The inflammatory proteome of hidradenitis suppurativa skin is more expansive than that of psoriasis vulgaris.

Abstract

BACKGROUND\nWhile hidradenitis suppurativa (HS) shares some transcriptomic and cellular infiltrate features with psoriasis, their skin proteome remains unknown.\n\n\nOBJECTIVE\nTo define and compare inflammatory protein biomarkers of HS and psoriasis skin.\n\n\nMETHODS\nWe assessed 92 inflammatory biomarkers in HS (n=13), psoriasis (n=11) and control skin (n=11) using Olink high-throughput proteomics. We also correlated HS skin and blood biomarkers using proteomics and RNA-sequencing.\n\n\nRESULTS\nWe identified 57 differentially expressed proteins (DEPs) in lesional psoriasis and 64 DEPs in lesional HS skin, compared to healthy controls. Both HS and psoriasis lesional skin demonstrated a significant upregulation of Th1 and Th17 proteins. Healthy-appearing perilesional HS skin had 63 DEPs compared to healthy controls. Nonlesional HS and psoriasis skin had 24 and 7 DEPs, respectively, compared to healthy controls. TNF and 8 other proteins were significantly correlated with clinical severity in perilesional skin (2cm from a nodule).\n\n\nLIMITATIONS\nInclusion of only moderate-to-severe patients and the cohort size.\n\n\nCONCLUSION\nHS has a higher inflammatory profile and is more diffusely distributed versus psoriasis. Proteins correlated with disease severity are potential disease mediators. Perilesional skin is comparably inflamed to lesional skin, suggesting the need to treat beyond skin nodules.