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Ye, J. Z.

Publications and source records attributed to Ye, J. Z..

3 recordsLinked to original sources

MuteFree: A novel AAV vector system featuring mutation-free ITRs

Instability of the inverted terminal repeats (ITRs) in AAV transfer plasmids has long hindered consistent and efficient production of therapeutic AAV vectors. The palindromic, GC-rich ITR sequence readily forms secondary structures, making them highly mutable in transfer plasmids. Indeed, a recent survey observed mutated ITRs in [~]40% of AAV transfer plasmids from labs around the world. Conventional strategies to mitigate this issue - such as using specialized E. coli strains, suboptimal culture conditions, or modified ITR sequences - have limited effect and often compromise plasmid and AAV yield. Here, by combinatorial optimization of the plasmid backbone structure and ITR flanking sequences, we established MuteFree, an AAV transfer plasmid system that eliminated ITR mutations for both single-stranded AAV (ssAAV) and self-complementary AAV (scAAV). Specifically, MuteFree reduced ITR mutation rates from a range of 32-100% in various transfer plasmids tested to 0% after serial passage of host E. coli for >160 population doublings. Moreover, in three GMP-grade AAV plasmid manufacturing projects initially cancelled due to severe and incurable ITR mutations, replacing conventional backbone with MuteFree completely solved the problem, reducing mutation occurrence to zero under standard GMP manufacturing conditions. Notably, MuteFree supports the packaging of potent AAV virus. The MuteFree system thus presents a robust solution to ITR instability, enabling high-fidelity and high-yield AAV production of AAV-based gene therapy vectors that is fully compatible with existing GMP manufacturing workflows.

molecular biology↗

miniVec: A miniaturized plasmid backbone supporting antibiotic-free and additive-free fermentation with enhanced yield and functionality

Plasmids are a foundational research reagent and a key material in biopharmaceutical manufacturing. Plasmids require a backbone for propagation in E. coli, which typically contains an antibiotic resistance gene alongside a replication origin. As plasmids increasingly enter clinical applications, concerns are raised on the safety risks of antibiotic resistance genes. Additionally, these protein-coding genes occupy long stretches of DNA that incur significant metabolic burdens on host cells, which negatively impacts plasmid manufacturability and functionality, leading to high production cost and compromised clinical efficacy. Here, we describe miniVec, a novel miniaturized plasmid backbone devoid of protein-coding sequence, and instead expresses a small RNA to provide constant selective pressure capable of sustaining high plasmid copy numbers in plain culture media devoid of antibiotics or other chemical additives. This simplifies large-scale fermentation and greatly increases plasmid yield. Notably, miniVec confers enhanced functionality in a variety of applications such as chemical transfection, electroporation, virus packaging, transposon-or CRISPR-mediated genome integration, and in vivo naked DNA transfection and vaccination, while exhibiting no detectable immunogenicity or toxicity. These advantages establish miniVec as the next-generation plasmid platform for clinical applications, featuring improved safety that aligns with regulatory expectations, enhanced manufacturability leading to much higher yield and dramatic cost reduction, and augmented functionality in diverse applications.

bioengineering↗

Proteomics dissection of cardiac protein profiles of humans and model organisms

The study of human cardiac pathologies often relies on research conducted in model organisms to gain molecular insight into disease and to develop novel treatment strategies; however, translating findings from model organisms back to human can present a significant challenge, in part due to a lack of knowledge about the differences across species in cardiac protein abundances and their interactions. Here we set out to bridge this knowledge gap by presenting a global analysis of cardiac protein expression profiles in humans and commonly used model organisms. Using quantitative mass spectrometry-based proteomics, we measured the abundance of ~7,000 proteins in samples from the separate chambers of human, pig, horse, rat, mouse and zebrafish hearts. This knowledgebase of cardiac protein signatures is accessible through an online database at: atlas.cardiacproteomics.com. Quantitative comparison of the protein profiles support the pig as model organism of choice for arrhythmogenic right ventricular cardiomyopathy whereas comparison of profiles from the two-chambered zebrafish heart suggests a better resemblance to the right side of mammalian hearts. This proteomics resource facilitates translational prospect of cardiac studies from model organisms to humans by enabling direct comparison of disease-linked protein networks across species.

systems biology↗