PTX3 and systemic sclerosis: The level of acute phase response protein pentraxin-3 (PTX3), which act as an antiangiogenic factor by binding to fibroblast growth factor-2 (FGF-2) and inhibiting FGF-2-dependent neovascularization and extracellular matrix (ECM) proliferation is increased, while the level of fibroblast growth factor-2 (FGF-2) is decreased in SSc-PAH (Rusnati et al., 2004).