title: Characterization of bispecific T-cell Engager (BiTE) antibodies with a high-capacity T-cell dependent cellular cytotoxicity (TDCC) assay.
abstract: The Bispecific T-cell Engager (BiTE) antibody modality is a clinically validated immunotherapeutic approach for targeting tumors. Using T-cell dependent cellular cytotoxicity (TDCC) assays, we measure the percentage of specific cytotoxicity induced when a BiTE molecule engages T-cells, redirects T-cell mediated cytolysis, and ultimately kills target cells. We establish a novel luminescence-based TDCC assay quantified by measuring cell viability via constitutive expression of luciferase. The luciferase-based TDCC assay performance is valid and comparable to an adenosine triphosphate (ATP)-based detection method. We demonstrate that the luciferase-based TDCC assay is an efficient homogeneous assay format that is amenable to both suspension and adherent target cells. The luciferase-based TDCC assay eliminates the need for plate-washing protocols, allowing for higher-throughput screening of BiTE antibodies and better data quality. Assay capacity is also improved by performing serial dilutions of BiTE antibodies in 384-well format with an automated liquid handler. We describe here a robust, homogeneous TDCC assay platform with capacity for in vitro assessment of BiTE antibody potency and efficacy using multiple tumor cell lines and T-cell donors.
authors.affiliation: Therapeutic Discovery, Amgen Inc., Thousand Oaks, CA, USA aaronn@amgen.com.
authors.forename: Aaron A
authors.initials: AA
authors.lastname: Nazarian
authors.affiliation: Oncology Research, Amgen Inc., Thousand Oaks, CA, USA.
authors.forename: Ivonne L
authors.initials: IL
authors.lastname: Archibeque
authors.affiliation: Therapeutic Discovery, Amgen Inc., Thousand Oaks, CA, USA.
authors.forename: Yen H
authors.initials: YH
authors.lastname: Nguyen
authors.affiliation: Therapeutic Discovery, Amgen Inc., Thousand Oaks, CA, USA.
authors.forename: Paul
authors.initials: P
authors.lastname: Wang
authors.affiliation: Oncology Research, Amgen Inc., Thousand Oaks, CA, USA.
authors.forename: Angus M
authors.initials: AM
authors.lastname: Sinclair
authors.affiliation: Therapeutic Discovery, Amgen Inc., Thousand Oaks, CA, USA.
authors.forename: David A
authors.initials: DA
authors.lastname: Powers
mesh_terms: D003602:Cytotoxicity, Immunologic; D006801:Humans; D013601:T-Lymphocytes / Q000166:cytology / Q000276:immunology*
keywords: Bispecific T-cell Engager (BiTE®); T-cell dependent cellular cytotoxicity (TDCC); cell viability; cell-based assay; luciferase