Group Leader Evotec Toulouse, Midi-Pyrenees, France
Disclosure(s):
Frederic J. Machet: No relevant disclosure to display
Introduction/Rationale: Atopic dermatitis (AD) is a chronic inflammatory skin disease driven by immune dysregulation and impaired barrier function, including altered ceramide composition. In clinical practice—especially in children—non-invasive tools such as epidermal curettage, microneedle patches, and tape stripping are widely used to monitor skin biomarkers and predict therapeutic efficacy. However, these techniques remain underused in preclinical models, where invasive biopsies are still standard, limiting longitudinal monitoring and translational relevance.
Methods: This study assessed the feasibility, safety, and translational value of a non-invasive skin surface sampling strategy to monitor immune dysregulation and barrier alterations in two murine AD models. AD-like lesions were induced by chronic oxazolone application on the back or repeated MC903 treatment on the ear. Weekly samples were collected using cotton-tipped swabs for multiplex cytokine assays and ceramide profiling, while glass beads were rolled over the skin for lipid extraction and LC-MS/MS quantification. Data from non-invasive samples were compared with full-thickness biopsies analyzed at endpoint by immunoassays and lipidomics.
Results: Repeated sampling over 20 days caused no visible damage, distress, or interference with disease progression. Key cytokines (IL-4, IL-6, TNF, IL-1β) and ceramides were consistently detectable on the skin surface and correlated with tissue levels. Ceramide profiles reflected barrier dysfunction and inflammation, supporting their value as non-invasive biomarkers.
Conclusion: This dual-parameter, minimally invasive approach enables longitudinal monitoring of both immune and barrier markers in preclinical AD models. It aligns with clinical strategies, supports the 3Rs principles and enhances the translational value of murine studies.
