Intended Use
For In Vitro Diagnostic Use
Summary and Explanation
CD137, or tumor necrosis factor receptor superfamily member 9 (TNFRSF9), also known as 4-1BB, is encoded by the TNFRSF9 gene on chromosome 1p36.23. CD137/TNFRSF9 is expressed on the surface of certain immune cells, such as Follicular Dendritic Cells, Monocytes, Mast Cells and Granulocytes. CD137/TNFRSF9 is barely detected on resting T cells or T-cell lines, and expression of CD137 is therefore activation dependent. It is found on activated CD4+, CD8+ or Natural Killer Cells. Activation of CD137 by its ligand, CD137L, upregulates survival genes, enhances cell division, induces cytokine production, and prevents activation-induced cell death in T cells.
One study demonstrated CD137 antibody positive IHC staining in a majority of Classical Hodgkin Lymphoma (CHL) tissues, indicating its usefulness as a diagnostic biomarker for CHL. CD137/TNFRSF9 was also found to be a highly specific immunohistochemical marker of Neoplastic Follicular Dendritic Cells. Another study investigated CD137/TNFRSF9 via IHC in malignant tumor cells and found that there was an enhanced expression of CD137/TNFRSF9 in blood vessel cells of malignant tumors compared to blood vessel cells in benign tumors or inflammatory tissues. Further studies indicate the value of CD137 antibody as a prognostic marker in Diffuse Large B-cell Lymphomas, tumor cell differentiation in Gastric Cancer as well as the correlation between CD137/TNFRSF9 expression and bone metastasis of Breast Cancer. CD137/TNFRSF9 is considerably up-regulated in human Gliomas when compared with normal brain tissue. In addition, data provides evidence for an immune cell-independent de novo expression pattern of CD137/TNFRSF9 in mainly non-neoplastic reactive astrocytes and excludes classic immunological cell types, namely lymphocytes and microglia as the source of CD37/TNFRSF9. Moreover, TNFRSF9 is predominantly expressed in a perivascular and peritumoural distribution with significantly higher expression in IDH-1 mutant gliomas.
Synonyms: cd137, anti-cd137, tnfrsf9, anti-tnfrsf9, tumor necrosis factor receptor superfamily member 9
