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Biology subjects

Troyer, Z.

Publications and source records attributed to Troyer, Z..

3 recordsLinked to original sources

Isolation and Characterization of Extracellular Vesicles from Mouse Retina Tissue

This protocol provides a standardized workflow for the isolation of extracellular vesicles (EVs) from mouse retinal tissue, and includes an assessment of EV size and concentration, marker expression, and EV visualization in accordance with the International Society for Extracellular Vesicles Minimal Information for Studies of Extracellular Vesicles (MISEV) guidelines. Most retinal EV studies rely on cell culture, which may not fully capture in vivo biology. Our approach more accurately reflects physiological and pathological EV states in vivo by enabling the extraction of EVs from intact retinal tissue. This method addresses a key gap in the field by providing a reproducible and rigorous protocol for studying retinal EVs in a biologically relevant context.

cell biology↗

Human endogenous retrovirus envelope proteins alter extracellular vesicle cellular interactions and biodistribution

Extracellular vesicles (EVs) are versatile therapeutic candidates due to biological roles in intercellular communication and amenability to bioengineering. Compared with lipid nanoparticles (LNPs), native or surface-modified EVs may have favorable immunogenicity and biodistribution profiles. However, when administered intravenously (IV), EVs are rapidly cleared and accumulate mostly in the liver and spleen. With the goal of modifying EV biodistribution, we engineered EVs to display the human endogenous retrovirus (HERV) envelope glycoprotein Syncytin-1, an SLC1A5-binding fusogenic viral protein essential for syncytiotrophoblast formation in pregnancy. Here, we comprehensively characterize engineered Syncytin-1+ EVs, examine their interactions with cells in vitro, and assay biodistribution, immunogenicity, and pharmacokinetics ex vivo and in vivo in non-human primates. IV-administered Syncytin-1+ EVs are well tolerated, persist in the blood stream, and have altered organ biodistribution compared with unmodified EVs, suggesting therapeutic potential of Syncytin-1+ EVs at specific sites.

bioengineering↗

Simultaneous protein and RNA analysis in single extracellular vesicles, including viruses: SPIRFISH

Interest in using nanoparticles for delivery of therapeutic RNA has been steadily growing, provoking a need to precisely understand their structure and contents. Single-particle and single-molecule analysis techniques provide snapshots of single biological nanoparticles, including viruses, liposomes, and extracellular vesicles (EVs). While existing methods primarily focus on protein detection, RNA delivery is becoming increasingly prevalent. A method to simultaneously detect protein and internal RNA in the same particle would reveal variability in size, structure, and RNA packaging efficiency, enabling optimization of nanoparticle delivery. Here, we introduce SPIRFISH, a high-throughput method for single-particle protein and RNA analysis, combining single particle interferometric reflectance imaging sensor (SP-IRIS) with single-molecule fluorescence in-situ hybridization (smFISH). Using SPIRFISH, we detect HIV-1 envelope protein and genomic RNA within single infectious virions, allowing resolution against EV background and noninfectious virions. We further show that SPIRFISH can be used to detect specific RNA within EVs. SPIRFISH should enable single particle analysis of a broad class of RNA-containing nanoparticles. Teaser: A new single particle analysis technique simultaneously detects specific RNA and protein in biological nanoparticles.

molecular biology↗