IL17A and systemic sclerosis: Despite the work of Yang et al., which showed that, in dermal fibroblasts of SSc patients, the blockage of IL-17 diminished the expression of Col(lagen) I and III induced by the supernatants of SSc peripheral blood mononuclear cells (PBMCs) and Th17 cells [25]; the profibrotic role of IL-17 was not observed in isolated human fibroblasts.