Development of no-wash, rapid Fcγ Receptor Binding Immunoassays using NanoBiT® Technology

Abstract

Abstract Antibody driven therapies including monoclonal antibodies (mAbs), intravenous IgG (IVIG), subcutaneous IgG (SCIG), and vaccines have made a significant impact in the treatment of many diseases including multiple cancers and autoimmune, metabolic, viral, and infectious diseases. A key mechanism of action (MOA) that makes antibody-based therapies so effective is the ability of the Fc domain of the antibody to recruit immune effector cells through their interaction with a variety of Fc receptors (FcγR). However, assessing the combined impact of interaction of the Fc domain of various antibody isotypes with diverse FcγRs (Fc/FcγR interaction) on the efficacy of the drug is challenging, primarily due to the lack of simple to use and reproducible Fc/FcγR binding assays. Furthermore, existing technologies like SPR can introduce artifacts based on assay format, sensor chip characteristics, and immobilization methods. To meet the need for reliable, simple to use assays, we have developed a suite of bioluminescent biochemical assays for the following receptors: Lumit™ FcγRI Binding ImmunoassayLumit™ FcγRIIA (H131) Binding ImmunoassayLumit™ FcγRIIA (R131) Binding ImmunoassayLumit™ FcγRIIIA (V158) Binding ImmunoassayLumit™ FcγRIIIA (F158) Binding Immunoassay These assays are homogeneous, meaning no immobilization or washing steps are required. In addition, they are rapid, easy to use in a 96-well format, and require a simple luminometer. These assays can enable better understanding of antibody MOA and hence better therapies.