TNF and Parkinson disease: In parallel with this, high expression levels of chemokines, interleukins, interferons, and tumor necrosis factor-α (TNF-α) have been discovered in the striatum and substantia nigra of PD post-mortem brain samples and CSF of AD patients (Hirsch and Hunot, 2009; Llano et al., 2012; Gelders et al., 2018).