Abstract 1656: Luminescent assay platforms accelerate therapeutic antibody development in veterinary immuno-oncology

Abstract Advances in immuno-oncology increasingly depend on translational animal models to inform mechanism of action (MoA), pharmacokinetics, and therapeutic potential. Beyond their preclinical utility for human therapies, these models are critical for developing novel biologics in veterinary oncology, particularly in canine cancers, which share key demographic, immunologic and molecular features with human disease. A major limitation in this research is the lack of robust analytical tools to characterize species-specific antibody function and receptor engagement. We developed a suite of luminescent, cell-based bioassays to quantify Fc-mediated effector mechanisms, including antibody-dependent cellular cytotoxicity (ADCC). Each assay incorporates canine Fcγ receptors and features luciferase reporters, providing sensitive, quantitative, and reproducible readouts suitable for potency and MoA evaluation. In addition, cell-based reporter bioassays were developed to measure the potencies of antibodies that modulate canine immune checkpoints (PD-1/PD-L1) or co-stimulatory receptors (CD40). Complementing these cell-based tools, an improved canine antibody binding assay offers a rapid, homogeneous alternative to ELISA and SPR methods for characterizing antibody-target interactions. The assay supports antibody development from screening to potency release testing of veterinary antibody therapeutics. Together, these luminescent assay platforms streamline veterinary immuno-oncology research, accelerating translation of therapeutic antibodies across species. Citation Format: Jun Wang, Denise Garvin, Ildiko Kasza, Jim Hartnett, Mei Cong, Jamison Grailer, . Luminescent assay platforms accelerate therapeutic antibody development in veterinary immuno-oncology [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2026; Part 1 (Regular Abstracts); 2026 Apr 17-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2026;86(7 Suppl):Abstract nr 1656.