The Woronoff Ring in Psoriasis and the Mechanisms of Post-inflammatory Hypopigmentation

Prinz, Jörg Christoph (2020): The Woronoff Ring in Psoriasis and the Mechanisms of Post-inflammatory Hypopigmentation. In: Acta Dermato-Venereologica, Bd. 100: S. 65-68

Abstract

The Woronoff ring is a ring-like hypopigmentation zone around regressing psoriasis lesions. Although it was first described more than 100 years ago, its aetiology has remained a mystery. Recent insights into the pathogenesis of psoriasis can now explain the origin of the Woronoff ring. Psoriasis involves an HLA-class I-restricted autoimmune response of CD8(+) T cells against melanocytes in the epidermis. The pathogenic CD8(+) T cells are not cytotoxic, but are characterized by the production of interleukin-17, interleukin-22 and tumour necrosis factor-alpha. Interleukin-17 and tumour necrosis factor-alpha act synergistically on melanocytes by increasing proliferation while inhibiting melanogenesis. This reduces the cellular melanin content despite an increased number of melanocytes in psoriatic lesions. As a consequence, during healing the prior influence of interleukin-17 and tumour necrosis factor-alpha, despite the increased density of melanocytes, leaves a hypopigmented zone at the edge of regressing psoriasis lesions, which becomes visible as the Woronoff ring. This mechanism can explain a long-discussed puzzling phenomenon in dermatology.

• Dokumententyp: Zeitschriftenartikel
• Fakultät: Medizin
• Themengebiete: 600 Technik, Medizin, angewandte Wissenschaften > 610 Medizin und Gesundheit
• ISSN: 0001-5555
• Sprache: Englisch