Revealing cellular behavior with single-cell multi-omics

Project Information

X CELL

Grant agreement ID: 101041224

DOI

10.3030/101041224

EC signature date 20 April 2022

Start date 1 September 2022

End date 31 August 2027

Funded under

• European Research Council (ERC)

Total cost

€ 2 499 864,00

EU contribution

€ 2 499 864,00

Coordinated by

UPPSALA UNIVERSITET
Sweden

Periodic Reporting for period 1 - X CELL (Revealing cellular behavior with single-cell multi-omics)

Reporting period: 2022-09-01 to 2025-02-28

Summary of the context and overall objectives of the project

The prevalence of type 2 diabetes is increasing around the globe and is often linked to food choices and exercise. A key to type 2 diabetes is the dysfunction of beta cells. Beta cells reside in the pancreatic islets and are the only cells in the body that can release insulin. In type 2 diabetes, beta cells are no longer releasing insulin into the blood stream when the blood glucose levels increase. This results in high blood glucose levels, which leads to complications and damage to organs. To find preventive measures and treatments to type 2 diabetes it is essential to understand why the beta cell stops releasing insulin.

In this project, the aim is to decipher the chemical processes inside the beta cell that are responsible for the failure to release insulin in type 2 diabetes. This needs to be done in individual cells since every cell and their chemical behavior is unique. Thus, cells may have many differences within the 2 min from sensing glucose to releasing insulin. This aim is ambitious for several reasons: 1) the size of an individual cell is only 20 µm in diameter (corresponding to 0.02 mm) making them hard to handle and see; 2) the small size also means that the amount of chemistry to detect is limited and; 3) the process is dynamic and is believed to include various known and unknown metabolic pathways. Therefore, the first part of the project involves building technologies to enable detection of molecules in an individual cell using mass spectrometry. In the second part of the project, the developed techniques will be used to investigate the chemistry of individual insulin releasing cells. By ultimately using donated human beta cells the project aims to find the bottleneck in the chemical processes that are essential for insulin release. Pinpointing the bottleneck will lead to opportunities to identify ways to help those at risk or affected by type 2 diabetes.

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

Despite the minute size of a single cell, the project has successfully developed techniques to monitor its chemistry. A motorized and computer-controlled platform has been constructed. This allows for moving the cells on the special cell holder for subsequent sampling and analysis. It is important to have a relatively automated system because the difference between cells can only be detected by analyzing many individual cells. With the developed platform around one hundred individual cells can be analyzed in one round.

Up till now, the project has used a commercially available immortalized cell line that is derived from rats. These cells can release insulin upon glucose exposure. Together with the developed platform this allows us to peek into the chemical machinery of a single cell. In study of two hundred individual cells a distribution of the cellular chemistry was detected. Furthermore, cells that were exposed to glucose showed a significant shift in the abundances of several small molecules, including valine and glutamate. This suggests that these molecules are important in insulin release, which is an exciting result since they belong to previously unmapped metabolic pathways involved in insulin release.

The project results so far demonstrate the feasibility of deciphering the chemical processes linked to insulin secretion. To link this to type 2 diabetes it is important to conduct additional studies using human beta cells. Overall, the project has made great progress in the technique developments and gained unique preliminary results detailing the chemical processes involved in insulin secretion from individual cells.

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)

The ability to detect the chemistry in individual cells to the level achieved within the project is beyond the forefront of the field and will have implications outside of type 2 diabetes. The developed techniques could be used in various other disease states, including cancer and neurodegeneration, to learn the inside mechanisms of the disease. In type 2 diabetes the identification of the chemical processes in insulin secreting cells can greatly impact our understanding of type 2 diabetes. Learning about the chemical factors behind dysfunctional insulin release in human cells will provide an essential part of the puzzle to understand type 2 diabetes onset, progression and healing.