The German National Academy of Sciences Leopoldina honors the Finnish biochemist Prof. Dr. Kai Simons with the Cothenius Medal for his outstanding scientific life’s work. The award ceremony will take place on 25 September 2025 as part of the Leopoldina Annual Assembly in Halle (Saale).

Kai Simons, born in 1938, has had a lasting impact on cell biology and biochemistry through his groundbreaking work on the structure and function of cell membranes. His research began in Helsinki with studies on the Semliki Forest virus (SFV), which he used as a model to study the interaction of viruses with host cells. Simons clarified how detergents make cell membranes soluble, which enabled the development of protein subunit vaccines. His team provided the first evidence of how SFV enters host cells, a mechanism that remains relevant for understanding enveloped viruses such as coronaviruses.

At the European Molecular Biology Laboratory (EMBL) in Heidelberg (1975–2000), Simons focused his work on the polarity of the cell surface and lipid sorting in epithelial cells. This led to the discovery of lipid rafts, dynamic microdomains in cell membranes that play a key role in signal transduction and disease processes. From 1998, Simons was founding director of the Max Planck Institute of Molecular Cell Biology and Genetics in Dresden, where he worked until his retirement in 2006. He also pioneered lipidomics by using mass spectrometry to analyze lipid diversity and function. His work identified lipid biomarkers for metabolic disorders, cardiovascular disease and diabetes that promote early detection and personalized therapies.

Simons is a member of numerous renowned academies, including the Leopoldina (since 1999), EMBO and the National Academy of Sciences (USA). He has already been awarded the Schleiden Medal (2001) and the Robert Koch Medal in Gold (2016). The Cothenius Medal, which goes back to a foundation by Leopoldina member Christian Andreas von Cothenius, has been awarded since 1792 and has honoured the scientific life’s work of outstanding researchers since 1954. Previous award winners include Ernst Haeckel and Konrad Zuse.

The award highlights Simons’ significant contributions to cell biology, which have not only created a fundamental understanding of cell membranes and viral infections, but have also opened up new avenues for medical applications.

Editor: X-Press Journalistenbüro GbR

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