Elevated levels of TNF-α, IL-1β, IL-6 and Interferon-γ (IFN-γ) have been detected in striatum and substantia nigra of PD patients compared to healthy controls (Mogi et al., 1994a,b; Hunot et al., 1999; Sawada et al., 2006). Here, IL1B is linked to Parkinson disease.