TLR2 and Parkinson disease: In the context of neurodegenerative diseases, Doorn et al. (2014) took advantage of immunohistochemical analyses to examine the expression of TLR2, a known receptor involved in the activation of microglia following its interaction with alpha-synuclein in the substantia nigra and hippocampus of patients with PD and incidental Lewy Body Disease (iLBD), a prodromal state of PD.