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Wiklander, O.

Publications and source records attributed to Wiklander, O..

3 recordsLinked to original sources

Evaluation of Tetraspanins in Extracellular Vesicle Bioengineering

Extracellular vesicles (EVs) are nano-scale structures produced by cells that transport biological substances for intercellular communication. The tetraspanins CD9, CD81, and CD63 are crucial to EV biogenesis and function. This study uses CRISPR-Cas9 system to knock out (KO) CD9, CD63, and CD81 in HEK293T cells. The goal is to investigate the role of these tetraspanins in EV bioengineering with the hypothesis that repressing endogenous production may increase the availability of exogenously introduced tetraspanin-fusion constructs and increase engineered EV production. Firstly, it is observed that individually knocking out a tetraspanin does not significantly affect EV formation. However, when all three tetraspanins are simultaneously knocked out, there is a marked decrease in EV production, as measured by nanoparticle tracking analysis (NTA). Secondly, upon reintroduction of the corresponding tetraspanins fused to firefly ThermoLuc (Tluc) or neon green (mNG) into the PanKO-, CD9KO, CD63KO-, and CD81KO-cells, the engineered EVs display a significant increase in production by 50% to 70% compared to transduction of wild-type (WT) cells, as measured by luminometer and imaging flow cytometry. These findings emphasize the potential of tetraspanin KO in the bioengineering of EVs, paving the way for new therapeutic applications by enhancing production and potentially modifying their cargo.

bioengineering↗

Systemic Inflammation Modulates Clearance and drives Extra-Hepatic Distribution of Extracellular Vesicles

Extracellular vesicles (EVs) are promising vehicles for targeted therapeutic delivery, capable of encapsulating and transporting biomolecules to specific cells and tissues. Given that inflammation is central to many acute and chronic diseases, understanding EV biodistribution under inflammatory conditions is essential for therapeutic optimization. This study examines how acute systemic inflammation influences EV biodistribution, clearance, and plasma half-life, with a focus on the role of macrophages and their polarization states. Using a lipopolysaccharide (LPS)-induced inflammation model in wild-type mice and bioluminescent and fluorescent labelling of EVs, we observed that inflammation extends the plasma half-life of EVs by over 600-fold within 2 hours and 900-fold at 24 hours post-administration, leading to significant enrichment in inflamed organs, particularly the liver and spleen. Enhanced accumulation in specific tissues translated to increased targeting of immune- and epithelial cells within those organs, with notable uptake by hepatocytes in the liver. This prolonged half-life was attributed to the altered EV protein corona in inflamed tissues, which facilitates cellular association. These findings underscore the complex dynamics between EVs and immune cells under inflammatory conditions and provide critical insights for advancing EV-based therapies in chronic inflammatory diseases.

bioengineering↗

Identification of Novel Scaffold Proteins for Improved Endogenous Engineering of Extracellular Vesicles

Extracellular vesicles (EVs) are gaining ground as next-generation drug delivery modalities. Genetic fusion of the protein of interest to a scaffold protein with high EV-sorting ability represents a robust cargo loading strategy. To address the paucity of such scaffold proteins we conducted a large-scale comparative study involving 244 candidate proteins. Their EV-sorting potential was evaluated using a simple but reliable assay that can distinguish intravesicular cargo proteins from surface and non-vesicular proteins. Notably, 24 proteins with conserved EV-sorting abilities across five types of producer cells were identified. Most of these are first to be reported including TSPAN2 and TSPAN3, which emerged as lead candidates, outperforming the well-known CD63 scaffold. Importantly, these engineered EVs show promise as delivery vehicles as demonstrated by in vitro and in vivo internalization studies with luminal cargo proteins as well as surface display of functional domains. The discovery of these novel scaffolds provides a new platform for EV-based engineering.

synthetic biology↗