Toll-like receptor agonists and invariant natural killer T-cells enhance antibody-dependent cell-mediated cytotoxicity (ADCC)

huHMFG-1 (AS1402) is a humanised IgG1 against MUC1, which exerts tumour cell killing through antibody-dependent cellular cytotoxicity (ADCC) mediated by natural killer (NK) cells. Here, we explored the capacity of invariant NKT (iNKT) cells, which are known to activate NK cells, and toll-like receptor (TLR) ligands which activate both iNKT and NK cells, to enhance huHMFG-1-ADCC. Addition of iNKT cells, as well as TLR2/6, 7, 8 and 9 agonists to PBMC improved the efficacy of huHMFG-1. These results suggest that transfer of ex vivo expanded iNKT cells or TLR agonist treatment may improve the efficacy of NK cell-mediated antibody-based tumour immunotherapies.