pSIM: A Next Generation In Vitro mRNA Potency Assay

pSIM: A Next Generation In Vitro mRNA Potency Assay | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article pSIM: A Next Generation In Vitro mRNA Potency Assay Jiang Qian, Marissa Fox, Zhijun Cao, Hima Sapa, Zhichun Wang, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8408033/v2 This work is licensed under a CC BY 4.0 License Status: Posted Version 2 posted You are reading this latest preprint version Show more versions Abstract Potency testing for mRNA–lipid nanoparticle (LNP) vaccines remains challenging due to complex cell-based mechanisms and dependence on strain-specific antibodies. Here, we introduce a next-generation in vitro mRNA potency assay named as pSIM, pulsed stable isotope labeling by amino acids in cell culture (SILAC) Internal Dosing Control (IDC) Mass Spectrometry (MS). The pSIM assay co-processes test and reference LNPs enabling EC50-based or dosing-control–normalized linear slope readouts. We demonstrate applicability across monocistronic and multivalent self-amplifying mRNA constructs for influenza and SARS‑CoV‑2, show a correlation between in vitro potency and in vivo neutralization in mice, and establish stability‑indicating performance under heat stress, real-time storage, freeze–thaw and RNA–lipid adduct formation. The assay was co-qualified for QC implementation and supports phase‑appropriate release and stability testing. Biological sciences/Biological techniques/Analytical biochemistry Biological sciences/Biochemistry/RNA Full Text Additional Declarations The authors declare no competing interests. Supplementary Files pSIMSupplementalMolecularTherapy02Feb26.pdf pSIM: A Next Generation In Vitro mRNA Potency Assay Cite Share Download PDF Status: Posted Version 2 posted You are reading this latest preprint version Show more versions Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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