{
  "abstract": "Introduction Patients with inflammatory bowel disease (IBD) are highly susceptible to Clostridioides difficile infection (CDI), triggering severe flares, hospitalisation and mortality. Faecal microbiota transplantation studies demonstrated microRNA (miRNA)-23a-3p and miRNA-150-5p confer cytoprotective effects against C. difficile toxins by targeting IL-12B and IL-18, respectively. Direct miRNA therapy requires stable carriers enabling cellular uptake and controlled colonic release. We evaluated poly (β-amino ester; PBAE) nanoparticles delivering miRNA-23a-3p and miRNA-150-5p to restore barrier integrity.Methods PBAE polymers synthesised from 1,6-hexanediol diacrylate and 4-aminobutanol were complexed with miRNA-23a-3p and miRNA-150-5p at 128:1 w/w ratio. Nanoparticle characterisation included dynamic light scattering and zeta-potential analysis. Barrier protection was assessed in Caco-2/TC-7 cells via transepithelial electrical resistance (TEER) and fluorescein-dextran permeability following C. difficile toxins TcdA/TcdB, lipopolysaccharide (LPS), heat-labile enterotoxin B subunit, candidalysin and ochratoxin A challenge. Colon-on-chip platforms with primary human colonoids and intestinal endothelial cells evaluated barrier function and cytoarchitecture. C57BL/6 mice received intracolonic nanoparticles every 2 days for 4 doses. Colonic miRNA levels were quantified by RT-qPCR and in situ hybridisation. Liver-on-chip models assessed potential hepatotoxicity following simulated systemic administration.Results Both miRNAs were downregulated in CDI and chronic dextran sulfate sodium-colitis models. Pathway analysis of predicted targets (N=1,008; 41 shared) implicated epithelial adherent junction signalling and TNF-α, IL-6, IL-1β, IFN-γ pathways. PBAE nanoparticles achieved efficient uptake, ­elevating intracellular miRNA-23a-3p and miRNA-150-5p without cytotoxicity. Combinatorial delivery, not individual miRNAs, preserved TEER and reduced permeability against all colitogenic toxins (p<0.05). Colon-on-chip models confirmed LPS-disrupted barrier restoration and preserved E-cadherin and VE-cadherin expression. Intracolonic administration increased mucosal miRNA levels in colonic epithelial cells without inflammation, systemic elevation or multi-organ toxicity. Liver-on-chip studies demonstrated preserved hepatocyte function.Conclusions PBAE-delivered miRNA-23a-3p and miRNA-150-5p synergistically protect intestinal barrier integrity against inflammatory and microbial insults relevant to IBD and CDI. The formulation demonstrates favourable safety profiles in advanced human organ-on-chip models and in vivo. These findings support further development of miRNA-based nanoparticle therapeutics as a novel treatment strategy for IBD complicated by CDI, offering targeted barrier protection without systemic toxicity.",
  "authors": [
    {
      "affiliations": [
        "NIHR Nottingham Biomedical Research Centre, University of Nottingham, Nottingham, United Kingdom",
        "Nottingham Digestive Diseases Centre, Translational Medical Sciences, School of Medicine, University of Nottingham, Nottingham, United Kingdom"
      ],
      "name": "Tanya Monaghan"
    },
    {
      "affiliations": [
        "School of Pharmacy, University of Nottingham, Nottingham, United Kingdom"
      ],
      "name": "Rahman Khosravi"
    },
    {
      "affiliations": [
        "Department of Biosciences, Centre for Systems Health and Integrated Metabolic Research (SHiMR), School of Science and Technology, Nottingham Trent University, Nottingham, United Kingdom",
        "John van Geest Cancer Research Centre, Centre for Systems Health and Integrated Metabolic Research (SHiMR), School of Science & Technology, Nottingham Trent University, Nottingham, United Kingdom"
      ],
      "name": "Maria Hatziapostolou"
    },
    {
      "affiliations": [
        "Department of Biosciences, Centre for Systems Health and Integrated Metabolic Research (SHiMR), School of Science and Technology, Nottingham Trent University, Nottingham, United Kingdom",
        "John van Geest Cancer Research Centre, Centre for Systems Health and Integrated Metabolic Research (SHiMR), School of Science & Technology, Nottingham Trent University, Nottingham, United Kingdom"
      ],
      "name": "Fisentzos Floras"
    },
    {
      "affiliations": [
        "NIHR Nottingham Biomedical Research Centre, University of Nottingham, Nottingham, United Kingdom",
        "Nottingham Digestive Diseases Centre, Translational Medical Sciences, School of Medicine, University of Nottingham, Nottingham, United Kingdom"
      ],
      "name": "Madeline Berrow"
    },
    {
      "affiliations": [
        "UCL School of Pharmacy, University College London, Nottingham, United Kingdom"
      ],
      "name": "Benjamin Fiedler"
    },
    {
      "affiliations": [
        "Department of Biosciences, Centre for Systems Health and Integrated Metabolic Research (SHiMR), School of Science and Technology, Nottingham Trent University, Nottingham, United Kingdom"
      ],
      "name": "Sarah Kuehne"
    },
    {
      "affiliations": [
        "School of Pharmacy, University of Nottingham, Nottingham, United Kingdom"
      ],
      "name": "David Scurr"
    },
    {
      "affiliations": [
        "Department of Biological Sciences, Clemson University, Clemson, USA"
      ],
      "name": "Anna Seekatz"
    },
    {
      "affiliations": [
        "School of Pharmacy, University of Nottingham, Nottingham, United Kingdom"
      ],
      "name": "Cameron Alexander"
    },
    {
      "affiliations": [
        "UCL School of Pharmacy, University College London, Nottingham, United Kingdom"
      ],
      "name": "Pratik Gurnani"
    },
    {
      "affiliations": [
        "Department of Biosciences, Centre for Systems Health and Integrated Metabolic Research (SHiMR), School of Science and Technology, Nottingham Trent University, Nottingham, United Kingdom",
        "John van Geest Cancer Research Centre, Centre for Systems Health and Integrated Metabolic Research (SHiMR), School of Science & Technology, Nottingham Trent University, Nottingham, United Kingdom"
      ],
      "name": "Christos Polytarchou"
    }
  ],
  "title": "P178 Poly (β-amino ester) nanoparticle delivery of microRNA-23a-3p and microRNA-150-5p protects intestinal barrier function against colitogenic toxins",
  "uid": "6d0b2d09-e8e1-5b3d-b6ab-ffa6255d5833"
}