Mediators of angiogenesis and fibrosis in IgG4-related disease.

IgG4-related disease (IgG4-RD) is a rare fibro-inflammatory condition that can affect almost any organ, characterized by tumefactive lesions and often by eosinophilia and elevated serum IgG4 concentrations. The aim of the study is to analyze in IgG4-RD patients the serum levels of a group of cytokines and growth factors potentially involved in the regulation of fibrotic processes. In the sera of 12 patients affected by IgG4-RD and of 15 normal healthy subjects (NHS), pro-fibrogenic mediators (TGF-β1 and periostin) and pro- (VEGF and angiogenin-1) and anti- (endostatin and thrombospondin-1) angiogenic mediators were measured by sandwich enzyme immunoassay. Among mediators regulating fibrosis and angiogenesis, endostatin levels were significantly higher in IgG4-RD patients compared to NHS (p < 0.0001). No differences in the levels of TGF-β1, periostin, VEGF, angiogenin-1 and thrombospondin-1 were observed between groups. Our study suggests that among the mediators mainly involved in fibrosis and angiogenesis endostatin might play a role in the pathogenetic processes of IgG4-RD.