From Wikipedia, the free encyclopedia
Jump to navigation Jump to search
Protein TNFRSF4 PDB 2hev.png
Available structures
PDBOrtholog search: PDBe RCSB
AliasesTNFRSF4, ACT35, CD134, IMD16, OX40, TXGP1L, tumor necrosis factor receptor superfamily member 4, TNF receptor superfamily member 4
External IDsOMIM: 600315 MGI: 104512 HomoloGene: 2496 GeneCards: TNFRSF4
RefSeq (mRNA)



RefSeq (protein)



Location (UCSC)Chr 1: 1.21 – 1.21 Mbn/a
PubMed search[2][3]
View/Edit HumanView/Edit Mouse

Tumor necrosis factor receptor superfamily, member 4 (TNFRSF4), also known as CD134 and OX40 receptor, is a member of the TNFR-superfamily of receptors which is not constitutively expressed on resting naïve T cells, unlike CD28. OX40 is a secondary co-stimulatory immune checkpoint molecule, expressed after 24 to 72 hours following activation; its ligand, OX40L, is also not expressed on resting antigen presenting cells, but is following their activation. Expression of OX40 is dependent on full activation of the T cell; without CD28, expression of OX40 is delayed and of fourfold lower levels.


OX40 has no effect on the proliferative abilities of CD4+ cells for the first three days, however after this time proliferation begins to slow and cells die at a greater rate, due to an inability to maintain a high level of PKB activity and expression of Bcl-2, Bcl-XL and survivin. OX40L binds to OX40 receptors on T-cells, preventing them from dying and subsequently increasing cytokine production. OX40 has a critical role in the maintenance of an immune response beyond the first few days and onwards to a memory response due to its ability to enhance survival. OX40 also plays a crucial role in both Th1 and Th2 mediated reactions in vivo.

OX40 binds TRAF2, 3 and 5 as well as PI3K by an unknown mechanism. TRAF2 is required for survival via NF-κB and memory cell generation whereas TRAF5 seems to have a more negative or modulatory role, as knockouts have higher levels of cytokines and are more susceptible to Th2-mediated inflammation. TRAF3 may play a critical role in OX40-mediated signal transduction. CTLA-4 is down-regulated following OX40 engagement in vivo and the OX40-specific TRAF3 DN defect was partially overcome by CTLA-4 blockade in vivo. TRAF3 may be linked to OX40-mediated memory T cell expansion and survival, and point to the down-regulation of CTLA-4 as a possible control element to enhance early T cell expansion through OX40 signaling.

Clinical significance[edit]

OX40 has been implicated in the pathologic cytokine storm associated with certain viral infections, including the H5N1 bird flu.[citation needed]

As a drug or drug target[edit]

An artificially created biologic fusion protein, OX40-immunoglobulin (OX40-Ig), prevents OX40 from reaching the T-cell receptors, thus reducing the T-cell response. Experiments in mice have demonstrated that OX40-Ig can reduce the symptoms associated with the cytokine storm (an immune overreaction) while allowing the immune system to fight off the virus successfully.[citation needed]

An anti-OX40 antibody GSK3174998 has started clinical trials as a cancer treatment.[4] Research in mice has included the combination of an agonistic OX40 antibody (clone OX86) injected directly into a tumor in combination with an unmethylated CpG oligonucleotide, which as a TLR9 ligand activates expression of OX40 so that it can be affected.[5]


CD134 has been shown to interact with TRAF5[6] and TRAF2.[7]


  1. ^ a b c GRCh38: Ensembl release 89: ENSG00000186827 - Ensembl, May 2017
  2. ^ "Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
  3. ^ "Mouse PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
  4. ^ "GSK and Merck to study immunotherapy combination as potential cancer treatment. Nov 2015". Archived from the original on 4 February 2017. Retrieved 6 April 2016.
  5. ^ Sagiv-Barfi I, Czerwinski DK, Levy S, Alam IS, Mayer AT, Gambhir SS, Levy R (2018). "Eradication of spontaneous malignancy by local immunotherapy". Science Translational Medicine. 10 (426): eaan4488. doi:10.1126/scitranslmed.aan4488. ISSN 1946-6234. PMC 5997264. PMID 29386357.
  6. ^ Kawamata S, Hori T, Imura A, Takaori-Kondo A, Uchiyama T (March 1998). "Activation of OX40 signal transduction pathways leads to tumor necrosis factor receptor-associated factor (TRAF) 2- and TRAF5-mediated NF-kappaB activation". The Journal of Biological Chemistry. 273 (10): 5808–14. doi:10.1074/jbc.273.10.5808. PMID 9488716.
  7. ^ Arch RH, Thompson CB (January 1998). "4-1BB and Ox40 are members of a tumor necrosis factor (TNF)-nerve growth factor receptor subfamily that bind TNF receptor-associated factors and activate nuclear factor kappaB". Molecular and Cellular Biology. 18 (1): 558–65. doi:10.1128/MCB.18.1.558. PMC 121523. PMID 9418902.

External links[edit]

Further reading[edit]