Ph.D. defence of Miriam Dutková

On Friday, April 27, our colleague Mirim Dutková defended her dissertation. 

This thesis investigates vesicle-mediated communication between the gut microbiota and host innate immune cells. It focuses on membrane vesicles (MVs) derived from the Gram-positive bacteria Lacticaseibacillus rhamnosus and Enterococcus faecium, and on extracellular vesicles (EVs) released by macrophages in response to bacterial stimulation. The work demonstrates that bacterial MVs activate macrophages in a TLR2-dependent manner and provide inflammasome-priming signals, with their immunostimulatory capacity influenced by bacterial growth phase. Stimulated macrophages subsequently release molecularly remodeled EVs with distinct protein and lipid profiles, which propagate microbial signals to naïve macrophages and endothelial cells and are detectable in vivo during inflammatory conditions. Altogether, the thesis defines a bidirectional vesicle-mediated communication axis linking Gram-positive bacteria and host cells, advancing our understanding of how EVs contribute to intestinal immune homeostasis and inflammation.