TLR9 and infection: <h4>Introduction</h4>The objective of this study was to investigate the effect of acyclovir (ACV) on the TLR9 signaling pathway after human immortalized epidermal (HaCaT) cell infection with herpes simplex virus type 2 (HSV-2).<h4>Methods</h4>In this study, an <i>in vitro</i> cell model of HSV-2 infection was successfully constructed by infecting HaCaT with HSV-2 virus.