Human CD137L (4-1BB Ligand) is a type II transmembrane protein constitutively expressed by monocytes, B cells and neuroblastoma cells (1). Binding of CD137 (4-1BB) to CD137L induces monocyte activation (2).

Molecular Structure: A soluble molecule consisting of the extracellular domain of murine CD8 alpha(167aa): kpqapelrifpkkmdaelgqkvdlvcevlgsvsqgcswlfqnsssklpqptfvvymasshnkitwdeklnssklfsamrdtnnkyvltlnkfskenegyyfcsvisnsvmyfssvvpvlqkvnstttkpvlrtpspvhptgtsqpqrpedcrprgsvkgtgldfacd

Linking amino acids: gt

Fused to the extracellular domain of human CD137L (184aa): regpelspddpaglldlrqgmfaqlvaqnvllidgplswysdpglagvsltgglsykedtkelvvakagvyyvffqlelrrvvagegsgsvslalhlqplrsaagaaalaltvdlppassearnsafgfqgrllhlsagqrlgvhlhteararhawqltqgatvlglfrvtpeipaglpsprse

Predicted non glycosylated monomeric molecular weight: 38.2 kd.

Transfectant Cell Line: CHO

Functional Application: Human CD137L-muCD8 binds to CD137 in FACS (3) and EIA(4). It blocks binding of anti-CD137 monoclonal antibody (clone 4B4-1) to CD137 expressing cells in FACS. Immobilzed CD137L can induce cytokine expression (IL-4, IL-10, IL-13) by CD137 expressing T cells (5).

References:

1. M.R. Alderson, et al, (1994) Eur J Immunol 24: 2219-2227.

2. J. Langstein, et al, (1998) J Immunol 160: 2488-2494.

3. W.Lin, S.E. Strome, et al. (2008) Blood 112: 699-707. PMID 18519814

4. M Cho, J Myoung (Dec 2015) J General Virology 96(12): 3635-3645. PMID 26467721

5. Alfaro C, Melero I, et al. (2015) OncoImmunology 4(12): e1054597. doi: 10.1080/2162402X.2015.1054597.