PRRT2 and Alzheimer disease: Given that PKC is ubiquitously expressed in immune and nonimmune cells, and that it governs diverse cellular processes including cell migration and gene expression [21], it is conceivable that 4H3MC might regulate the migration of DCs, mast cells, and keratinocytes, and also regulate cytokine production by keratinocytes, thereby activating DCs to prime naïve T cells to differentiate into Th2 cells during AD development.