Monitoring the endothelial cell behavior during flow stress induction using digital holographic microscopy

abstract

English

The arterial endothelium is exposed to physical stress associated with blood flow and plays an essential role in maintaining vascular homeostasis in response to hemodynamic forces. Endothelial cells are in direct contact with flowing blood and their response to physiological and pathological flow dynamics affects the health of blood vessels [1]. The inclusion of computational modeling in cell mechanics research is a very promising tool for understanding the events taking place at the cellular level. A huge advantage of computational simulations is the possibility of connecting the cause and effect of behavior even for such values, which are either not possible or demanding to measure in vivo. The current hybrid computational model of a single endothelial cell considers all mechanically significant organelles [2], but suffers from a lack of information about the behavior of individual organelles. Such model can be optimized by comparing the model response with the real behavior of the cell under defined conditions. This study aims to monitor the elastic behavior of individual endothelial cells during fluid flow. A measuring set according to Fig. 1 is created for the implementation of experiments. The application of flow stimuli is provided by the microfluidic system Fluigent Flow EZ (FLUIGENT INC., Germany). First, a set of rectangular pressure pulses in Fluigent OxyGEN software is proposed. Then, pressure changes are converted to flow pulses by Fluigent Flow EZ controller. Finally, these flow pulses are applied to individual endothelial cells (Human umbilical vein endothelial cells) cultured in a channel slide (µ-Slide VI 0.1, ibidi). The video sequences of the cells are acquired with a T1000 digital holographic microscope (Lyncée Tec, Switzerland), which provides a label-free and minimally invasive technology for quantitative cell imaging. The microscopic images of selected cell before and during the experiment are shown in Fig. 2 and Fig. 3. They show that the cell mass is shifted in the direction of the fluid flow during application of a pressure pulse. The obtained real flow data together with analyzed cell responses on the flow stimuli are used to further analyze the shear stress applied to the endothelial cells and this can be used to later update of existing endothelial cell model.

Endothelial cells, Microfluidic system, Digital holographic microscopy

ZUMBERG, I.; ČMIEL, V.; ORLOVÁ, L.; HASHEMI, A.; JAGOŠ, J.

4. 9. 2022

Czechoslovak Microscopy Society

Brno

978-80-11-02253-2

16th Multinational Congress on Microscopy 16MCM: BOOK OF ABSTRACTS

304

305

2

https://www.16mcm.cz/wp-content/uploads/2022/09/16MCM-abstract-book.pdf