IL2 and supranuclear palsy, progressive, 1: Recent studies have also found that brain neuroinflammation is associated with the severity of symptoms in PSP.57,58 Such neuroinflammation co-localizes anatomically with tau pathology in the brain59 and patients with PSP also show increased levels of IL-2 and shifts in peripheral T-cell populations.60 Notably, increased leucocytes in this study correlated with lowered CSF Aβ42 levels.