IL6 and Parkinson disease: Pro-inflammatory cytokines, such as TNFα, IL-1β, IL-6, IL-2, and IL-10 are increased in postmortem brain (Mogi et al., 1994b), CSF (Mogi et al., 1994a), and serum (Dufek et al., 2009; Williams-Gray et al., 2016) of PD patients and may be predictive of disease progression.