Interestingly, most of the proteins (CLECL1, CLEC16A, MS4A4E, and INPP5D) affecting the peripheral immune response are heavily expressed in dendritic cells, which play a major role in the immuno-inflammatory processes leading to neuroinflammation and neurodegeneration in PD (Bossù et al., 2015; Troncoso-Escudero et al., 2018). Here, MS4A4E is linked to Parkinson disease.