In fact, the RPE secretes TGF-β1 and -β2, which induce various retinal pathogeneses such as PVR and ARMD, as stated above, in addition to retinal physiology, that is, RPE cell polarity is determined by TGF-β to maintain the normal physiology of the RPE [42]. Here, TGFB1 is linked to age-related macular degeneration.