{
  "abstract": "Introduction The gut barrier is fundamental to human health and regulates the passage of molecules from the intestine into the blood stream. The permeability of the gut barrier is impaired in numerous health disorders including coeliac disease, inflammatory bowel disease (IBD), liver disease, and environmental enteropathy (EE, a multifaceted breakdown in gut function associated with undernutrition). Importantly, the role of the gut barrier in the above conditions is still not fully understood. Furthermore, current approaches to assess intestinal barrier function are expensive, invasive, unreliable and/or difficult to perform in certain populations. Thus, there is an urgent need for novel tests that can be deployed at scale to improve assessment and understanding of gut barrier function in EE and other diseases.Methods To begin to address these issues, we used transcutaneous fluorescence spectroscopy (TFS) to investigate intestinal barrier function in EE. TFS involves participants receiving an oral dose of a fluorescent contrast agent (fluorescein) and a wearable probe being placed on the fingertip to non-invasively assess uptake of fluorescein from the gut into the blood stream (via ‘through-the-skin’ fluorescence measurements). Volunteers were recruited in a Zambian community where EE is prevalent (n=34) and in the UK (n=17) to undergo TFS measurements in a cross-sectional study. TFS data were first compared between groups. Second, in a subset of 14 Zambian participants, TFS data were correlated with the lactulose:rhamnose (LR) test.Results TFS demonstrated significant differences in intestinal barrier function between UK and Zambian volunteers. Zambian participants exhibited higher peak fluorescence intensity (p=0.003) and area under fluorescence curves (p=0.02) than UK participants ( figure 1A), suggesting increased fluorescein permeation. Time to reach peak intensity was consistent between groups, indicating no differences in factors affecting uptake rate (e.g. gastric emptying, gut motility). Finally, fluorescence kinetics and regression analysis revealed strong correlations between TFS data and urinary recoveries of lactulose and rhamnose (Spearman’s r≥0.78, p<0.002; figure 1B).Conclusions TFS revealed differences in intestinal barrier function between EE and healthy cohorts using a rapid, sample-free methodology. Combined with exploratory results demonstrating correlation to the LR test, this implies potential to facilitate more advanced study of the role of the gut barrier in health and disease.Abstract P380 Figure 1(A) Mean (± standard deviation) TFS time courses recorded in Zambian and UK participants. Inset shows box plot of total area under curve (AUC). (B) Scatter plots showing correlation between actual percentage recoveries of lactulose and rhamnose and values predicted using TFS regression analysis.",
  "authors": [
    {
      "affiliations": [
        "The Hamlyn Centre, Institute of Global Health Innovation (IGHI), Department of Surgery & Cancer, Imperial College London, London, United Kingdom"
      ],
      "name": "Alex Thompson"
    },
    {
      "affiliations": [
        "The Hamlyn Centre, Institute of Global Health Innovation (IGHI), Department of Surgery & Cancer, Imperial College London, London, United Kingdom"
      ],
      "name": "Elena Monfort-Sanchez"
    },
    {
      "affiliations": [
        "The Hamlyn Centre, Institute of Global Health Innovation (IGHI), Department of Surgery & Cancer, Imperial College London, London, United Kingdom"
      ],
      "name": "Nilanjan Mandal"
    },
    {
      "affiliations": [
        "Tropical Gastroenterology and Nutrition Group, University of Zambia School of Medicine, Lusaka, Zambia"
      ],
      "name": "Mulima Mwiinga"
    },
    {
      "affiliations": [
        "Tropical Gastroenterology and Nutrition Group, University of Zambia School of Medicine, Lusaka, Zambia"
      ],
      "name": "Rose Banda"
    },
    {
      "affiliations": [
        "The Hamlyn Centre, Institute of Global Health Innovation (IGHI), Department of Surgery & Cancer, Imperial College London, London, United Kingdom"
      ],
      "name": "Jiacheng Xu"
    },
    {
      "affiliations": [
        "Tropical Gastroenterology and Nutrition Group, University of Zambia School of Medicine, Lusaka, Zambia"
      ],
      "name": "Monica Mweetwa"
    },
    {
      "affiliations": [
        "Tropical Gastroenterology and Nutrition Group, University of Zambia School of Medicine, Lusaka, Zambia"
      ],
      "name": "Tracy Phiri"
    },
    {
      "affiliations": [
        "Tropical Gastroenterology and Nutrition Group, University of Zambia School of Medicine, Lusaka, Zambia"
      ],
      "name": "Ian Chisenga"
    },
    {
      "affiliations": [
        "The Hamlyn Centre, Institute of Global Health Innovation (IGHI), Department of Surgery & Cancer, Imperial College London, London, United Kingdom"
      ],
      "name": "Jonathan Gan"
    },
    {
      "affiliations": [
        "The Hamlyn Centre, Institute of Global Health Innovation (IGHI), Department of Surgery & Cancer, Imperial College London, London, United Kingdom"
      ],
      "name": "Zixin Wang"
    },
    {
      "affiliations": [
        "The Hamlyn Centre, Institute of Global Health Innovation (IGHI), Department of Surgery & Cancer, Imperial College London, London, United Kingdom"
      ],
      "name": "Arjun Agarwal"
    },
    {
      "affiliations": [
        "National Phenome Centre, Section of Bioanalytical Chemistry, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, United Kingdom"
      ],
      "name": "Ash Salam"
    },
    {
      "affiliations": [
        "National Phenome Centre, Section of Bioanalytical Chemistry, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, United Kingdom"
      ],
      "name": "María Gómez-Romero"
    },
    {
      "affiliations": [
        "National Phenome Centre, Section of Bioanalytical Chemistry, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, United Kingdom"
      ],
      "name": "Lynn Maslen"
    },
    {
      "affiliations": [
        "National Phenome Centre, Section of Bioanalytical Chemistry, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, United Kingdom"
      ],
      "name": "Elena Chekmeneva"
    },
    {
      "affiliations": [
        "The Hamlyn Centre, Institute of Global Health Innovation (IGHI), Department of Surgery & Cancer, Imperial College London, London, United Kingdom"
      ],
      "name": "Ara Darzi"
    },
    {
      "affiliations": [
        "Division of Digestive Diseases, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, United Kingdom"
      ],
      "name": "Julian Marchesi"
    },
    {
      "affiliations": [
        "The Hamlyn Centre, Institute of Global Health Innovation (IGHI), Department of Surgery & Cancer, Imperial College London, London, United Kingdom",
        "School of Electronic and Electrical Engineering, University of Leeds, Leeds, United Kingdom"
      ],
      "name": "James Avery"
    },
    {
      "affiliations": [
        "Tropical Gastroenterology and Nutrition Group, University of Zambia School of Medicine, Lusaka, Zambia",
        "Blizard Institute, Queen Mary University of London, London, United Kingdom"
      ],
      "name": "Paul Kelly"
    }
  ],
  "title": "P380 Assessment of intestinal barrier function in environmental enteropathy using non-invasive fluorescence sensing",
  "uid": "d77f00e2-e55a-5f60-a581-48ecc3e1727e"
}