TIMP4 and occult macular dystrophy: The addition of PGF2α or OMD induced a significant downregulation of TIMP3 and 4 (3D) and MMP9 (3D) and an upregulation of MMP9 (2D), or the downregulation of TIMP3 and 4 (3D) and MMP9 (3D), the upregulation of TIMP4 (2D) and MMP2 and 14 (2D), respectively.