IL4 and Parkinson disease: Critical findings of this study include the genotype-dependent effect of HPgV infection on IL-4 signaling and the YWHAB (14-3-3 β) gene network—specifically, increasing HPgV titer results in opposing regulatory effects in the detection of IL-4 as an upstream regulator and differential expression of YWHAB and its interacting partners between PD-WT and PD-LRRK2 genotypes.