Zoek in de site...

Online seminar by dr. Daan Vorselen: 'Deformable microparticles reveal complex cellular forces during phagocytosis' (Lecture)

Monday 23 November 2020Add to my calendar
11:00 to
dr. Daan Vorselen (Dept. of Biology, University of Washington, Seattle, USA)

Daan VorselenPhagocytosis, the uptake of solid particles by cells, allows our immune cells to respond to widely differing threats, from invading microbes during infection to damaged and malignant cells in tissue homeostasis. These phagocytic targets differ greatly in their physical properties, such as size, shape and rigidity. How macrophages are able to adapt phagocytic mechanisms to robustly internalize targets with such diverse physical properties is unknown. To address this question, we recently developed a particle-based force microscopy method that allows precise probing of the interaction between immune cells and their targets. We synthesize uniform, deformable and highly tuneable hydrogel microparticles, which can further be chemically modified to trigger a phagocytic response by macrophages. The 3D shape of such particles can be resolved with superresolution (<50 nm) accuracy using conventional confocal microscopy. A new computational framework then allows inference of both shear and normal traction forces (>10 Pa) exerted by the cell, directly from the deformed particle shape. This approach reveals unexpected and spatially complex force exertion by macrophages, and indicates how contractile mechanism and dynamic actin-based adhesion structures ("teeth") may help phagocytes to resolve complex target encounters that can arise in vivo. Together, these results provide an unprecedented quantitative look at immune-cell target interactions and challenge the current models for phagocytic upta

prof. Ger Pruijn