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Kutanovas, S.

Publications and source records attributed to Kutanovas, S..

2 recordsLinked to original sources

Improved Protein Encapsulation and Delivery by Lipid Nanoparticles with Refined Ionizable Lipid Content

Efficient intracellular delivery of nucleic acids, proteins, and other biomolecules is critical to advancing therapeutic strategies and genome-editing technologies. Lipid nanoparticles (LNPs) have emerged as highly promising delivery vehicles owing to their self-assembly properties, biocompatibility, and capacity to encapsulate large molecular cargos. Their biological performance is determined largely by lipid composition, which influences particle stability, cellular uptake, membrane fusion, and intracellular trafficking. In this study, we designed and optimized LNP formulations inspired by the lipid architecture of enveloped viruses. Four distinct formulations were generated and systematically evaluated in mammalian cell culture, leading to the identification of two lead candidates with superior delivery characteristics. The biodistribution and translocation properties of these formulations were subsequently assessed using an in vitro brain endothelial barrier model to mimic brain environment. Furthermore, we demonstrated that the selected LNPs enable efficient and functional delivery of CRISPR-Cas ribonucleoprotein complexes to mammalian cells. Together, these findings underscore the potential of rationally engineered LNPs as versatile, safe, and effective non-viral delivery platforms for advanced genome-editing applications.

biochemistry↗

Integrity assay for messenger RNA in mouse and human brain samples and synaptosomal preparations

Traditionally, RNA integrity evaluation is based on ribosomal RNAs (rRNAs). Nevertheless, gene expression studies are usually focused on protein coding messenger RNAs (mRNAs). As rRNA and mRNA have significant structural and functional differences, the assumption that rRNA integrity properly represents mRNA integrity may not be accurate. Moreover, contrary to whole tissue RNA samples, subcellular preparations such as synaptosomes contain almost no rRNA, thus prohibiting the use of traditional rRNA-based methods to assess sample RNA integrity. Here we present a RT-qPCR based assay, which estimates mRNA integrity by comparing the abundance of 3 and 5 mRNA fragments in a long constitutively expressed mouse or human PGK1 mRNA. The assay was tested and validated using plasmids with cloned 3- and 5-ends of the PGK1 cDNA reflecting different ratios of 3 and 5 cDNA amplicons in partially degraded RNA samples. The accuracy of integrity score calculation was ensured by integrating a mathematical correction of qPCR results to account for the variable amplification efficiency of different primer pairs. The 5:3 assay was used to quantify RNA degradation in heat-degraded mouse and human brain tissue RNA as well as in clinical human brain RNA samples. Importantly, the expression of housekeeping genes correlated better with 5:3 integrity value than with the RIN. Finally, we were even able to use 5':3' assay to assess mRNA integrity in mouse synaptosomal preparations that lack rRNAs. We concluded that the 5:3 assay can be used as a reliable and sensitive method to evaluate mRNA integrity in mouse and human brain tissue and subcellular preparations.

molecular biology↗