Expression of the IL-23/Th17 pathway in lesions of hidradenitis suppurativa

• Published in: Journal of the American Academy of Dermatology Vol. 65; no. 4; pp. 790 - 798
• Main Authors: Schlapbach, Christoph, MD, Hänni, Tanja, MD, Yawalkar, Nikhil, MD, Hunger, Robert E., MD, PhD
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Inc 01.10.2011; Elsevier
• Subjects: Adult; Biological and medical sciences; Dermatology; Female; hidradenitis suppurativa; Hidradenitis Suppurativa - metabolism; Hidradenitis Suppurativa - pathology; Humans; IL-12; IL-17; IL-23; Interleukin-12 - biosynthesis; Interleukin-17 - biosynthesis; Interleukin-23 - biosynthesis; macrophages; Macrophages - metabolism; Male; Medical sciences; Middle Aged; RNA, Messenger - metabolism; Skin involvement in other diseases. Miscellaneous. General aspects; T-Lymphocytes, Helper-Inducer - metabolism; Th17; OCT; IL; real-time polymerase chain reaction; hidradenitis suppurativa; HS; optimal cutting temperature compound; IL-12; IL-23; TNF; macrophages; T helper (cell); Th; tumor necrosis factor; RT-PCR; IL-17; toll-like receptor; glyceraldehyde-3-phosphate dehydrogenase; TLR; interleukin; Th17; GAPDH; Skin disease; Lesion; Hidradenitis suppurativa; Dermatology; Sweat gland disease
• ISSN: 0190-9622; 1097-6787
• DOI: 10.1016/j.jaad.2010.07.010

Background Hidradenitis suppurativa is a debilitating chronic disease primarily affecting intertriginous skin of the axillae, perineum, and inframammary regions. The pathogenesis of this inflammatory disease is still poorly understood. Recently, increased attention has been paid to the role of the immune system. Objective Since the interleukin 12 (IL-12)/T helper 1 (Th1) and the IL-23/Th17 pathways are believed to be crucially involved in the pathogenesis of multiple chronic inflammatory diseases, we investigated the expression and cellular source of IL-12, IL-23, and IL-17 in hidradenitis suppurativa. Methods Ten patients with hidradenitis suppurativa were included in the study. Tissue samples were obtained from lesional skin and compared with healthy skin as a control. Expression of IL-12, IL-23, and IL-17 was analyzed by semiquantitative real-time polymerase chain reaction and immunohistochemistry, and the cellular source of these cytokines was determined by double immunofluorescence. Results IL-12 and IL-23 were found to be abundantly expressed by macrophages infiltrating papillary and reticular dermis of lesional skin. In accordance with the high expression of IL-23 and its important role in the development of T helper 17 (Th17) cells, IL-17-producing T helper cells were found to distinctly infiltrate lesional dermis. Limitations The sample size was small. Conclusions Our findings suggest that the IL-23/Th17 pathway is expressed in hidradenitis suppurativa and further support involvement of the immune system. Moreover, targeting the IL-12/IL-23-common subunit p40 with novel monoclonal antibodies may represent a new option for the treatment of this recalcitrant disease.