TNF and glaucoma: Following optic nerve damage and in glaucoma, one proposed mechanism for RGC death is that reactive microglia express proteins that include tumor necrosis factor-⍺ (TNF⍺), interleukin 1⍺ (IL-1⍺), and the complement protein C1q, which together polarize astrocytes to a pro-inflammatory “A1” state [56,57,58,59].