{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,14]],"date-time":"2026-07-14T15:33:16Z","timestamp":1784043196786,"version":"3.55.0"},"reference-count":39,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2024,12,18]],"date-time":"2024-12-18T00:00:00Z","timestamp":1734480000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000038","name":"National Science and Engineering Research Council of Canada (NSERC)","doi-asserted-by":"publisher","award":["RGPIN-2020-07020"],"award-info":[{"award-number":["RGPIN-2020-07020"]}],"id":[{"id":"10.13039\/501100000038","id-type":"DOI","asserted-by":"publisher"}]},{"name":"MITACS Globalink program","award":["RGPIN-2020-07020"],"award-info":[{"award-number":["RGPIN-2020-07020"]}]},{"name":"NSERC graduate scholarship","award":["RGPIN-2020-07020"],"award-info":[{"award-number":["RGPIN-2020-07020"]}]},{"name":"CMC Microsystems and the Digital Research Alliance of Canada","award":["RGPIN-2020-07020"],"award-info":[{"award-number":["RGPIN-2020-07020"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Micromachines"],"abstract":"<jats:p>The placenta plays a critical role in nutrient and oxygen exchange during pregnancy, yet the effects of medicinal drugs on this selective barrier remain poorly understood. To overcome this, this study presents a cost-effective bioimpedance spectroscopy (BIS) system to assess tight junction integrity and monolayer formation in BeWo b30 cells, a widely used model of the multinucleated maternal\u2013fetal exchange surface of the placental barrier. Cells were cultured on collagen-coated porous membranes and treated with forskolin to induce controlled syncytialization. Electrical impedance was measured using an entry level impedance analyzer, while immunofluorescence staining was used to confirm monolayer formation and syncytialization. The measurements and staining confirmed the formation of a confluent monolayer on day 4. In fact, the electrical resistance tripled for treated samples indicating a more electrically restrictive barrier. This resistance remained constant for treated samples reflecting the intact barrier\u2019s integrity over the next 3 days. The measurements show that, on day 4, the electrical capacitance of the cells decreased for the treated samples as opposed to the untreated samples. This reflects that the surface area of the BeWo b30 cells decreased when the samples were treated with forskolin. Finally, a COMSOL model was developed to explore the effects of electrode positioning, depth, and distance on TEER measurements, explaining discrepancies in the literature. In fact, there was a substantial 97% and 39.4% difference in the obtained TEER values. This study demonstrates the AD2 device\u2019s feasibility for monitoring placental barrier integrity and emphasizes the need for standardized setups for comparable results. The system can hence be used to analyze drug effects and nutrient transfer across the placental barrier.<\/jats:p>","DOI":"10.3390\/mi15121506","type":"journal-article","created":{"date-parts":[[2024,12,18]],"date-time":"2024-12-18T03:40:56Z","timestamp":1734493256000},"page":"1506","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Cost-Effective Bioimpedance Spectroscopy System for Monitoring Syncytialization In Vitro: Experimental and Numerical Validation of BeWo Cell Fusion"],"prefix":"10.3390","volume":"15","author":[{"given":"Karim","family":"Saad\u00e9","sequence":"first","affiliation":[{"name":"Department of Mechanical Engineering, University of Ottawa, Ottawa, ON K1N 6N5, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-6034-4727","authenticated-orcid":false,"given":"Mohammed Areeb","family":"Hussain","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, University of Ottawa, Ottawa, ON K1N 6N5, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8947-8152","authenticated-orcid":false,"given":"Shannon A.","family":"Bainbridge","sequence":"additional","affiliation":[{"name":"Faculty of Health Sciences, University of Ottawa, Ottawa, ON K1S 5S9, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Raphael","family":"St-Gelais","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, University of Ottawa, Ottawa, ON K1N 6N5, Canada"},{"name":"Department of Physics, University of Ottawa, Ottawa, ON K1N 6N5, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5519-6915","authenticated-orcid":false,"given":"Fabio","family":"Variola","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, University of Ottawa, Ottawa, ON K1N 6N5, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0958-671X","authenticated-orcid":false,"given":"Marianne","family":"Fenech","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, University of Ottawa, Ottawa, ON K1N 6N5, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,12,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"3065","DOI":"10.1039\/C6LC00259E","article-title":"A microphysiological model of the human placental barrier","volume":"16","author":"Blundell","year":"2016","journal-title":"Lab A Chip"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Burton, G.J., and Fowden, A.L. (2015). The placenta: A multifaceted, transient organ. Philos. Trans. R. Soc. B Biol. Sci., 370.","DOI":"10.1098\/rstb.2014.0066"},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Rothbauer, M., Patel, N., Gondola, H., Siwetz, M., Huppertz, B., and Ertl, P. (2017). A comparative study of five physiological key parameters between four different human trophoblast-derived cell lines. Sci. Rep., 7.","DOI":"10.1038\/s41598-017-06364-z"},{"key":"ref_4","unstructured":"Wong, M.K. (2020). The Design and Characterization of Microphysiological Platforms to Model the Human Placenta. [Doctoral Dissertation, McMaster University]."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"e12834","DOI":"10.1111\/aji.12834","article-title":"Forskolin-mediated BeWo cell fusion involves down-regulation of miR-92a-1-5p that targets dysferlin and protein kinase cAMP-activated catalytic subunit alpha","volume":"79","author":"Dubey","year":"2018","journal-title":"Am. J. Reprod. Immunol."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"1800112","DOI":"10.1002\/gch2.201800112","article-title":"Placenta-on-a-Chip: In Vitro Study of Caffeine Transport across Placental Barrier Using Liquid Chromatography Mass Spectrometry","volume":"3","author":"Pemathilaka","year":"2019","journal-title":"Glob. Chall."},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Elzinga, F.A., Khalili, B., Touw, D.J., Prins, J.R., Olinga, P., Leuvenink, H.G.D., Van Goor, H., Gordijn, S.J., Nagelkerke, A., and Mian, P. (2023). Placenta-on-a-Chip as an In Vitro Approach to Evaluate the Physiological and Structural Characteristics of the Human Placental Barrier upon Drug Exposure: A Systematic Review. J. Clin. Med., 12.","DOI":"10.3390\/jcm12134315"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"287","DOI":"10.1007\/s10928-020-09687-z","article-title":"Challenges in conducting clinical research studies in pregnant women","volume":"47","author":"McKiever","year":"2020","journal-title":"J. Pharmacokinet. Pharmacodyn."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"56","DOI":"10.1016\/j.jri.2014.10.004","article-title":"Are animal models useful or confusing in understanding the human feto-maternal relationship? A debate","volume":"108","author":"Chaouat","year":"2015","journal-title":"J. Reprod. Immunol."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"65","DOI":"10.1016\/j.jri.2015.03.001","article-title":"Only humans have human placentas: Molecular differences between mice and humans","volume":"108","author":"Schmidt","year":"2015","journal-title":"J. Reprod. Immunol."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"70","DOI":"10.1016\/j.placenta.2021.09.011","article-title":"The road (not) taken\u2014Placental transfer and interspecies differences","volume":"115","author":"Schmidt","year":"2021","journal-title":"Placenta"},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Bongaerts, E., Aengenheister, L., Dugershaw, B.B., Manser, P., Roeffaers, M.B.J., Ameloot, M., Nawrot, T.S., Bov\u00e9, H., and Buerki-Thurnherr, T. (2021). Label-free detection of uptake, accumulation, and translocation of diesel exhaust particles in ex vivo perfused human placenta. J. Nanobiotechnology, 19.","DOI":"10.1186\/s12951-021-00886-5"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"84","DOI":"10.1093\/bjaceaccp\/mku013","article-title":"Placental structure, function and drug transfer","volume":"15","author":"Griffiths","year":"2015","journal-title":"Contin. Educ. Anaesth. Crit. Care Pain"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"1559","DOI":"10.1007\/s00436-019-06257-2","article-title":"Susceptibility of human villous (BeWo) and extravillous (HTR-8\/SVneo) trophoblast cells to Toxoplasma gondii infection is modulated by intracellular iron availability","volume":"118","author":"Almeida","year":"2019","journal-title":"Parasitol. Res."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"1822","DOI":"10.1039\/d0mt00199f","article-title":"Human placental cell line HTR-8\/SVneo accumulates cadmium by divalent metal transporters DMT1 and ZIP14","volume":"12","author":"Widhalm","year":"2020","journal-title":"Metallomics"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"140","DOI":"10.1016\/j.biomaterials.2018.08.025","article-title":"In vitro placenta barrier model using primary human trophoblasts, underlying connective tissue and vascular endothelium","volume":"192","author":"Nishiguchi","year":"2019","journal-title":"Biomaterials"},{"key":"ref_17","doi-asserted-by":"crossref","unstructured":"Cherubini, M., Erickson, S., and Haase, K. (2021). Modelling the Human Placental Interface In Vitro\u2014A Review. Micromachines, 12.","DOI":"10.3390\/mi12080884"},{"key":"ref_18","doi-asserted-by":"crossref","unstructured":"Kreuder, A.-E., Bola\u00f1os-Rosales, A., Palmer, C., Thomas, A., Geiger, M.-A., Lam, T., Amler, A.-K., Markert, U.R., Lauster, R., and Kloke, L. (2020). Inspired by the human placenta: A novel 3D bioprinted membrane system to create barrier models. Sci. Rep., 10.","DOI":"10.1038\/s41598-020-72559-6"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"C1596","DOI":"10.1152\/ajpcell.1997.273.5.C1596","article-title":"Permeability properties of monolayers of the human trophoblast cell line BeWo","volume":"273","author":"Liu","year":"1997","journal-title":"Am. J. Physiol.-Cell Physiol."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"204","DOI":"10.1006\/excr.1993.1139","article-title":"Establishment and Characterization of First Trimester Human Trophoblast Cells with Extended Lifespan","volume":"206","author":"Graham","year":"1993","journal-title":"Exp. Cell Res."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"59","DOI":"10.1007\/BF02628263","article-title":"Glycogen metabolism in human hormone-producing trophoblastic cells in continuous culture","volume":"7","author":"Pattillo","year":"1971","journal-title":"In Vitro"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"683","DOI":"10.1210\/jcem-32-5-683","article-title":"Isolation of Hormone-Producing Clonal Lines of Human Choriocarcinoma1","volume":"32","author":"Kohler","year":"1971","journal-title":"J. Clin. Endocrinol. Metab."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"77","DOI":"10.3181\/00379727-102-25149","article-title":"Choriocarcinoma of Women Maintained in Serial Passage in Hamster and Rat","volume":"102","author":"Hertz","year":"1959","journal-title":"Exp. Biol. Med."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"107","DOI":"10.1177\/2211068214561025","article-title":"TEER Measurement Techniques for In Vitro Barrier Model Systems","volume":"20","author":"Srinivasan","year":"2015","journal-title":"SLAS Technol."},{"key":"ref_25","doi-asserted-by":"crossref","unstructured":"Ferrari, E., Palma, C., Vesentini, S., Occhetta, P., and Rasponi, M. (2020). Integrating Biosensors in Organs-on-Chip Devices: A Perspective on Current Strategies to Monitor Microphysiological Systems. Biosensors, 10.","DOI":"10.3390\/bios10090110"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"1676","DOI":"10.1039\/D0LC00770F","article-title":"High throughput transepithelial electrical resistance (TEER) measurements on perfused membrane-free epithelia","volume":"21","author":"Nicolas","year":"2021","journal-title":"Lab A Chip"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"142","DOI":"10.2478\/joeb-2018-0019","article-title":"Applications of bioimpedance measurement techniques in tissue engineering","volume":"9","author":"Amini","year":"2018","journal-title":"J. Electr. Bioimpedance"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"5","DOI":"10.1186\/2045-8118-10-5","article-title":"Impedance-based cell monitoring: Barrier properties and beyond","volume":"10","author":"Benson","year":"2013","journal-title":"Fluids Barriers CNS"},{"key":"ref_29","doi-asserted-by":"crossref","unstructured":"Linz, G., Djeljadini, S., Steinbeck, L., K\u00f6se, G., Kiessling, F., and Wessling, M. (2020). Cell barrier characterization in transwell inserts by electrical impedance spectroscopy. Biosens. Bioelectron., 165.","DOI":"10.1016\/j.bios.2020.112345"},{"key":"ref_30","doi-asserted-by":"crossref","unstructured":"Vigh, J.P., Kincses, A., Ozg\u00fcr, B., Walter, F.R., Santa-Maria, A.R., Valkai, S., Vastag, M., Neuhaus, W., Brodin, B., and D\u00e9r, A. (2021). Transendothelial Electrical Resistance Measurement across the Blood\u2013Brain Barrier: A Critical Review of Methods. Micromachines, 12.","DOI":"10.3390\/mi12060685"},{"key":"ref_31","doi-asserted-by":"crossref","unstructured":"Khire, T.S., Nehilla, B.J., Getpreecharsawas, J., Gracheva, M.E., Waugh, R.E., and McGrath, J.L. (2018). Finite element modeling to analyze TEER values across silicon nanomembranes. Biomed. Microdevices, 20.","DOI":"10.1007\/s10544-017-0251-7"},{"key":"ref_32","unstructured":"Profka, A. (2023). Computational Model and Sensitivity Study of Transepithelial\/Transendothelial Electrical Resistance for Optimizing In Vitro Models of Cell Barriers, McGill University."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"375401","DOI":"10.1088\/0022-3727\/49\/37\/375401","article-title":"Geometric correction factor for transepithelial electrical resistance measurements in transwell and microfluidic cell cultures","volume":"49","author":"Yeste","year":"2016","journal-title":"J. Phys. D Appl. Phys."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"1003","DOI":"10.1016\/j.placenta.2008.09.008","article-title":"Long-term Forskolin Stimulation Induces AMPK Activation and Thereby Enhances Tight Junction Formation in Human Placental Trophoblast BeWo Cells","volume":"29","author":"Egawa","year":"2008","journal-title":"Placenta"},{"key":"ref_35","doi-asserted-by":"crossref","unstructured":"Matsukawa, H., Ikezaki, M., Nishioka, K., Iwahashi, N., Fujimoto, M., Nishitsuji, K., Ihara, Y., and Ino, K. (2022). Calnexin Is Involved in Forskolin-Induced Syncytialization in Cytotrophoblast Model BeWo Cells. Biomolecules, 12.","DOI":"10.3390\/biom12081050"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"e14671","DOI":"10.14814\/phy2.14671","article-title":"RNA-Seq identifies genes whose proteins are upregulated during syncytia development in murine C2C12 myoblasts and human BeWo trophoblasts","volume":"9","author":"Azar","year":"2021","journal-title":"Physiol. Rep."},{"key":"ref_37","doi-asserted-by":"crossref","unstructured":"Wang, R., Dang, Y.-L., Zheng, R., Li, Y., Li, W., Lu, X., Wang, L.-J., Zhu, C., Lin, H.-Y., and Wang, H. (2014). Live Cell Imaging of In Vitro Human Trophoblast Syncytialization. Biol. Reprod., 90.","DOI":"10.1095\/biolreprod.113.114892"},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"193","DOI":"10.1093\/humrep\/dei272","article-title":"Differential effects of inducers of syncytialization and apoptosis on BeWo and JEG-3 choriocarcinoma cells","volume":"21","author":"Spitz","year":"2006","journal-title":"Hum. Reprod."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"2041","DOI":"10.1039\/D1LC01046H","article-title":"Real-time monitoring of epithelial barrier function by impedance spectroscopy in a microfluidic platform","volume":"22","author":"Fernandes","year":"2022","journal-title":"Lab A Chip"}],"container-title":["Micromachines"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-666X\/15\/12\/1506\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T16:54:25Z","timestamp":1760115265000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-666X\/15\/12\/1506"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2024,12,18]]},"references-count":39,"journal-issue":{"issue":"12","published-online":{"date-parts":[[2024,12]]}},"alternative-id":["mi15121506"],"URL":"https:\/\/doi.org\/10.3390\/mi15121506","relation":{},"ISSN":["2072-666X"],"issn-type":[{"value":"2072-666X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2024,12,18]]}}}