Fig 1: Parkinson’s patient monocytes are polarized towards a CD14+ pro-inflammatory phenotype with functional polarization towards monocytic-myeloid derived suppressor cells (M-MDSCs).Monocytes gated by scatter (A) were first analyzed for expression of CD14 and CD16 (B). Analysis confirms significant polarization of Parkinson’s patient monocytes towards the classical CD14+ monocyte phenotype (C); two-tailed t-test, p < 0.05. D, E Further immunophenotyping of Parkinson’s patient monocytes revealed a significant increase in the percentage of M-MDSCs characterized by expression of CD14 and absence of HLA-DR (E–G), relative to healthy controls. No change was found in granulocytic MDSCs (G- MDSCs) (F, G) characterized by expression of CD15 and CD11b. H M-MDSCs express both DAT and TH. Routine metrics such as age distribution, sex distribution, disease duration, treatment, LED score and motor scores, along with statistical analysis are included in Supplementary Tables 1 and 2. All data shown are ±SEM.