Taking into account that CyPA is the ligand of EMMPRIN, that this binding is able in activating EMMPRIN, and that CyPA levels were higher in MFS patients’ plasma as well as in conditioned medium of MFS-VSMC after AngII stimulation, we next evaluated the direct effect of the exogeneous CyPA administration on MFS-VSMC. The gene discussed is BSG; the disease is Marfan syndrome.