Abstract
BACKGROUND: Allergic contact dermatitis (ACD) and irritant contact dermatitis (ICD) are common skin conditions with an overlapping clinical and histological appearance, but distinct underlying mechanisms. Patch testing is the gold standard for ACD diagnosis, yet the interpretation of its results may be confounded by weak and varying macroscopic reactions. OBJECTIVE: To examine whether gene transcript profiling of RNA sampled from patch tested patient skin by tape stripping (TS) could differentiate ACD from ICD and the baseline skin state (control) METHODS: Nine patients (seven females, two males; mean age 38.6 years, range 24-72 years) with confirmed ACD through patch testing were recruited. Total RNA was isolated from TS samples and relative transcript abundance was determined by quantitative real-time polymeraise chain reaction using 39 gene-specific primers. RESULTS: TS captured gene transcripts derived from diverse skin cell types, including not only keratinocytes, but also epidermal and dermal antigen-presenting cells. Among the genes analysed in transcript profiling, genes encoding epidermal barrier components and inflammatory mediators exhibited changes in transcript abundance in ACD skin compared to ICD or control skin. CONCLUSIONS: Our findings reveal the potential of skin TS for non-invasive biopsy during patch testing and molecular marker-based ACD diagnosis.