Fig 1: Injection with Tn leads to over production of cytokines in the retinal cells. (a) The cone-derived 661W cells treated with Tn (N=4) were harvested 1 and 8 h post injection to assess levels of Il-1ß, Il-1 R and Il-6 by qRT-PCR. Results of the experiments demonstrated that the Tn treatment induces a 3.6-fold upregulation of Il-1ß mRNA and 33% downregulation of Il-1R mRNA 1 h post treatment. (a) A 4-fold overexpression of Il-6 mRNA was observed 8 h post treatment with Tn. (b–d): Modulation of the UPR markers leads to altered cytokine's production. (b) Images of western blots obtained from the CHOP-/- and ATF4 overexpressing retinal extracts. (c) CHOP ablation in Tn-injected retinas (N=4) leads to a 46% and by 66% reduction in IL-6 and IL-1ß, respectively, at 3 days post treatment, indicating that CHOP might regulate production of these cytokines. (d) The 2.6-fold increase in ATF4 triggers pro-inflammatory IL-1ß over production. A 3-fold increase in IL-1ß in AAV2/5 ATF4-injected retinas (N=4), suggested that the PERK UPR arm that leads to the ATF4 mRNA increase may be responsible for activation of the IL-1ß mediated inflammatory signaling. The distribution of data values is shown in S.E.M., *P<0.05, **P<0.01, ***P<0.001 and ****P<0. 0001