The utility of multimodal imaging platforms to identify antiviral inhibitors to influenza A virus infection

Orr, Lauren (2025) The utility of multimodal imaging platforms to identify antiviral inhibitors to influenza A virus infection. PhD thesis, University of Glasgow.

Abstract

Globally, there are approximately one billion cases of influenza annually, including 3-5 million severe respiratory infections and over 290,000 fatalities. Influenza A viruses (IAVs) have historically caused multiple pandemics, and the continued spillover of highly pathogenic avian IAV into the human population poses a significant public health threat. The rapid development and deployment of effective therapeutics against IAV are crucial for pandemic preparedness. However, the emergence of drug-resistant IAV strains from the use of current antiviral inhibitors necessitates the development of new classes of inhibitors. Conventional in vitro antiviral screening assays predominantly rely on 2D immortalised cell lines, though they poorly reflect the microenvironment of the human lung and often demonstrate drug efficacy that does not translate well to complex animal models or clinical trials. Here, we employed primary human bronchial epithelial (HAEC-b) cells in both 2D and 3D culture systems to assess the efficacy of inhibitors against IAV using advanced imaging platforms. 2D antiviral screening assays revealed significant variability in inhibitor efficacy between immortalised canine kidney (MDCK) cells, immortalised primary human bronchial epithelial (HBEC3-KT) cells, and HAEC-b cells. Established IAV antivirals, favipiravir and oseltamivir, exhibited reduced efficacy in HBEC3-KT and HAEC-b cells relative to MDCK cells. Given that host directed antivirals are less likely to produce drug resistant mutants, we investigated the antiviral potential of epigenetic inhibitors. Two repurposed cancer drugs, CM272 and CM579, demonstrated inhibition of IAV replication across all cell types, achieving complete viral inhibition in HAEC-b cells at a concentration of 10 µM, whilst maintaining cell viability. Additionally, we established two 3D air-liquid interface (ALI) models by differentiating HAEC-b cells on novel bioprinted scaffolds and Transwell inserts. These models, combined with advanced imaging techniques, enabled us to visualise the spatial localisation of IAV replication within the native tissue architecture. Favipiravir was shown to inhibit IAV replication and alter the spatial distribution of viral populations, potentially in a donor-dependent manner. Collectively, these findings underscore the importance of screening antiviral inhibitors in biologically relevant in vitro models and highlight the potential of repurposed epigenetic inhibitors as host-directed therapies against IAV.

• Item Type: Thesis (PhD)
• Qualification Level: Doctoral
• Subjects: Q Science > QR Microbiology > QR180 Immunology; Q Science > QR Microbiology > QR355 Virology
• Colleges/Schools: College of Medical Veterinary and Life Sciences > School of Infection & Immunity > Centre for Virus Research
• Supervisor's Name: Boutell, Dr. Chris and Gadegaard, Professor Nikolaj
• Date of Award: 2025
• Depositing User: Theses Team
• Unique ID: glathesis:2025-85335
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 14 Jul 2025 09:58
• Last Modified: 14 Jul 2025 09:59
• Thesis DOI: 10.5525/gla.thesis.85335
• URI: https://theses.gla.ac.uk/id/eprint/85335