4-1 BB Ligand (Tumor necrosis factor ligand superfamily member 9, TNFSF9, CD137L), human recombinant

Human 4-1BB Ligand (4-1BBL, CD137L) is a 32kD type II transmembrane protein that belongs to TNF superfamily (TNFSF) of molecules. The human 4-1BBL cDNA encodes a 254 amino acid (aa) protein that contains a 25aa N-terminal cytoplasmic domain, a 23aa transmembrane segment, and a 206aa C-terminal extracellular region. The extracellular domain (ECD) of 4-1BBL has a jelly-roll, beta-sandwich tertiary structure that is similar to other TNFSF members. There is only one cysteine in the human ECD, and no potential N-linked glycosylation sites. The potential exists, however, for O-linked glycosylation. The human 4-1BBL ECD shares 32% and 35% aa identity with mouse and rat ECD, respectively. In the cytoplasmic domain, human 4-1BBL is 55aa shorter than the equivalent region in rodents. 4-1BBL is expressed by activated B cells, macrophages, dendritic cells, activated Tcells, neurons and astrocytes. A 26kD soluble form of 4-1BBL is known to occur in human. Although it is presumably generated by MMP activity, its amino acid size is currently unreported. The soluble form is bioactive. Human 4-1BBL signals through both CD137/4-1BB and itself. Its cytoplasmic tail participates in reverse signaling that induces apoptosis in T cells and cytokine secretion (IL-6, TNF-alpha) by monocytes. 4-1BBL binding to CD137/4-1BB produces a number of effects. Its seems to play a key role in the T cell recall response. It maintains T cell numbers at the end of a primary response, and induces CD4+ and CD8+ T cells to proliferate and secrete cytokines such as IL-2 and IFN-gamma in CD4+ cells, and IFN-gamma in CD8+ cells. Source: Recombinant human 4-1BB ligand, fused to His-tag at N-terminus, was expressed in E. coli and purified by using conventional chromatography. Molecular Weight: 23.8kD (222aa) , Concentration: ~1mg/ml (determined by Bradford assay,15% SDS-PAGE (3ug), Sequence: MRGSHHHHHH GMASMTGGQQ MGRDLYDDDD KDRWGSHMRE GPELSPDDPA GLLDLRQGMF AQLVAQNVLL IDGPLSWYSD PGLAGVSLTG, GLSYKEDTKE LVVAKAGVYY VFFQLELRRV VAGEGSGSVS LALHLQPLRS AAGAAALALT VDLPPASSEA RNSAFGFQGR LLHLSAGQRL, GVHLHTEARA RHAWQLTQGA TVLGLFRVTP EIPAGLPSPR SE, Storage and Stability: Can be stored at +4°C short term (1-2 weeks). For long term storage, aliquot and store at -20°C or -70°C. Avoid repeated freezing and thawing cycles.