CD137 is a member of the tumor necrosis factor (
TNF
Tumor necrosis factor (TNF, cachexin, or cachectin; formerly known as tumor necrosis factor alpha or TNF-α) is an adipokine and a cytokine. TNF is a member of the TNF superfamily, which consists of various transmembrane proteins with a homolog ...
) receptor family. Its alternative names are ''tumor necrosis factor receptor superfamily member 9'' (TNFRSF9), 4-1BB and ''induced by lymphocyte activation'' (ILA). It is of interest to immunologists as a co-stimulatory
immune checkpoint
Immune checkpoints are regulators of the immune system. These pathways are crucial for self-tolerance, which prevents the immune system from attacking cells indiscriminately. However, some cancers can protect themselves from attack by stimula ...
molecule.
Expression
CD137 is expressed by activated
T cells
A T cell is a type of lymphocyte. T cells are one of the important white blood cells of the immune system and play a central role in the adaptive immune response. T cells can be distinguished from other lymphocytes by the presence of a T-cell re ...
of both the
CD4+
In molecular biology, CD4 (cluster of differentiation 4) is a glycoprotein that serves as a co-receptor for the T-cell receptor (TCR). CD4 is found on the surface of immune cells such as T helper cells, monocytes, macrophages, and dendritic ...
and
CD8+
A cytotoxic T cell (also known as TC, cytotoxic T lymphocyte, CTL, T-killer cell, cytolytic T cell, CD8+ T-cell or killer T cell) is a T lymphocyte (a type of white blood cell) that kills cancer cells, cells that are infected by intracellular pa ...
lineages. Although it is thought to function mainly in co-stimulating those cell types to support their activation by antigen presenting cells expressing its ligand (CD137L), CD137 is also expressed on dendritic cells, B cells, NK cells, neutrophils and macrophages.
Specific effects on cells
The best characterized activity of CD137 is its costimulatory activity for activated T cells. Crosslinking of CD137 enhances T cell proliferation, IL-2 secretion, survival and cytolytic activity. Further, it can enhance immune activity to eliminate tumors in mice.
Interactions
CD137 has been shown to
interact
Advocates for Informed Choice, dba interACT or interACT Advocates for Intersex Youth, is a 501(c)(3) nonprofit organization using innovative strategies to advocate for the legal and human rights of children with intersex traits. The organizati ...
with
TRAF2
TNF receptor-associated factor 2 is a protein that in humans is encoded by the ''TRAF2'' gene.
Function
The protein encoded by this gene is a member of the TNF receptor associated factor (TRAF) protein family. TRAF proteins associate with, an ...
.
As a drug target
Utomilumab
Utomilumab (PF-05082566) targets this receptor to stimulate a more intense immune system attack on cancers.
[Pfizer cancer drug shows promise in combo with Merck's Keytruda. May 2016]
/ref> It is a fully human IgG2 monoclonal antibody. It is in early clinical trials.[ 5 clinical trials are active.PF-05082566 trials]
/ref>
See also
* 4-1BB ligand
Tumor necrosis factor ligand superfamily member 9 also known as 4-1BB ligand or 4-1BBL or CD137L is a protein that in humans is encoded by the TNFSF9 gene.
4-1BBL is a type 2 transmembrane glycoprotein receptor that is found on APCs (antigen pre ...
* Urelumab
References
External links
*
Further reading
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
{{DEFAULTSORT:Cd137
Oncology
Immunology