Human 4-1BB Ligand (4-1BBL, CD137L) is a 32kD type II transmembrane protein that belongs to TNF superfamily (TNFSF) of molecules.1-4 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.5 The extracellular domain (ECD) of 4-1BBL has a jelly-roll, β-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.2, 3, 6 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.4 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-α) by monocytes.7, 8 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-γ in CD4+ cells, and IFN-γ in CD8+ cells.9, 10
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)
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.
仕様
Size：100ug
Source Antigen：Recombinant, human from E. coli
Grade：Molecular Biology Grade
Purity：≥ 95%, as determined by SDS-PAGE and visualized by silver stain.
Form：Supplied as a liquid in 20mM Tris-HCl, pH 8, 100mM sodium chloride, 20% glycerol.
