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Retinal ganglion cell neuroprotection has been demonstrated in a number of paradigms of optic nerve injury using autoimmune modulation. Ben Simon et al. (535) investigated RGC survival one and two weeks after unilateral elevation of IOP (100 cmH2O for one hour) in Lewis rats. Animals were vaccinated with various amounts of Copolymer-1 (Cop-1) on the day of IOP elevation or three days later. A separate group of animals was given Cop-1 drops to the untreated eye on the day of IOP elevation. RGC survival was quantified by flat-mount counts of back-labeled RGCs at one and two weeks after IOP elevation. When compared to control animals not immunized by Cop-1, RGC survival was significantly increased in the animals receiving a single injection of Cop-1 the day of IOP elevation. RGC survival was not significantly increased when Cop-1 was given three days after IOP elevation. Interestingly, administration of Cop-1 eye drops to the contralateral eye at the time of IOP elevation led to an increase in RGC survival similar to that seen with Cop-1 injection. The authors claim that RGC loss in this experimental paradigm was due to acute IOP elevation alone. Examination of retinal vasculature was not detailed in these ketamine/xylazine anesthetized rats, so the role of ischemia cannot be ruled out. Although the authors examined only early time-points after IOP elevation, the reported increase in survival of RGCs after immediate immune modulation with Cop-1 may provide a useful therapeutic adjunct in the setting of acute IOP elevation such as that seen in narrow angle glaucoma attacks.