Retina Organoid Mechanobiology

Project Information

ROMB

Grant agreement ID: 850691

DOI

10.3030/850691

EC signature date 24 February 2020

Start date 1 September 2020

End date 31 December 2026

Funded under

• EXCELLENT SCIENCE - European Research Council (ERC)

Total cost

€ 1 497 175,00

EU contribution

€ 1 497 175,00

Coordinated by

UNIVERSITAET ULM
Germany

Periodic Reporting for period 3 - ROMB (Retina Organoid Mechanobiology)

Reporting period: 2023-09-01 to 2024-12-31

Summary of the context and overall objectives of the project

The ROMB (Retina Organoid Mechanobiology) project aims to develop a biophysical model for the human retina in order to study neurodegenerative diseases, such as Alzheimer's disease, outside the human body. The project utilizes three-dimensional cell ensembles called retina organoids, which are grown from stem cells capable of differentiating into various cell types found in the retina.
The objectives of the ROMB project can be summarized as follows:
1. Establishing a comprehensive and reliable biophysical model for the retina: The primary objective is to overcome the limitations of current retina organoid research, such as uncontrolled variations in cell and tissue organization. By understanding the mechanical signals that guide organoid growth and quantifying the mechanical properties of the retina, the project aims to engineer a more reproducible cellular mechanical niche within the organoids. This will help in better understanding how mechanical forces influence cellular behavior and guide the development and function of the retina. Ferrofluid droplets are used as mechanical actuators to measure retina mechanics.
2. Studying Alzheimer's disease in vitro: The ROMB project evaluates the feasibility of using retina organoids to study neurodegenerative diseases like Alzheimer's disease. By growing retina organoids with cells carrying specific mutations associated with Alzheimer's disease, the project aims to gain insights into the mechanisms, including the mechanical aspects, of the disease. This approach can potentially be used to test therapeutic interventions.
3. Recording 3D neuronal function using lightsheet microscopy: The third objective of the ROMB project is to record the 3D neuronal function within retina organoids, which is still an unsolved problem in the field. To achieve this, a custom-developed lightsheet microscopy technique is employed. This microscopy technique enables the quantification of electrical functionality within the organoids and allows for the relationship between neuronal function and the mechanical properties of the retina to be explored.
By achieving these objectives, the ROMB project aims to contribute to an improved understanding of the biophysical properties of the retina, as well as the development of new diagnostic techniques, treatment strategies, and potential preventive measures for neurodegenerative diseases affecting the central nervous system, such as Alzheimer's disease.

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

Achievements which have been made in the ROMB project including the following:
Retina organoids were successfully generated from both mouse embryonic stem cells and human induced pluripotent stem cells. These organoids provide a miniature representation of the human retina and serve as valuable models for studying its structure and function.
To identify and characterize the major cell types present in human retinal organoids, immunofluorescence techniques were employed. This allowed the team to image the diverse cell populations that make up the organoids.
To study the mechanical properties of the retinal organoids, ferrofluid droplets were utilized as mechanical actuators. These actuators were carefully constructed, tested, and calibrated to ensure accurate measurements of mechanical properties, including the elastic modulus and viscosity, within living organoids.
In order to streamline data analysis, a Python software tool was developed. This software simplifies the process of analyzing the mechanics data collected from the retinal organoids, making it easier to extract meaningful insights from our experiments.
The successful establishment of magnetic droplet technology and their optimization for its use in human retinal organoids has been a success of the project. This advancement enables us in the near future to characterize the mechanical properties of the retinal organoids, contributing to a better understanding of the organoids' mechanics aspects and their development.

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)

One milestone in the ROMB project involved the development of a minimalistic microscope, which allows the recording of organoid neuronal responses in 3D (Wysmolek et al., Scientific Reports, 2022). Due to its simplicity and fast recording speeds it provides a significant benefit for the research community. In a proof of principle experiment we recorded and quantified neuronal responses in stem-cell derived 3D tissues. During the design phase, the team gained valuable insights into important aspects and determined improvements for future devices. As a result, a new prototype of the lightsheet microscope was created, which can combine fast volumetric imaging with mechanical actuation. As mechanics and function of neurons is tightly intertwined, this advanced version has the potential to make a substantial impact in the field. We expect a publication within the remaining half of the ERC grant period.

Image of 100-day old Alzheimer retina organoids grown from human induced pluripotent stem cells.