CD4 and Parkinson disease: Brain-resident macrophages have been shown to present antigen to CD4+ T cells in Parkinson’s disease models.65,66 Depletion of microglia and brain-resident macrophages enhances phospho-tau deposition in P301S−/− models leading to premature death compared with controls.36,67 Brain-resident macrophages also change considerably with age and those changes could have impacts on VCID onset and progression.13,68 Thus, we examined the 7,913 non-microglial myeloid cells in our dataset.