demonstrated that soluble factors in the local milieu are crucial for pro-fibrotic activation of SSc macrophages (measured as secretion of CCL2, IL-6, TGFβ), arisen from circulating monocytes either stimulated with SSc sera or conditioned media from indirect co-culture with dermal SSc fibroblasts (64). The gene discussed is TGFB1; the disease is systemic sclerosis.