Abstract #3899

Multi-Modal Imaging to Evaluate the Effects of Novel TLR Agonist Adjuvants in Vaccine-Mediated Tumor Immunity

Deepak K. Kadayakkara¹, Hyam I. Levitsky¹, Jeff W.M. Bulte²,³

¹Department of Oncology, Johns Hopkins School of Medicine, Baltimore, MD, United States; ²Cellular Imaging Section, Institute for Cell Engineering,, Johns Hopkins University, Baltimore, MD, United States; ³MRI research division, Johns Hopkins School of Medicine, Baltimore, MD, United States

We evaluated the effects of novel adjuvants in cancer vaccines using non-invasive imaging. Magnetovaccination and MRI were used to evaluate dendritic cell-mediated antigen capture and delivery to regional lymph nodes. The ensuing effector immune response mediated by T cells was studied by antigen-specific transgenic T cells and bioluminescence imaging. We show that, unexpectedly, adjuvants reduced antigen delivery to lymph nodes; however they induced a more effective tumor therapeutic response suggesting an alternate and hitherto unreported pathway for T cell expansion and accumulation.