For example, TNF has a role in the apoptosis of RPE and photoreceptor apoptosis in murine cytomegalovirus retinitis [54], and Takahashi et al. [55] concluded that TNF has a role in RPE epithelial-mesenchymal transition (discussed below in terms of TGF-β genes). Here, TGFB1 is linked to cytomegalovirus retinitis.