TLR3 and viral infectious disease: Poly(I:C) mimics viral infection by activating Toll-like receptor 3 (TLR3) and increasing the expression of immune cytokines, including IL-6 and members of the poly ADP-ribose polymerase (PARP) family [10], leading to immune activation and apoptosis in many cell types, including epithelial cells of the genital tract [5].