This kit is designed for the detection of binding between FCGR1 (CD64) and human IgG Fc fragment using a homogeneous AlphaLISA assay (no wash steps). This assay can facilitate the design and development of antibody therapeutics 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

The Fc-Gamma Receptors (FCGRs) are members of immunoglobulin superfamily and play a critical role in the function of therapeutic antibodies. FCGRs are divided into three classes Fc-Gamma Receptor 1 (CD64), FCGR1; Fc-Gamma Receptor 2 (CD32), FCGR2 and Fc-Gamma receptor 3 (CD16), FCGR3.

FCGR1 is a high affinity Fc-gamma receptor, also known as FCGR1A and CD64. FCGR1 is a transmembrane protein with three extracellular Ig-like domains, and it delivers an activating signal via the associated Fc R gamma accessory chain. FCGR1 permits the triggering of effector responses at low IgG concentrations typical of early immune responses.

The AlphaLISA detection of FCGR1 and IgG Fc fragment binding uses IgG Fc AlphaLISA Acceptor beads to capture the human FCGR1 and Streptavidin-coated Donor beads to capture the biotinylated human FCGR1. Donor beads and Acceptor beads come into proximity through IgG Fc fragment binding to FCGR1. 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.