Systemic sclerosis (SSc) is an autoimmune disease characterized by skin and internal organ. Over 90% of patients with SSc are positive for autoantibodies. In addition, the serum levels of B cell activating factor, a potent B cell stimulator, are correlated with SSc severity and activity. Thus, B cells play an important role in SSc pathogenesis. However, two opposing B cell subsets exist: effector B cells (Beffs) and regulatory B cells (Bregs). Interleukin (IL)-6–producing Beffs have been shown to promote scleroderma in a mouse model, whereas IL-10–producing Bregs inhibit sclerodoma development. In the present study, we investigated the clinical association of Beffs and Bregs in patients with SSc. In this study, we investigated the association of B cell balance and the skin fibrosis in SSc patients.The blood levels of IL-6–producing Beffs and IL-10–producing Bregs were measured in 30 Japanese patients with SSc and 21 healthy subjects by flow cytometry. The frequency of IL-6–producing Beffs in the blood was significantly (P< 0.0001) elevated in patients with SSc (median 56.2%, range 35.3–81.3%)compared with that in healthy controls (median 41.3%, range 21.0–61.3%). In contrast, the frequency of IL-10–producing Bregs in the blood was significantly (P < 0.05) decreased in patients with SSc (median 1.4%, range 0.5–2.8%)compared with that in healthy controls (median 2.0%, range 1.1–3.8%). The Beff/Breg ratio was significantly increased in patients with SSc. In addition, the Beff/Breg ratio was positively correlated with the skin score and interstitial lung disease extent.These results suggest that dysregulation of effector and regulatory B cell balance contributes to SSc pathogenesis. In addition, Beff/Breg ratio have the possibility to be a new therapeutic target.

ESDR052 - Cytokine-producing B cell balance associated with skin fibrosis in patients with systemic sclerosis

The scientific meeting of the European Society for Dermatological Research (ESDR) is held yearly, usually in September. With an international attendance of more than 1000 skin scientists from around the globe, the four-day event includes short oral presentations from peer-reviewed abstracts, keynote lectures from international experts, sponsored symposia, satellite programs, educational events as well as an important focus on posters, networking and building collaborations amongst scientists. For more information about this year’s meeting visit our website.