|CD275||ICOSLG (inducible T-cell co-stimulator ligand), ICOS-L, B7-H2 (B7-homologue 2), B7RP-1 (B7-related protein), LICOS (ligand for ICOS)|
|Molecule Type||Antigen Expression||Molecular Weight|
Min / Max
|Non-lineage Restricted Molecule|
Type 1 glycoprotein
|40 / 40|
60 / 60
|CD275 is expressed on endothelial cells, macrophages, dendritic cells, T and B cells and activated monocytes. Isoform 1 is widely expressed in brain, kidney, liver, lung, pancreas, placenta, skeletal muscle, bone marrow, colon, ovary, prostate, testis, lymph nodes, leukocytes, spleen, thymus and tonsil. Isoform 2 is detected only in lymph nodes, leukocytes and spleen. Constitutive expression is further enhanced by treatment with TNF-α in peripheral blood B cells and monocytes, while it is decreased in dendritic cells.|
|MOLECULAR FAMILY NAME: Belongs to the immunoglobulin gene family.|
CD275 is a single-pass type-1 302 aa glycoprotein. It contains a transmembrane domain which contains an Ig-like C2-type domain, an 1 Ig-like V-type domain and 5 conserved cysteine residues, a transmembrane domain and a cytoplasmic domain. CD275 is a member of B7 family of co-stimulatory molecules.
Alternative splicing yields 2 different isoforms. The isoforms differ at the C-terminal end of the cytoplasmic domain.
POST-TRANSLATIONAL MODIFICATION: No information.
|LIGANDS AND MOLECULE ASSOCIATED WITH CD275|
CD275 is a T cell co-stimulator ligand for the T cell specific cell surface receptor CD278 (ICOS).
|CD275 binds only CD278 and does not bind the other ICOS homologues CD28 or CD152 (CTLA-4). Engagement of CD278 on activated T cells by CD275 bearing cells increases cytokine secretion, acts as a costimulatory signal for T cell proliferation and also induces B cell proliferation and differentiation into plasma cells. |
It could play a role in mediating local tissue responses to inflammatory conditions, as well as in modulating the secondary immune response by co-stimulating memory T cell function. This co-stimulation of anti-CD3-stimulated T cells is reported to promote proliferation and cytokine production.
BIOCHEMICAL ACTIVITY: No information.
DISEASE RELEVANCE AND FUNCTION OF CD275 IN INTACT ANIMAL
CD275 knockout mice have not been described. Transgenic mice over-expressed with soluble CD275 fusion protein showed lymphoid hyerplasia. The CD278/CD275 interaction appears to be important in the cognate interaction between T cells and antigen presenting cells and play a role pathological situations such as graft rejection and allergic airway inflammation and the pathway is a target for therapeutic intervention. Most studies have focused on signal transduction through CD278 to the T-cell, but by analogy with the other B7 family members, it is possible that signals are transmitted through CD275 to the antigen presenting cell, endothelial or B cell.
PROTEINS AND DNA ELEMENTS WHICH REGULATE TRANSCRIPTION OF CD275: No information.
SUBSTRATES: No information.
ENZYMES WHICH MODIFY CD275: No information.
For further information see Yoshinaga, S. K. et al (2000) Int. Immunol. 12: 1439-1447.
Database accession numbers
Revised June 25, 2008