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Mentink, S.

Publications and source records attributed to Mentink, S..

2 recordsLinked to original sources

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↗

Complement active human and porcine serum induces natural competence for genetic transformation in the emerging zoonotic pathogen Streptococcus suis

The acquisition of novel genetic traits by natural competence is a strategy used by bacteria in microbe-rich environments including animal or human hosts where microbial competition, antibiotics and host immune defences threaten their survival. We show here that several virulent strains of Streptococcus suis, an important porcine pathogen and zoonotic agent, become naturally competent for genetic transformation with plasmid or genomic DNA when cultured in active porcine and human serum, but not when it is pre-heated for 30 minutes at 56{degrees}C to inactivate complement. Competence is also not induced in active fetal bovine serum, which contains less complement factors and immunoglobulins than adult serum. Late competence genes, encoding the uptake machinery for environmental DNA, were highly upregulated in active serum. Competence development was independent of the early competence regulatory switch suggesting the presence of an alternative stress-induced pathway for regulation of the transformasome, a type 4-like pilus DNA binding and transport apparatus.

microbiology↗