Recapitulating and preventing epileptogenesis in early human brain network development

Project Information

Epi-Stop

Grant agreement ID: 101155338

DOI

10.3030/101155338

Project closed

EC signature date 6 March 2024

Start date 1 April 2024

End date 31 March 2026

Funded under

• Marie Skłodowska-Curie Actions (MSCA)

Total cost

No data

EU contribution

€ 183 600,96

Coordinated by

INSTITUT FUER MOLEKULARE BIOTECHNOLOGIE GMBH
Austria

Periodic Reporting for period 1 - Epi-Stop (Recapitulating and preventing epileptogenesis in early human brain network development)

Reporting period: 2024-04-01 to 2026-03-31

Summary of the context and overall objectives of the project

Epilepsy affects tens of millions of people worldwide, and around one in three patients does not respond to existing anti-seizure medicines. A major reason is that current drugs treat the symptoms, the seizures, rather than preventing the underlying disease process by which a healthy brain network becomes epileptic. That process, called epileptogenesis, often begins very early in development, before any seizure occurs, which makes it extremely difficult to study in people. Tuberous Sclerosis Complex (TSC) is a genetic condition and a leading cause of childhood drug-resistant epilepsy. Because TSC has a known genetic cause and the epilepsy frequently begins in infancy, it offers a valuable window onto how epilepsy first develops in the human brain. Until now, however, there has been no good way to observe this earliest, prenatal stage of human epileptogenesis in the laboratory.

The Epi-Stop project set out to close that gap using human cerebral organoids - three-dimensional models of early brain tissue grown from human stem cells. The overall aim was to build a TSC organoid model that reproduces the early electrical changes seen in patients, to understand the biological mechanism that drives those changes, and to test whether the disease process can be stopped before it takes hold. The project pursued three objectives: to identify the electrical signatures of developing epilepsy in the model, to uncover the cellular and molecular changes responsible, and to test whether specific drugs applied at a critical developmental window can prevent the pathology from emerging.

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

Working with patient-derived stem cell lines and matched healthy control lines, the project grew TSC and control organoids and recorded their electrical activity repeatedly over several months of development. A custom open-source software pipeline was built to detect and characterise high-frequency oscillations - a specific electrical pattern that clinicians use to locate epilepsy-causing tissue in patients. The same analysis was applied both to the organoid recordings and to clinical recordings from patients, allowing a direct comparison between model and human disease.

To identify the cells responsible, the project labelled and recorded from a particular class of inhibitory nerve cell that arises during a defined stage of development, combining electrical recordings, single-cell measurements of cell properties, and detailed imaging of cell structure. Finally, the project tested several clinically relevant compounds, applied over the long term during the critical developmental window, to see whether they could prevent the disease signature from appearing.

The project successfully built a human organoid model that reproduces, in the laboratory, the same electrical biomarker used clinically to identify epilepsy-causing tissue in TSC patients. The electrical signatures that emerge in the TSC organoids closely match key features of those recorded from patients, establishing the model as a faithful and tractable system for studying the earliest stages of human epileptogenesis.

The project identified a specific developmental subtype of inhibitory nerve cell as a driver of the abnormal network synchronisation that underlies the epileptic signature. It further showed that this cell population is over-produced in TSC organoids and that reducing it lessens the abnormal activity.
Most importantly, the project demonstrated that long-term inhibition of a particular cell-signalling pathway, applied during the critical developmental window, prevents the epileptic phenotype from emerging - both in terms of electrical activity and of the underlying changes in cell structure and number. To the project's knowledge, this is the first demonstration of pharmacological prevention of epileptogenesis in a human laboratory model.

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)

Epi-Stop moves the study of genetic epilepsy beyond seizure suppression toward genuine prevention. By recreating early human epileptogenesis in a dish and showing it can be interrupted, the project offers a mechanism-based route to intervening before epilepsy becomes established - a fundamentally different therapeutic strategy from today's symptom-focused medicines.

The potential impact is significant given the scale of unmet need in drug-resistant epilepsy, which affects around one in three epilepsy patients. Because the cell-signalling pathway identified can be targeted with drugs that are already approved for other medical uses, the findings point toward a repurposing-friendly path to a future clinical-trial concept for preventive treatment in children with TSC who are at risk but not yet symptomatic.

Realising this potential will require further work: confirmation of the findings in complementary models, refinement of the timing and safety of preventive treatment, and engagement with clinical partners and patient organisations to design a trial concept. To support uptake by the wider research and clinical community, the project's validated organoid model, open-source analysis software, shared experimental protocols and cell lines, and open-access publication are all designed to lower the barrier for others to build on the work. The underlying approach also contributes to European priorities in health and in open, digital, FAIR-compliant research.