Human endothelium-on-a-chip : development of a microfluidic model for cell viability assessment under oxidative injury

Kirbus, Klemen (author), Kolar, Jakob (author), Krebs, Črt (author), Kocbek, Petra (author), Žiberna, Lovro (author)

Endothelial responses to oxidative stress are influenced by the presence of blood flow and shear stress. To better capture these conditions in vitro, we developed an endothelium-on-a-chip model for the study of acute oxidative injury in EA.hy926 cells under flow. We adapted the culture conditions for use outside a conventional 5% CO$_2$ atmosphere, and we improved endothelial adhesion and retention under flow by collagen coating of the chip surface. Our model tolerated shear stress of up to 0.89 Pa, which corresponds to the in vivo values experienced by endothelial cells in the aorta and venous system. On this model, we designed an acute oxidative injury protocol based on high concentrations of hydrogen peroxide ($H_{2O_2}$) as an endogenous source of oxidative stress and 2,2′-azobis(2-amidinopropane) dihydrochloride (AAPH) as an exogenous molecule. The inclusion of flow increased the apparent sensitivity of the model to oxidative injury compared to static conditions, as the IC$_{50}$ values decreased from 16.2 mM to 12.0 mM for ($H_{2O_2}$) and from 100.7 mM to 72.5 mM for AAPH under flow conditions. Pretreatment with quercetin (1.5 µM) reduced AAPH-induced oxidative injury, thus showing the potential applicability of the model for antioxidant screening assays.

• Language: English
• Keywords: endothelium, organ-on-a-chip, microfluidics, oxidative stress, shear stress, cell viability
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FFA - Faculty of Pharmacy; MF - Faculty of Medicine
• Publication status: Published
• Publication version: Version of Record
• Year: 2026
• Number of pages: 20 str.
• Numbering: Vol. 27, iss. 11, art. 5018
• PID: 20.500.12556/RUL-183079
• UDC: 612.015+611.018.74
• ISSN on article: 1422-0067
• DOI: 10.3390/ijms27115018
• COBISS.SI-ID: 280213251
• Publication date in RUL: 04.06.2026

Record is a part of a journal

• Title: International journal of molecular sciences
• Shortened title: Int. j. mol. sci.
• Publisher: MDPI
• ISSN: 1422-0067
• COBISS.SI-ID: 2779162

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.

Secondary language

• Language: Slovenian
• Keywords: organ na čipu, mikrofluidika, strižna napetost, celična viabilnost, oksidativni stres, endotelij