Although a deeper comprehension of cell-specific signaling pathways awaits to be defined, given that TSLP has been found capable of directly acting on CD4+ T cells and of promoting proliferation and T-helper 2 differentiation of naïve CD4+ T cells through the induction of interleukin-4 [20], it seems reasonable to hypothesize that the overexpression of mRNA TSLP in the skin of CV patients and the consequent cytokine milieu play an important role in the inflammatory responses that characterize this peculiar type of HCV-induced vasculitis. This evidence concerns the gene IL4 and vasculitis.