FRI0355 Il-17a up-regulation in peripheral blood mononuclear cells co-cultured with autologous skin fibroblasts is associated with down-regulation of pro-fibrotic mediators and increased fibroblast apoptosis

Background IL-17A has been implicated in the pathogenesis of systemic sclerosis (SSc) (1). We previously showed that skewed peripheral blood mononuclear cells (PBMCs) from SSc patients can induce Fas-mediated apoptosis in co-cultured autologous skin fibrobalsts (2). Objectives We therefore aimed to investigate IL-17A expression and effects in these co-cultures. Methods PBMCs and skin fibroblasts from 5 dcSSc patients with disease duration Results IL17A mRNA in co-cultured PBMCs was increased by 11.5 fold (p Conclusions Our results support the role of IL-17A in the pathogenesis of SSc. Furthermore, here we first show that IL-17A up-regulation in co-cultured PBMCs might play antifibrotic effects in autologous skin fibroblasts and might be implicated in fibroblast apoptosis, interphering with the FAS/FASL pathway. References Brembilla NC, Chizzolini C. T cell abnormalities in systemic sclerosis with a focus on Th17 cells. Eur Cytokine Netw 2012; 23: 128–39. De Palma R et al. Peripheral T cells from patients with early systemic sclerosis kill autologous fibroblasts in co-culture: is T-cell response aimed to play a protective role? Rheumatology (Oxford) 2010; 49: 1257–66. Disclosure of Interest None declared