Malaghan visiting researcher: Dr Johanne Jacobsen

The study of germinal centers is a specialised field within immunology, focusing on dynamic microstructures that form in response to infection or vaccination. These structures are fundamentally important because it is within them that B-cells rapidly mutate and compete to be selected for their ability to recognise and neutralise threats. 

Dr Jacobsen, from the University of Oslo’s Institute of Immunology, visited the Malaghan Institute and connected with fellow germinal centre researcher Dr Michelle Linterman, whose team investigates how aging affects the immune system’s ability to develop these targeted responses.

“Germinal centres are pressure cookers of evolution” says Dr Jacobson.

“Within them, B cells rapidly mutate and compete to be selected for their ability to recognise and neutralise threats.”

Dr Jacobsen’s work focuses on uncovering the molecular mechanisms that govern this process, particularly the T-cell subsets that regulate germinal centre activity. 

A highlight of her seminar were colourful videos showing different immune cell types moving and interacting in real time within a germinal centre, a striking visualisation of an otherwise invisible process.

Using advanced tools to cut through biological noise, Dr Jacobsen’s lab is helping to precisely map the pathways that shape our immune response, with the aim of fine-tuning immunity through better vaccines and therapies.