Nanobubble based sonobiopsy reveals circulating protein signatures of BBB opening and glioblastoma

Focused ultrasound (FUS) and microbubbles can transiently increase blood brain barrier (BBB) permeability, yet verification of BBB opening (BBBO) relies mainly on contrast-enhanced MRI, offering limited insight into the molecular consequences of barrier modulation. Sonobiopsy, which uses FUS induced BBBO to release brain derived molecules into the bloodstream, provides a molecular readout from blood samples. Nanobubbles (NBs) are smaller agents that circulate more effectively in the brain microvasculature and have shown enhanced BBBO in capillaries. Here, NB-mediated proteomic sonobiopsy is used to improve biomarker efflux and increase molecular sensitivity, with the goal of defining the molecular signature produced by BBBO in healthy and glioblastoma (GBM) models, and distinguishing biomarkers associated with tumor pathology from BBBO biomarkers. Plasma collected before and after NB-mediated FUS underwent data-independent acquisition-based mass spectrometry, revealing post-BBBO changes in healthy and tumor bearing mice. In healthy cohorts, 77 proteins were reproducibly altered after BBBO. Six proteins (Dpysl3, Myl1, Mybpc1, Vsig4, Krt33a, Krtap6-5) were detectable only after BBBO in healthy mice. In 005 glioma bearing mice, the BBBO signature identified in healthy animals was preserved, and comparison with matched shams isolated tumor specific effects. Three proteins, Itih4, Lrg1, and Hp, rose significantly after BBBO only in GBM and reached higher post treatment levels than in shams, nominating candidate GBM-associated markers accessible via blood. These findings establish NB-mediated proteomic sonobiopsy as a promising method for BBBO verification and for detecting GBM associated protein signals, supporting the development of scalable BBBO confirmation and protein-based diagnostics in neuro oncology. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=92 SRC="FIGDIR/small/692317v1_ufig1.gif" ALT="Figure 1"> View larger version (27K): org.highwire.dtl.DTLVardef@d0186aorg.highwire.dtl.DTLVardef@1f2fe8borg.highwire.dtl.DTLVardef@25921forg.highwire.dtl.DTLVardef@9c3566_HPS_FORMAT_FIGEXP M_FIG C_FIG