Indeed, microglia and astrocyte activation, in addition to lymphocyte infiltration and cytokine production (IL-1β, IL-2, IL-4, IL-6, IL-10, TNF-α, and IFN-γ), have been documented in PD 20, 75-77 Some researchers interpret the inflammation as a result of neural death and the appearance of cell debris that should be cleared from the brain in PD patients. The gene discussed is IL4; the disease is Parkinson disease.