Herpesvirus entry mediator (HVEM), also known as tumor necrosis factor receptor superfamily member 14 (TNFRSF14), is a human cell surface receptor of the TNF-receptor superfamily encoded by the TNFRSF14 gene. This protein was originally known as herpesvirus entry mediator A (HveA); HveB and HveC are structurally unrelated proteins of the immunoglobulin superfamily. It is also known as CD270 in the cluster of differentiation classification. Moreover, it is also referred to as ATAR (another TRAF-associated receptor). The protein encoded by this gene is a member of the TNF-receptor superfamily. The cytoplasmic region of this receptor was found to bind to several TNF receptor associated factor (TRAF) family members, which may mediate the signal transduction pathways that activate the immune response. In melanocytic cells TNFRSF14 gene expression may be regulated by MITF. TNFRSF14 has been shown to interact with TRAF2, TNFSF14 and TRAF5.