Biology subjects

Barry-Carroll, L.

Publications and source records attributed to Barry-Carroll, L..

5 recordsLinked to original sources

bioRxiv2026

Cutting-edge microfluidic technology allows detection and sorting of single fluorescent extracellular vesicles

Extracellular vesicles (EV) are cell-secreted, nanosized biological particles that are involved in most physiological and pathophysiological processes. Their composition and properties reflect the pathophysiological state of the producing cell, tissue, and organ. Released into biological fluids, they may be used as a potential source of non-invasive biomarkers for diagnosis, prognosis or therapeutic follow-up in several diseases such as cancer. However, despite the development of single-EV analysis technologies, the sorting of EV subpopulations for downstream analysis remains a major challenge. Here, we describe a novel instrument that combines a highly sensitive optical detection system with an advanced lab-on-a-chip device. Using engineered fluorescent small extracellular vesicles (sEV), we demonstrate that the Hekat NanoSorter enables sensitive, scalable, and reproducible detection and sorting of individual sEVs for downstream analysis by cryo-EM. Furthermore, detailed characterization of the sorted EV populations, together with the detection of sEVs labeled with an in vitro pathophysiological marker, demonstrates the ability of the NanoSorter to monitor and enrich clinically relevant EV-associated biomarkers. These findings highlight the clinical potential of extracellular vesicle sorting for their use as biomarkers for therapeutic monitoring and treatment outcome assessment.

bioengineering↗

bioRxiv2026

The autophagy core protein Atg18 regulates exosome release and rescues pathogenic dysfunction associated to Parkinson Sac domain mutation in Synaptojanin

Macroautophagy, a catabolic process conserved across evolution, participates in fundamental aspects of synaptic function and neuronal survival. Exosomes are extracellular vesicles that mediate cell communication, including emerging roles mediating brain intercellular signaling, synaptic function and neuronal survival. Indeed, both autophagy and exosome release interact with each other, but this interplay is poorly characterized at the neuronal synapse, especially in the context of neurodegenerative diseases. Here, we report that at the presynaptic compartment the autophagy protein Atg18a/WIPI2 regulates exosome release at the level of the multivesicular body. The Parkinson disease mutation R258Q in the protein Synaptojanin inhibits synaptic autophagy, and causes locomotion deficits, seizures and neurodegeneration. We found that this mutation also reduces exosome release and that the dopaminergic overexpression of Atg18a in Synaptojanin mutant animals restores exosome release, locomotion and dopaminergic survival without restoring synaptic autophagy. Our data reports a novel function of Atg18a in the regulation of exosome release and spotlights the role of exosome release in the pathogenesis of Parkinson disease.

neuroscience↗

bioRxiv2026

Standardized brain and plasma EV enrichment pipeline validated for Single sample multi-Omic and fatty acids applications in Mouse and Human

Extracellular vesicles (EVs) are key mediators of intercellular communication, yet their molecular profiles across tissues and species remain poorly characterized, particularly due to currently available methods requiring a large amount of biological material (tissue or biofluids). Here, we established a workflow allowing the deep phenotyping of EV cargos starting from single samples of human and mouse origin. We took advantage of standardised EV isolation procedures and multi-omic techniques for the isolation and analysis of EVs from brain and plasma of human and mouse, integrating flow cytometric profiling, proteomics, miRNA sequencing, and fatty acid profiling. Here we report specific brain-derived EVs proteome, enriched in neuronal and glial proteins, polyunsaturated fatty acids profiles, and distinct miRNAs. At the periphery, we also report plasma-derived EVs signatures reflecting immune, metabolic, and systemic transport functions. Despite these expected material-specific differences, EVs from the same source displayed greater similarity across species than EVs from different material, supporting the translational relevance of mouse models. Importantly, using state-of-the-art miRNA profiling approach, we identified novel EV-specific miRNAs in human and mouse brain EVs, potentially allowing the exploration of new roles in neuronal signalling. Overall, we report here a method enabling deep multi-omic characterization from minimal starting material, offering a practical approach for studies with limited biological samples. These findings also demonstrate that the origin strongly shapes EV composition, highlighting conserved and species-specific molecular features, and provide a scalable framework for multi-omic investigations of EV biology. Summary StatementWe present a standardised workflow allowing multi-omic profiling of brain and plasma-derived EVs from minimal human and mouse material. Our findings reveal both tissue-specific and species specific EV molecular signatures.

neuroscience↗

bioRxiv2022

Microglial colonisation of the developing brain is facilitated by clonal expansion of highly proliferative progenitors and follows an allometric scaling

Microglia are the resident immune cells of the brain and arise from yolk sac-derived macrophages during early embryogenesis. On entering the brain, microglia undergo in situ proliferation and eventually colonise the entire brain by the second and third postnatal weeks in mice. However, the intricate dynamics of their developmental expansion remain unclear. Here, we examine and characterise the proliferative dynamics of microglia during embryonic and postnatal development. Using complementary fate-mapping techniques, we demonstrate that the developmental colonisation of the brain by microglia is facilitated by clonal expansion of highly proliferative microglial progenitors that occupy spatial niches throughout the brain. We also find that the distribution of microglia switches from a clustered to a random pattern between embryonic and late postnatal development. Moreover, the developmental increase in microglia follows the proportional growth of the brain in an allometric manner with the density of microglia eventually stabilising when the mosaic distribution has been established. Overall, our findings offer insight into how the competition for space acts as a driving force for microglial colonisation by clonal expansion during development.

neuroscience↗

bioRxiv2021

Spatiotemporal dynamics of human microglia are linked with brain developmental processes across the lifespan

Microglia, the brains resident macrophages, shape neural development and wiring, and are key neuroimmune hubs in the pathological signature of neurodevelopmental disorders. In the human brain, microglial development has not been carefully examined yet, and most of our knowledge derives from rodents. We established an unprecedented collection of 97 postmortem tissues enabling quantitative, sex-matched, detailed analysis of microglial across the human lifespan. We identify the dynamics of these cells in the human telencephalon, describing novel waves in microglial density across gestation and infancy, controlled by a balance of proliferation and apoptosis, which track key neurodevelopmental milestones. These profound changes in microglia are also observed in bulk RNAseq and single-cell RNAseq datasets. This study provides unparalleled insight and detail into the spatiotemporal dynamics of microglia across the human lifespan. Our findings serve as a solid foundation for elucidating how microglia contribute to shaping neurodevelopment in humans.

neuroscience↗