{
  "abstract": "Background Recombinant vesicular stomatitis virus (VSV) is a promising vaccine platform due to its rapid production, strong immunogenicity, and self-amplifying RNA properties. However, its broad application is limited by the cytotoxic effects of the matrix (M) protein, which causes cytopathic effects (CPE) and raises safety concerns in vulnerable populations. This project aims to develop a safer, higher-capacity ‘mini-VSV’ platform by genomically truncating VSV, reducing M protein toxicity, and enhancing rescue efficiency for improved mRNA delivery and multi-valent vaccine development.Methods The project employs three key strategies:Genome Truncation: Constructing a ‘mini-VSV’ by deleting the N, P, G, and L genes while retaining the essential M gene (VSVΔNPGL-M) to increase foreign gene capacity and reduce intrinsic cytotoxicity.Ribozyme Optimization: Screening and incorporating high-efficiency hammerhead ribozymes flanking the genomic plasmid to improve the precision of RNA cleavage and significantly boost viral rescue efficiency for scalable production.Safety Engineering: Introducing premature stop codons into the M gene and utilizing an unnatural amino acid (UAA) system during virus rescue. This allows functional M protein incorporation only during production, while infected host cells fail to express M protein, thereby ablating CPE in vivo.Platform Validation: Developing and evaluating a bivalent COVID-19/influenza vaccine using the optimized mini-VSV platform, assessing immunogenicity (cellular/humoral) and protective efficacy in mouse challenge models.Results Successful rescue of a replication-competent mini-VSV was achieved, confirming M gene necessity for rescue.Replacing the 5’ ribozyme with a hammerhead ribozyme significantly increased mini-VSV rescue efficiency.A functional UAA system was established in mammalian cells, enabling efficient stop-codon suppression verified via GFP(TAG) reporter.Initial screening identified potential M protein stop-codon sites compatible with virus rescue using the UAA system.Conclusions This project innovatively integrates genomic minimization, ribozyme engineering, and UAA-mediated conditional protein expression to create a next-generation VSV vector platform. The optimized mini-VSV is expected to exhibit enhanced safety (reduced CPE), higher payload capacity, and scalable production efficiency. Successful development of a bivalent COVID-19/Influenza vaccine will validate this platform’s potential for rapid response to emerging infectious diseases and cancer immunotherapy.Consent Written informed consent was obtained from the patient for publication of this abstract and any accompanying images. A copy of the written consent is available for review by the Editor of this journal.",
  "authors": [
    {
      "affiliations": [
        "Lingang Laboratory, Minhang District, Shanghai, China"
      ],
      "name": "He Zhang"
    },
    {
      "affiliations": [
        "Lingang Laboratory, Minhang District, Shanghai, China"
      ],
      "name": "Xueping Gao"
    },
    {
      "affiliations": [
        "Lingang Laboratory, Minhang District, Shanghai, China"
      ],
      "name": "Xiangyu Ge"
    },
    {
      "affiliations": [
        "Lingang Laboratory, Minhang District, Shanghai, China"
      ],
      "name": "Xia Zhang"
    },
    {
      "affiliations": [
        "Lingang Laboratory, Minhang District, Shanghai, China"
      ],
      "name": "Lei Jin"
    }
  ],
  "title": "1174 UAA-regulated M protein in mini-VSV for safer vaccines",
  "uid": "bcd7fbdc-21e1-570c-a81c-9a9fd45abb71"
}