Oferta TFM | ID 30

Introduction

Ulcerative colitis (UC) is a chronic relapsing inflammatory bowel disease characterized by disruption of the intestinal epithelial barrier and persistent mucosal inflammation. Restoration of epithelial integrity has emerged as a primary therapeutic goal, as it is associated with sustained clinical remission and reduced risk of relapse, hospitalization, and surgery. Despite its importance, current methods to assess mucosal healing, such as endoscopy and histological biopsy, are invasive, costly, and impractical for frequent monitoring. There is a pressing need for accessible, non-invasive biomarkers that reflect intestinal barrier function and correlate with treatment response. Tight junction and cell adhesion proteins, including claudin-2, occludin, and zonula occludens-1 (ZO-1), are critical regulators of epithelial barrier integrity and have been implicated in the pathogenesis and progression of UC. These molecules represent promising targets for biomarker discovery and the development of novel diagnostic tools.

Aim and Objectives

The primary aim of this project is to evaluate tight junction proteins, claudin-2, occludin, and ZO-1, as biomarkers of intestinal barrier integrity in a murine model of experimental UC.

Methods

The project will be conducted using ex vivo tissues from a dextran sulfate sodium (DSS)-induced colitis mouse model, which recapitulates key features of human UC. Mice will be treated with clinically relevant anti-inflammatory therapies (e.g. anti-TNF biologics) to evaluate biomarker dynamics before and after intervention. Expression of claudin-2, occludin, and ZO-1 will be analyzed at the mRNA level using quantitative reverse transcription PCR (RT-qPCR), and at the protein level using Western blotting. Immunohistochemistry (IHC) will be employed to assess spatial localization and tissue-specific expression of these proteins within the colon. Histological analysis using hematoxylin and eosin staining will allow for evaluation of inflammatory cell infiltration, epithelial damage, and tissue architecture. In parallel, clinical disease progression will be monitored using the Disease Activity Index (DAI), and cytokine profiling will be performed to evaluate the inflammatory milieu and immune response to treatment.

Significance

This research addresses a critical unmet need in the management of UC: the lack of non-invasive, barrier-specific biomarkers that can reflect mucosal healing and guide therapeutic decisions. By integrating molecular, histological, clinical, and functional assessments, this project seeks to bridge the gap between bench and bedside. Ultimately, the findings may support the development of a molecular imaging agent targeting tight junction proteins, offering a novel tool to monitor disease activity and treatment efficacy in both patients and preclinical drug development.