Lumit: a novel bioluminescent, homogenous immunoassay platform for analyte detection

• Published in: The Journal of immunology (1950) 2022-05, Vol.208 (1_Supplement), p.173-173.12
• Main Authors: Bach, Maggie L, O’Brien, Martha A., Nath, Nidhi, Zegzouti, Hicham, Lazar, Dan, Cali, James
• Format: Article
• Language: English
• ISSN: 0022-1767; 1550-6606
• DOI: 10.4049/jimmunol.208.Supp.173.12

The detection of a specific analyte in a complex mixture by an immunoassay is a common procedure in many bioanalytical workflows. Immunoassays rely on the interaction between labeled antibodies and the analyte of interest. We have developed Lumit, a novel bioluminescent labeling approach allowing no-wash immunoassays amenable for high-throughput applications. Lumit immunoassay technology is based on an adaptation of NanoBiT® luciferase, a structural complementation system that consists of the Large BiT (LgBiT; 18 kDa) subunit and a small, complementary peptide, Small BiT (SmBiT; 11 amino acids), that has low affinity for LgBiT. Antibodies labeled with LgBiT or SmBiT subunits are brought into proximity due to binding to a target analyte. This facilitated complementation reconstitutes an active luciferase and generates light proportional to the amount of analyte present. This detection chemistry has several advantages over traditional ELISA workflows, including a no-transfer and no-wash protocol suitable for automation, fast detection time (30 – 90 minutes), and a broad dynamic range mitigating the need for sample dilutions. Here, we present a variety of applications of Lumit technology to detect analytes in immunology research. Examples include detection of cytokines from activated cultured immune cells using labeled primary antibodies, the detection of antibody-Fc receptor binding, the detection of protein phosphorylation using labeled secondary antibodies, and detection of the PD1: PDL1 interaction using labeled anti-tag antibodies.