WEHI Immunity special seminar hosted by Dr Niall Geoghegan

Dawson Ling BSc BBiomed (Hons) PhD

Research Officer

Rogers Lab, Centre for Dynamic Imaging – Technological Sciences Division

Immunity Division, WEHI

Expansion Microscopy: Bigger Samples, Sharper Views

L7W Seminar Room

Join via TEAMS

Including Q&A session

Fluorescence microscopy has transformed our ability to study biological systems, but many cellular structures and molecular interactions remain unresolved due to the diffraction limit of light. Expansion microscopy (ExM) provides an alternative strategy by physically enlarging biological specimens, enabling nanoscale visualisation using conventional fluorescence microscopes.

In this seminar, I will introduce the evolution of expansion microscopy technologies, from the original ExM approachthrough newer variants including X10, ultrastructure expansion microscopy (U-ExM), and Magnify. I will discuss howmodifications in fixation, anchoring chemistry, homogenisation and expansion strategies have been developed to addressdifferent biological questions, balancing resolution, biomolecule retention, isotropy and compatibility with downstreamapplications. Beyond imaging, I will highlight emerging applications of expansion microscopy across biological disciplines, including nanoscale tissue imaging for histopathology, visualisation of molecular architecture within cells, and integration with spatial proteomics approaches. These examples demonstrate how expansion microscopy is developing into a broader platform technology that complements existing imaging and molecular profiling approaches. Finally, I will discuss our application of U-ExM to blood-stage Plasmodium falciparum malaria. The invasion of red blood cells requires precise coordination of specialised parasite organelles, cytoskeletal structures and host–parasite interactions that occur at the nanometre scale. I will describe how expansion microscopy provides new opportunities to resolve parasite ultrastructure and investigate the organisation of invasion machinery beyond the capabilities of conventional microscopy. This seminar will highlight how choosing the appropriate expansion microscopy strategy can enable new biological insights, from tissue pathology to molecular mechanisms of infectious disease.

Dawson Ling is a postdoctoral researcher in the Centre for Dynamic Imaging at WEHI. His research focuses on understanding how Plasmodium falciparum invades human red blood cells using advanced microscopy approaches, including lattice light sheet microscopy and expansion microscopy. He completed his PhD at the Burnet Institute, where he investigated the mechanism of action of invasion-blocking antimalarial compounds and identified parasite proteins involved in invasion-related lipid metabolism and signalling.

All Welcome!