Proteomic analysis of psoriatic skin lesions in a Chinese population

Psoriasis is a chronic skin disorder with undefined pathogenesis. Several biomarkers for this disease have been identified by proteomic analysis. We explored the whole-proteomic changes in 45 pairs of psoriatic and adjacent noninvolved skin tissues in a Chinese population. A total of 3686 proteins were identified, of which 3008 were quantified. A total of 102 and 124 proteins were upregulated and downregulated in lesional skin, respectively. SART1 (P = 3.55 × 10^-5) and GLTP (P = 1.54 × 10^-3) were the most significantly down- and upregulated proteins. Nearly 90% of these differentially regulated proteins exhibited the same expression trends as those in an online RNA sequencing dataset for psoriasis; 19 differentially regulated proteins exhibited a negative relationship with DNA methylation data for psoriatic lesions. The differentially expressed proteins were enriched in ribosomes, antigen processing and presentation, immune response, and IL-17 signalling pathways. This study identified multiple differentially regulated proteins in psoriatic lesions, which suggested that changes in the proteome play important regulatory roles in psoriasis-associated processes. SIGNIFICANCE: Proteomic analysis was performed in 45 pairs of psoriatic and adjacent noninvolved skin tissues in a Chinese population. More than 3000 proteins were quantified, of which 226 were differentially expressed in psoriatic skin tissues. These proteins were mainly enriched in the immune response, antigen processing and presentation and IL-17 signalling pathways, which have been reported to be associated with the pathogenesis of psoriasis.