Small volumes, deep insights: longitudinal plasma EV multi-omics in very preterm infants

Abstract Very preterm birth disrupts critical fetal developmental programs, yet the systemic molecular trajectories driving extrauterine adaptation remain poorly defined. Although extracellular vesicles (EVs) represent informative systemic compartments, comprehensive multi-omics is constrained by the small plasma volumes safely obtainable from neonates. Here, we adapted a magnetic bead-based framework (Mag-Net) to enable parallel EV proteomics and lipidomics from the same EV-enriched preparation using 10 µL of plasma. Across 74 longitudinal samples collected from birth to term-equivalent age, we quantified 1,528 EV-associated proteins and 421 lipid species. The EV proteome shifted from early translation and metabolic programs toward progressive immune competence, while the lipidome underwent selective structural remodeling enriched in triacylglycerols and ether-linked phosphatidylcholines. Cross-omics integration identified coordinated protein-lipid modules associated with clinical phenotypes, including brain injury. This study demonstrates that parallel EV proteomic-lipidomic profiling from microliter plasma volumes is feasible and captures coordinated developmental and clinically relevant programs in very preterm infants.