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The Interleukin-17 Pathway in Psoriasis and Psoriatic Arthritis: Disease Pathogenesis and Possibilities of Treatment


Psoriasis and psoriatic arthritis (PsA) are pathophysiological enigmas among rheumatic diseases. Substantial clinical advances have been made with new therapy targeting different components of the IL-17 and IL-23 pathways. At the same time, an increase in research on the topic has provided new insights into the potential functional effects of treatments on cell types, pathways, and tissues of interest. Here we review our knowledge of all IL-17 family members, their relationships with the IL-23 pathway, and the outcomes of relevant clinical trials in which different strategies for targeting these molecules have been tested in the treatment of moderate to severe psoriasis and PsA.

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Conflict of Interest

Stefan Siebert has served as a consultant for UCB and Abbvie, has received grant support from Pfizer, has received payment for development of educational presentations (including service on speakers bureaus) from Novartis and Pfizer, and has had travel and accommodation expenses covered and reimbursed by Janssen Pharmaceutica, Pfizer, and Abbvie.

Iain B. McInnes has served as a consultant for, has received payment for development of educational presentations (including service on speakers bureaus) from, and had travel and accommodation expenses covered and reimbursed by Amgen, Novartis, and Janssen Pharmaceutica. He has also received grant support from Pfizer.

Marina Frleta declares that she has no conflict of interest.

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This article does not contain any studies with human or animal subjects performed by any of the authors.

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Correspondence to Iain B. McInnes.

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This article is part of the Topical Collection on Psoriatic Arthritis

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Frleta, M., Siebert, S. & McInnes, I.B. The Interleukin-17 Pathway in Psoriasis and Psoriatic Arthritis: Disease Pathogenesis and Possibilities of Treatment. Curr Rheumatol Rep 16, 414 (2014).

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  • Psoriatic arthritis
  • Psoriasis
  • Interleukin-17
  • IL-17
  • Interleukin-23
  • IL-23
  • Biologic agents
  • Pathogenesis
  • Treatment