AlphaLISA Human 4-1BB / 4-1BBL Binding Kit, 500 Assay Points

The AlphaLISA™ human 4-1BB and human 4-1BBL binding assay uses anti-6xHis AlphaLISA Acceptor beads to capture the His-tagged 4-1BB and Streptavidin-coated donor beads to capture the biotinylated 4-1BBL. Donor beads and Acceptor beads come into proximity through 4-1BB binding to 4-1BBL. Excitation of the Donor beads provokes the release of singlet oxygen that triggers a cascade of energy transfer reactions in the Acceptor beads, resulting in a sharp peak of light emission at 615 nm.

Formats:

• Our 500 assay point kit allows you to run 500 wells in 96-well or 384-well format, using a 50 µL reaction volume.
• Our 5,000 assay point kit allows you to run 5,000 wells in 96-well or 384-well format, using a 50 µL reaction volume.

AlphaLISA features:

• No-wash steps, no separation steps
• Ease-of-use: few addition steps, fast assay development
• Broad range of affinities: detect strong or weak interactions, from pM to mM affinity
• Distance: measure very large protein or antibody complexes – spanning up to 200 nm or more
• High avidity: multiple binding sites on each bead enables use of nanomolar concentrations of antibodies or proteins, as well as use of low affinity binders

4-1BB is a member of the TNF superfamily. It is a type 2 transmembrane glycoprotein receptor with approximate molecular weight of 30 kDa and expressed mostly on activated T Lymphocytes. The expression is also reported on dendritic cells, B cells, follicular dendritic cells, natural killer cells, granulocytes and cells of blood vessel walls at sites of inflammation. It has many different names such as CD137 and TNFRSF9. 4-1BB binds with high affinity to the transmembrane 4-1BB Ligand/TNFSF9 which is expressed on antigen presenting cells and myeloid progenitor cells. This interaction co‑stimulates the proliferation, activation, and/or survival of the 4-1BB expressing cells. 4-1BB activation enhances CD8+ T cell and NK cell mediated anti-tumor immunity. Soluble forms of 4-1BB and 4-1BB Ligand circulate at elevated levels in the serum of rheumatoid arthritis and hematologic cancer patients, respectively.