• Purity

  >90%, by SDS-PAGE with silver staining

• Endotoxin Level

  <0.10 EU per 1 μg of the protein by the LAL method.  

• Activity

  Measured by its binding ability in a functional ELISA. When recombinant rat OX40 Ligand is coated at 75 ng/mL (100 μL/well), the concentration of Recombinant OX40 Fc Chimera that produces 50% optimal binding response is 1-5 ng/mL.

• Source

  Mouse myeloma cell line, NS0-derived

  Rat OX40/TNFRSF4 (Val20-Pro210) Accession # P15725	IEGRMDP	Mouse IgG2a (Glu98-Lys330)
  N-terminus		C-terminus

• Accession #

• N-terminal Sequence    
  Analysis

  Val20 & Val22

• Structure / Form

  Disulfide-linked homodimer

• Predicted Molecular Mass

  48 kDa (monomer)

• SDS-PAGE

  67-78 kDa reducing conditions

Background: OX40/TNFRSF4

OX40 (CD134; TNFRSF4) is a T cell co-stimulatory molecule of the TNF receptor superfamily that coordinates with other co-stimulators (CD28, CD40, CD30, CD27 and 4-1BB) to manage the activation of the immune response (1-3). Rat OX40 is a 50 kDa type I transmembrane glycoprotein with a 20 amino acid (aa) signal sequence, a 191 aa extracellular domain (ECD) that contains a cysteine-rich region, a 25 aa transmembrane segment, and a 36 aa cytoplasmic domain (4). The ECD of rat OX40 shares 90% and 63% sequence identity with the ECD of mouse and human OX40, respectively. OX40 is up-regulated on CD4  ⁺ and CD8  ⁺ T cells upon engagement of the TCR by antigen presenting cells along with co-stimulation by CD40-CD40 Ligand and CD28-B7 (5, 6). OX40 Ligand is primarily expressed on antigen presenting cells (5). OX40 Ligand engagement of OX40 on activated CD4  ⁺ T cells results in increased T cell survival, proliferation, and cytokine production. It also inhibits the conversion of effector T cells into immunosuppressive regulatory T cells (Tregs) and can promote the maintenance of and recall response in memory T cells (3, 7-10). OX40 is constitutively expressed on Tregs and enhances the sensitivity of Tregs to IL-2, thus promoting Treg proliferation. OX40 has also been shown to decrease the cells’ immunosuppressive activity on effector T cells (11-14). OX40-OX40 Ligand signaling is involved in allergic airway inflammation, graft-versus-host disease and autoimmune disease (6, 15, 16). Mutations in OX40 and OX40 Ligand are associated with cardiovascular disease (17, 18).

• References:

1. Hori, T. (2006) Int. J. Hematol. 83:17.

2. Latza, U. et al. (1994) Eur. J. Immunol. 24:677.

3. Salek-Ardakani, S. et al. (2003) J. Exp. Med. 198:315.

4. al-Shamkhani, A. et al. (1996) Eur. J. Immunol. 26:1695.

5. Moran, A.E. et al. (2013) Curr. Opin. Immunol. 25:230.

6. Gramaglia, I. et al. (1998) J. Immunol. 161:6510.

7. Xiao, X. et al. (2008) J. Immunol. 181:3193.

8. So, T. and M. Croft (2007) J. Immunol. 179:1427.

9. Mousavi, S.F. et al. (2008) J. Immunol. 181:5990.

10. Bansal-Pakala, P. et al. (2001) Nat. Med. 7:907.

11. Piconese, S. et al. (2010) Eur. J. Immunol. 40:2902.

12. Griseri, T. et al. (2010) J. Exp. Med. 207:699.

13. Xiao, X. et al. (2012) J. Immunol. 188:892.

14. Vu, M.D. et al. (2007) Blood 110:2501.

15. Damayanti, T. et al. (2010) Am. J. Respir. Crit. Care Med. 181:688.

16. Xiao, X. et al. (2012) Nat. Immunol. 13:981.

17. Nakano, M. et al. (2010) Cardiovasc. Res. 88:539.

18. Ishii, N. et al. (2010) Adv. Immunol. 105:63.

• Entrez Gene IDs:

  7293 (Human); 22163 (Mouse); 25572 (Rat); 102145978 (Cynomolgus Monkey)

• Alternate Names:

  ACT-135; ACT35 antigen; ACT35ATC35 antigen; CD134 antigen; CD134; Ly-70; OX40 cell surface antigen; OX40 homologue; OX40; OX40L receptor; OX40lymphoid activation antigene ACT35; TAX transcriptionally-activated glycoprotein 1 receptor; tax-transcriptionally activated glycoprotein 1 receptor; TNFRSF4; tumor necrosis factor receptor superfamily member 4; tumor necrosis factor receptor superfamily, member 4; Txgp1; TXGP1L; TXGP1LOX40 antigen