PILRA and Parkinson disease: PILRA is a cell surface inhibitory receptor expressed on innate immune cells, including microglia.78,79 In our analysis, PILRA was associated with caudate nucleus atrophy, which has been previously observed in other neurodegenerative diseases, including frontotemporal dementia, PD and Huntington’s disease.80-82 This finding could indicate that HSV-1 participates in the pathogenesis of AD by affecting caudate nucleus.