Tolerability and Feasibility of Minimally Invasive Canine Skin Sampling: Excellent Tolerability Meets Transcriptomic Challenges.

Abstract

Background: Advances in transcriptomics have driven the demand for minimally invasive, reproducible and high-yield skin sampling methods, particularly for studying inflammatory skin diseases in companion animals.

Hypothesis/objectives: We tested tolerability, feasibility and RNA quantity and quality of three minimally invasive skin sampling techniques.

Animals: Nine privately-owned dogs, including healthy individuals and those diagnosed with canine atopic dermatitis.

Materials and methods: The tolerability and feasibility of three minimally invasive skin sampling techniques-microbiopsy (MB) collection, skin-scraping (SS) and tape-stripping (TS)-were tested in a clinical setting. RNA quantity and quality (RIN) were measured. Quality control and potential contamination were evaluated during downstream RNA sequencing.

Results: All techniques were well-tolerated, and sampling was feasible in a clinical setting. RNA yield and quality varied significantly. Microbiopsy and SS samples yielded low RNA quantities with poor integrity. Tape-stripping samples produced the highest RNA concentration and integrity (RIN 3.4-7.1) yet showed notable variability. Although initial sequencing quality thresholds were met, downstream transcriptomic analysis of the TS samples was limited by uneven degradation and suspected DNA contamination.

Conclusions and clinical relevance: Minimally invasive skin sampling methods are feasible and well-tolerated in dogs. Among the techniques evaluated, TS showed the most potential for transcriptomic applications. However, RNA quality remains a key limitation. Further refinement in sample processing and handling is essential to improve consistency and enable reliable downstream analyses in veterinary dermatological research.