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Contribution of the IL-17 Pathway to Psoriasis and Psoriatic Arthritis

  • Psoriatic Arthritis (O FitzGerald and P Helliwell, Section Editors)
  • Published:
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Abstract

Investigators have accrued compelling evidence that the IL-17 pathway is central to the pathogenesis of psoriasis and psoriatic arthritis. The evidence comprises genome-wide association studies (GWAS), data from experimental murine models and findings from in vitro studies on patients’ cells or tissue biopsies. More recently, the success of drugs blocking the IL-17 pathway in treating both psoriasis (PsO) and psoriatic arthritis (PsA) confirms that IL-17 is a clinically relevant therapeutic target. However, there remain many unanswered questions: is PsA simply an extension of PsO from the skin to the synovial tissue or are there differences in the underlying pathogenesis of these diseases? Which cell type represents the primary source of IL-17 in PsO and PsA? And how are these cells regulated? This review outlines the IL-17 pathway, summarises the evidence supporting its role in PsO and PsA and discusses recent data that may help to address these yet unresolved questions.

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LE Durham declares no conflict of interest.

LS Taams declares the receipt of speaker fees and research support from Novo Nordisk A/S, GSK and UCB.

BW Kirkham declares the receipt of research support from UCB, Roche, and Consultant/Speaker fees from Abbott, BMS, Celgene, Janssen, MSD, Novartis, Pfizer, Roche and UCB.

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This article is part of the Topical Collection on Psoriatic Arthritis

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Durham, L.E., Kirkham, B.W. & Taams, L.S. Contribution of the IL-17 Pathway to Psoriasis and Psoriatic Arthritis. Curr Rheumatol Rep 17, 55 (2015). https://doi.org/10.1007/s11926-015-0529-9

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