TNF and glaucoma: Moreover, Barres and colleagues demonstrate in the CNS that neurotoxic astrocytes are induced by activated microglia [72] and blocking microglial activation with minocycline [14, 20] or anti-TNF [22, 23] prevents axon degeneration and death of RGCs suggesting that activated microglia are the driving force behind the axon degeneration and death of RGCs in glaucoma.