CD27 (also known as TNFRSF7) is a type I glycoprotein expressed on some B cells and the majority of T cells,and is a member of the tumor necrosis factor (TNF) receptor family. CD27 is required for generation and long-term maintenance of T cell immunity . It is a receptor for CD70 (Cd27L). Ligation of CD27 by CD70 induces strong ubiquitination of TRAF and the activation of both canonical and non-canonical NF-kappaB pathways,as well as the JNK pathway . CD27 may also play a role in apoptosis through association with SIVA1.