Lucile Alexandre | Searcharxiv

arXiv2025

Illuminating extracellular vesicles biology with super resolution microscopy: Insights into morphology and composition

Super-Resolution Microscopy (SRM) is emerging as a powerful and innovative tool for imaging, characterizing, and understanding the structure of Extracellular Vesicles (EVs). By addressing the need for single-particle analysis with the high resolution required to study the composition and organization of these nanoparticles, SRM provides unique insights into EV biology. However, its application is accompanied by significant challenges, ranging from experimental setup to data analysis. This review outlines the fundamentals of SRM and its position within the broader field of EV research. We then explore its applications in evaluating (i) the morphological structure of EVs, (ii) their molecular composition, and (iii) their roles in biological systems. By offering practical guidance and an overview of critical parameters for standardization, this review aims at providing researchers with the tools and insights necessary to effectively apply SRM to EV investigation.

physics.bio-ph↗

arXiv2023

Co-Enrichment of Proteins in Extracellular Vesicles

Extracellular vesicles (EVs) are cell-derived secretions that mediate tissue homeostasis and intercellular communication through their diverse cargos, such as proteins. Distinct EV biogenesis pathways suggest specific association and co-enrichment of proteins sharing a biogenesis pathway, and non-association and co-depletion of proteins segregated into distinct pathways. Yet these associations elude conventional protein expression or co-expression measurements. Here, we propose and define pairwise protein co-enrichment (CoEn) to quantify whether a given protein is co-enriched or co-depleted with another protein relative to its overall expression. We measure CoEn, and differential CoEn (dCoEn) between a stimulus and a reference condition, of up to 240 protein pairs in EVs using antibody microarrays. We validate CoEn by modulating well-known EV biogenesis pathways, and find that dCoEn quantifies expected changes between perturbed and reference conditions while uncovering new ones; CoEn and dCoEn in three model cell lines and parental and organotropic breast cancer progeny cell lines reveals both preserved and variable CoEn that may warrant further studies. Collectively, our result suggest that CoEn reflects and illuminates cell physiology and EV biogenies, is readily measurable, and could further serve as quality control in EV biomanufacturing as well as underpin new EV biomarkers.

q-bio.QM↗