STAT3 and systemic sclerosis: We demonstrated that NE-induced IL-6/IL-6 receptor trans-signaling via STAT3 activation increased collagen type I production in SSc fibroblasts, suggesting that NE induces IL-6 secretion from dermal fibroblasts and has both paracrine and autocrine effects on various cells, including dermal fibroblasts, T cells and B cells, that stimulate skin fibrosis in the setting of SSc.