CD27 Gene: Function, Expression, Mutations & Associated Diseases

CD27 is a member of the tumor necrosis factor receptor (TNFR) superfamily. It is expressed on the surface of lymphocytes, particularly T cells, B cells, and natural killer (NK) cells. CD27 binds to its ligand CD70, providing a co-stimulatory signal essential for T-cell expansion, B-cell differentiation, and plasma cell survival. CD27 signaling also regulates germinal center responses and memory B-cell formation. Loss-of-function mutations in CD27 cause a primary immunodeficiency characterized by severe Epstein-Barr virus (EBV) infection and lymphoproliferation. Somatic mutations and altered expression of CD27 are observed in various lymphomas and leukemias.

Tissue Expression

Cell Line Expression

Hotspot Mutations

Mutation functional classification

• CD27/CD70 signaling in lymphocytes (Reactome: R-HSA-5673001)

• TNF receptor superfamily signaling (KEGG: hsa04060)

• NF-kappa B signaling pathway (KEGG: hsa04064)

CD27 is a type I transmembrane glycoprotein of 260 amino acids (UniProt P26842). It contains two cysteine-rich domains in the extracellular region characteristic of the TNFR superfamily. The intracellular domain contains a TRAF-binding motif that recruits TRAF2 and TRAF5, leading to activation of NF-κB and MAPK pathways. CD27 is expressed as a disulfide-linked homodimer on the cell surface. Proteolytic cleavage by ADAM17 releases a soluble form (sCD27) that can be detected in serum and is elevated in inflammatory conditions and lymphomas.