Abstract #0170

Biphasic Clearance of Depot Vaccine Antigen & Substrate Visualized Using SPIO MRI

Kim Brewer¹,², Kerry Lake³, Nicole Pelot³,⁴, Drew DeBay³, Andrea Penwell¹, Genevieve Weir¹, Marc Mansour¹, Chris Bowen,²³

¹Immunovaccine Inc., Halifax, NS, Canada; ²School of Biomedical Engineering, Dalhousie University, Halifax, NS, Canada; ³Institute for Biodiagnostics (Atlantic), National Research Council of Canada, Halifax, NS, Canada; ⁴Electrical Engineering, Dalhousie University, Halifax, NS, Canada

DepoVax^TM is a liposome-in-oil-based vaccine platform that uses tumor-associated antigens (TAA) encapsulated in liposomes and suspended in oil. The oil acts as an adjuvant that increases the potency of the vaccine. By attaching superparamagnetic iron oxide (SPIO) to the TAA and then encapsulating in liposomes, one can visualize the longitudinal biodistribution of the TAA and evaluate whether the TAA slowly clears from the depot site, resulting in a potentiated immune response. To evaluate the longitudinal clearance of the DepoVax^TM vaccine components, mice underwent a C3 (HPV16 model) challenge using SPIO conjugated to the TAA or associated with the lipid.