This kit is designed for the detection of binding activity between PD-1 and PD-L1 using a homogeneous AlphaLISA assay (no wash steps). This assay can facilitate the design and development of therapetics by using competitive binding.

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

AlphaLISA technology allows the detection of molecules of interest in buffer, cell culture media, serum and plasma in a highly sensitive, quantitative, reproducible and user-friendly mode. In an AlphaLISA assay, a biotinylated PD-1 binds to the Streptavidin-coated Alpha Donor beads, while His tagged PD-L1 is captured by Anti-His AlphaLISA Acceptor beads. When PD-L1 binding to PD-1 happens, Donor beads and Acceptor beads come into close proximity. The excitation of the Donor beads provokes the release of singlet oxygen molecules that triggers a cascade of energy transfer in the Acceptor beads, resulting in a sharp peak of light emission at 615 nm.

Programmed death ligand 1 (PD-L1), also known as "cluster of differentiation 274" (CD274) or B7 homolog1 (B7-H1) belongs to the growing B7 family of immune proteins and is expressed in tumor cells. PD-L1 binds to its receptor, PD-1, found on activated T cells, B cells, and myeloid cells, to modulate activation or inhibition. By binding to PD-1, PD-L1 may inhibit ongoing T-cell responses by inducing apoptosis and arresting cell-cycle progression and thus contribute to cancer growth. Monoclonal antibodies targeting PD-1 and PD-L1 are being developed as a means to boost the immune system for the treatment of non-small-cell lung cancer, melanoma, bladder, renal, and triple-negative breast cancers.