Mentink, A. | Search bioRxiv

bioRxiv2024

The Mag-Click-Capture-Release Technology for Selective Capture and Release of Hepatocyte-Derived Extracellular Vesicles as Biomarkers for Liver Disease

Chronic liver diseases, such as liver cirrhosis and hepatocellular carcinoma (HCC), present major global health challenges, often diagnosed late. Circulating extracellular vesicles (EVs), which carry disease-specific biomolecular cargo, is emerging as an early diagnostic and prognostic biomarker for several diseases including cancer. However, current EV purification methods including ultracentrifugation and size exclusion chromatography present several limitations. Here, we present the Mag-Click-Capture-Release Technology for selective capture and release of EVs that combines magnetic beads, trans-cyclooctene (TCO) and tetrazine (Tz) click chemistry, immuno(antibody)-based capture and disulfide-driven release of EVs. Importantly, the Mag-Click-Capture-Release Technology is customizable, whereby using specific antibodies conjugated to TCO antibodies, different EV subtypes can be selectively captured and released for further analysis. With our Mag-Click-Capture-Release Technology, we successfully isolated hepatocyte-derived EVs from human serum with good recovery, high specificity and purity when compared with standard ultracentrifugation. Validation in serum samples obtained from cirrhosis and HCC patients with alcohol-associated liver disease evidenced an increasing trend in hepatocyte-EV levels correlating with disease severity, suggesting potential for early diagnosis and prognosis. In conclusion, we present here the Mag-Click-Capture-Release Technology, a customizable and efficient approach for selective isolation of organ-, cell-specific, and disease-relevant EVs from biological samples that can be subsequently released for downstream molecular EV analysis and EV-related functional assays.

bioengineering↗

bioRxiv2017

The effect of smoking on the brain revealed by using electronic cigarettes with concurrent fMRI

Cigarette addiction is driven partly by the physiological effects of nicotine, but also by the distinctive sensory and behavioural aspects of smoking, and understanding the neural effects of such processes is vital. There are many practical difficulties associated with subjects smoking in the modern neuroscientific laboratory environment, however electronic cigarettes obviate many of these issues, and provide a close simulation of smoking tobacco cigarettes. We have examined the neural effects of smoking electronic cigarettes with concurrent functional Magnetic Resonance Imaging (fMRI). The results demonstrate the feasibility of using these devices in the MRI environment, and show brain activation in a network of cortical (motor cortex, insula, cingulate, amygdala) and sub-cortical (putamen, thalamus, globus pallidus, cerebellum) regions. Concomitant relative deactivations were seen in the ventral striatum and orbitofrontal cortex. These results reveal the brain processes involved in (simulated) smoking for the first time, and validate a novel approach to the study of smoking, and addiction more generally.

neuroscience↗