreated with recombinant human IL-22 (rhIL-22) prior to infection to establish whether this cytokine is protective against Salmonella infection.

Using Human Induced Pluripotent Stem Cell-derived Intestinal Organoids to Study and Modify Epithelial Cell Protection Against Salmonella and Other Pathogens

Human induced pluripotent stem cell (hiPSC)-derived intestinal organoids offer exciting opportunities to model enteric diseases in vitro. We demonstrate the differentiation of hiPSCs into intestinal organoids (iHOs), the stimulation of these iHOs with cytokines, and the microinjection of Salmonella Typhimurium into the iHO lumen, enabling the study of an epithelial invasion by this pathogen.

The intestinal &#8216;organoid&#8217; (iHO) system, wherein 3-D structures representative of the epithelial lining of the human gut can be produced from ...

Induced Differentiation of M Cell-like Cells in Human Stem Cell-derived Ileal Enteroid Monolayers

M (microfold) cells of the intestine function to transport antigen from the apical lumen to the underlying Peyer&#8217;s patches and lamina propria where immune cells reside and therefore contribute to mucosal immunity in the intestine. A complete understanding of how M cells differentiate in the intestine as well as the molecular mechanisms of antigen uptake by M cells is lacking. This is because M cells are a rare population of cells in the intestine and because in vitro models for M cells are not robust. The discovery of a self-renewing stem cell culture system of the intestine, termed enteroids, has provided new possibilities for culturing M cells. Enteroids are advantageous over standard cultured cell lines because they can be differentiated into several major cell types found in the intestine, including goblet cells, Paneth cells, enteroendocrine cells and enterocytes. The cytokine RANKL is essential in M cell development, and addition of RANKL and TNF-&#945; to culture media promotes a subset of cells from ileal enteroids to differentiate into M cells. The following protocol describes a method for the differentiation of M cells in a transwell epithelial polarized monolayer system of the intestine using human ileal enteroids. This method can be applied to the study of M cell development and function.

This protocol describes how to induce the differentiation of M cells in human stem cell-derived ileal monolayers and methods to assess their development.

M (microfold) cells of the intestine function to transport antigen from the apical lumen to the underlying Peyer&#8217;s patches and lamina propria where ...

Stem Cell-Derived Viral Ag-Specific T Lymphocytes Suppress HBV Replication in Mice

Hepatitis B virus (HBV) infection is a global health issue. With over 350 million people affected worldwide, HBV infection remains the leading cause of liver cancer. This is a major concern, especially in developing countries. Failure of the immune system to mount an effective response against HBV leads to chronic infection. Although HBV vaccine is present and novel antiviral medicines are being created, eradication of virus-reservoir cells remains a major health topic. Described here is a method for the generation of viral antigen (Ag) -specific CD8+ cytotoxic T lymphocytes (CTLs) derived from induced pluripotent stem cells (iPSCs) (i.e., iPSC-CTLs), which have the ability to suppress HBV replication. HBV replication is efficiently induced in mice through hydrodynamic injection of an HBV expression plasmid, pAAV/HBV1.2, into the liver. Then, HBV surface Ag-specific mouse iPSC-CTLs are adoptively transferred, which greatly suppresses HBV replication in the liver and blood as well as prevents HBV surface Ag expression in hepatocytes. This method demonstrates HBV replication in mice after hydrodynamic injection and that stem cell-derived viral Ag-specific CTLs can suppress HBV replication. This protocol provides a useful method for HBV immunotherapy.

Presented here is a protocol for the effective suppression of hepatitis B virus (HBV) replication in mice by utilizing adoptive cell transfer (ACT) of stem cell-derived viral antigen (Ag)-specific T lymphocytes. This procedure may be adapted for potential ACT-based immunotherapy of HBV infection.

Hepatitis B virus (HBV) infection is a global health issue. With over 350 million people affected worldwide, HBV infection remains the leading cause of ...

Pneumococcus Infection of Primary Human Endothelial Cells in Constant Flow

Interaction of Streptococcus pneumoniae with the surface of endothelial cells is mediated in blood flow via mechanosensitive proteins such as the Von Willebrand Factor (VWF). This glycoprotein changes its molecular conformation in response to shear stress, thereby exposing binding sites for a broad spectrum of host-ligand interactions. In general, culturing of primary endothelial cells under a defined shear flow is known to promote the specific cellular differentiation and the formation of a stable and tightly linked endothelial layer resembling the physiology of the inner lining of a blood vessel. Thus, the functional analysis of interactions between bacterial pathogens and the host vasculature involving mechanosensitive proteins requires the establishment of pump systems that can simulate the physiological flow forces known to affect the surface of vascular cells.
The microfluidic device used in this study enables a continuous and pulseless recirculation of fluids with a defined flow rate. The computer-controlled air-pressure pump system applies a defined shear stress on endothelial cell surfaces by generating a continuous, unidirectional, and controlled medium flow. Morphological changes of the cells and bacterial attachment can be microscopically monitored and quantified in the flow by using special channel slides that are designed for microscopic visualization. In contrast to static cell culture infection, which in general requires a sample fixation prior to immune labeling and microscopic analyses, the microfluidic slides enable both the fluorescence-based detection of proteins, bacteria, and cellular components after sample fixation; serial immunofluorescence staining; and direct fluorescence-based detection in real time. In combination with fluorescent bacteria and specific fluorescence-labeled antibodies, this infection procedure provides an efficient multiple component visualization system for a huge spectrum of scientific applications related to vascular processes.

This study describes the microscopic monitoring of pneumococcus adherence to von Willebrand factor strings produced on the surface of differentiated human primary endothelial cells under shear stress in defined flow conditions. This protocol can be extended to detailed visualization of specific cell structures and quantification of bacteria by applying differential immunostaining procedures.

Interaction of Streptococcus pneumoniae with the surface of endothelial cells is mediated in blood flow via mechanosensitive proteins such as the Von ...

Analyzing the Permeability of the Blood-Brain Barrier by Microbial Traversal through Microvascular Endothelial Cells

The human blood-brain barrier (BBB) is characterized by a very low permeability for biomolecules in order to protect and regulate the metabolism of the brain. The BBB is mainly formed out of endothelial cells embedded in collagen IV and fibronectin-rich basement membranes. Several pathologies result from dysfunction of the BBB followed by microbial traversal, causing diseases such as meningitis. In order to test the effect of multiple parameters, including different drugs and anesthetics, on the permeability of the BBB we established a novel human cell culture model mimicking the BBB with human brain microvascular endothelial cells. The endothelial cells are grown on collagen IV and fibronectin-coated filter units until confluence and can then be treated with different compounds of interest. In order to demonstrate a microbial traversal, the upper chamber with the apical surface of the endothelial cells is inoculated with bacteria. After an incubation period, samples of the lower chamber are plated on agar plates and the obtained colonies are counted, whereby the number of colonies correlate with the permeability of the BBB. Endogenous cellular factors can be analyzed in this experimental set-up in order to elucidate basic cellular mechanisms of the endothelial cells contributing to the BBB. In addition, this platform allows performing a screen for compounds that might affect the permeability of the endothelial cells. Finally, bacterial traversal can be studied and linked to different pathologies, such as meningitis. It might be possible to extend the model and analyze the pathways of the bacteria through the BBB. In this article, we provide a detailed protocol of the described method to investigate the permeability of the BBB.

The human blood-brain barrier selectively prevents penetration of hydrophilic molecules and pathogens into the brain. Several pathologies, including meningitis and postoperative delirium, are associated with an increased permeability of the blood-brain barrier. Here, we describe an endothelial cell culture model to test the barrier permeability by microbial traversal.

The human blood-brain barrier (BBB) is characterized by a very low permeability for biomolecules in order to protect and regulate the metabolism of the ...

Isolation of Primary Mouse Lung Endothelial Cells

Endothelial cells play critical roles in the regulation of vascular tone, immunity, coagulation, and permeability. Endothelial dysfunction occurs in medical conditions including diabetes, atherosclerosis, sepsis, and acute lung injury. A reliable and reproducible method to isolate pure endothelial cells from mice is needed to investigate the role of endothelial cells in the pathogenesis of these and other conditions. In this protocol, lung microvascular endothelial cells were prepared from 5-7 day old neonatal mouse pups. Lungs are harvested, minced, and enzymatically digested with collagenase I, and released cells are cultured overnight. Endothelial cells are then selected using anti-PECAM1 (CD-31) IgG conjugated to magnetic beads, and cells again are cultured to confluence. A secondary cell selection then occurs with anti-ICAM2 (CD-102) IgG conjugated to magnetic beads to increase the purity of the endothelial cells, and the cells again are cultured to confluence. The entire process takes approximately 7-10 days before the cells can be used for experimentation. This simple protocol yields highly pure (purity &#62;92%) endothelial cells that can be immediately used for in vitro studies, including the studies focused on endothelial cytokine and chemokine production, leukocyte-endothelial interactions, endothelial coagulation pathways, and endothelial permeability. With many knockouts and transgenic mouse lines available, this procedure also lends itself to understanding the function of specific genes expressed by endothelial cells in healthy and pathologic responses to injury, infection, and inflammation.

In this article, primary lung endothelial cells were isolated and cultured from neonatal mice.

Endothelial cells play critical roles in the regulation of vascular tone, immunity, coagulation, and permeability. Endothelial dysfunction occurs in ...