Deconstructing the role of trans-cellular ion transport in organ formation and function

Project Information

QuantiCl

Grant agreement ID: 101109204

DOI

10.3030/101109204

Project closed

EC signature date 14 April 2023

Start date 1 October 2023

End date 31 March 2026

Funded under

• Marie Skłodowska-Curie Actions (MSCA)

Total cost

No data

EU contribution

€ 189 687,36

Coordinated by

MAX-PLANCK-GESELLSCHAFT ZUR FORDERUNG DER WISSENSCHAFTEN EV
Germany

Periodic Reporting for period 1 - QuantiCl (Deconstructing the role of trans-cellular ion transport in organ formation and function)

Reporting period: 2023-10-01 to 2026-03-31

Summary of the context and overall objectives of the project

Many organs have of a complex structure with lumina and ducts, for example, the pancreas, liver, intestine, etc. Such organs rely on the transport of nutrients and other chemicals from the lumens to the tissue or vice versa for their function and development. These lumens and ducts are lined with epithelial cells, a polarized cell type that faces the lumen on one side (apical side) and the tissue on the other (basolateral side). The transport of nutrients is carried out by transport proteins embedded in both the basolateral membrane and the apical membrane.
The interplay of individual transport proteins in transport processes cells is what ultimately leads to the net transport events, but a solid molecular understanding of these biochemical processes is lacking. Solute transport across epithelia is a molecular process, but leading edge studies until now mainly revolve around bulk measurements, where all transporters are considered but not their unique interplay. This implies that mathematical models based on such measurements have limited predictive value when it comes to the single transport proteins. Changes in single proteins can however easily lead to disruptions in function and to diseases.
QuantiCl aims to bridge this knowledge gap by studying transcellular transport using quantitative biochemistry in epithelial cells and organoids, with specifically Chloride as the target. Chloride is an important anion in the function of many organds, for example, it is exchanged for bicabonate throughout the pancreatic duct, which is then used to neutralize stomach acid, but it is also believed to play a role in lumen formation.
Using a combination of fluorescent chloride sensors in organoids, microscopy and an image and analysis pipeline QuantiCl aims to provide quantitative insights into transcellular chloride transport, within the full complexity of the native cellular environment. These insights will provide key fundamental knowledge on how (membrane) proteins work together and take part in forming complex biological systems.

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

QuantiCl has paved the way to enable quantitative chloride measurements inside epithelial cells and organoids.
To do so, we have introduced a fluorescence based chloride sensor into epithelium-forming cells which can either grow in 2D on a support, or into 3D organoids that form a lumen. The 2D system allows for manipulation of fluids on either side of the epithelium, so cellular conditions can be mimicked.
The 3D system allows us to, next to chloride measurements, also look at organoid development in parallel.
We developed a microscopy pipeline and image analysis pipeline that can be used to study the effect of inhibitors on chloride transport and lumen formation. Using this pipeline, we can deconvolute the role of individual transport proteins in transepithelial chloride transport, under various physiological conditions.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

Up until this point the experimental system and analysis pipelines are in place, but took more time than anticipated due to biological challenges. Further research is currently going on to ensure further the success of quantitative chloride measurements over epithelial cells.