B7-H4 Proteins

Protein Information

B7-H4 (B7x, VTCN1) a costimulatory protein which is reported to function as a negative regulator of T-cell mediated immunity. Although B7-H4 binds an unknown receptor, it is thought to deliver an inhibitory signal to T-cells preventing their proliferation, cell cycle progression and interleukin-2 production. B7-H4 deficient mice are only minimally affected; suggesting B7-H4 is important in the fine tuning of the T-cell mediated immune response. B7-H4 is expressed on activated T-cells, B-cells, monocytes and dendritic cells. Aberrant expression has been associated with cancers of the lung, breast and ovary in humans. B7-H4 is expressed primarily on the membrane of lymphoid cells, and as an immunoinhibitory protein that interacts with receptors on the surface of T lymphocytes, it is involved in mediating cellular and humoral immune responses. Overexpression of B7-H4 is associated with certain malignancies, including ovarian and breast cancer, which may be a mechanism by which tumor cells suppress T cell immunity and facilitate tumor progression. Further, VTCN1 may be a useful biomarker for the early detection of ovarian cancer and Renal Cell Carcinoma (RCC).

Synonyms

B7 family member, H4; B7 homolog 4; B7 superfamily member 1; B7h.5; B7h4; B7-H4; B7S1; B7x; BC032925; EMBL:AAH95842.1}; FLJ22418; Immune costimulatory protein B7-H4; PRO1291; Protein B7S1; RGD1311204; RP11-229A19.4; T cell costimulatory molecule B7x; T-cell costimulatory molecule B7x; UNQ659/PRO1291; VCTN1; V-set domain containing T cell activation inhibitor 1; V-set domain containing T-cell activation inhibitor 1; V-set domain-containing T-cell activation inhibitor 1; vtcn1; vtcn1 {ECO:0000312