Proteomic analysis from skin swabs reveals a new set of proteins identifying skin impairment in atopic dermatitis

Atopic Dermatitis (AD) is a common inflammatory skin disease characterized by skin and systemic inflammation, and barrier dysfunction. Herein, we investigate the proteomic profile of AD skin barrier to identify a unique signature with an easy‐performed sampling approach. We enrolled 8 moderate‐to‐severe AD patients and 8 age‐ and gender‐matched healthy controls. Swabs were obtained from non‐lesional skin of retroauricular area and antecubital fold. Peptide mixtures obtained through protein precipitation and in‐solution digestion were analysed using NanoLC‐MS/MS. Label‐free quantification and statistical analysis were conducted in MaxQuant and Perseus. Bioinformatics analysis was performed using Gene Ontology and STRING. We identified 908 proteins and 35 differentially expressed proteins were selected (fold change 2, FDR