1363 Multilamellar mRNA lipid particle aggregate vaccines safely reprogram the tumor microenvironment and induce objective radiographic response in canines de réir Duane A Mitchell, John A Ligon, Duy Nguyen, Paul Castillo, Natalie Silver, W Gregory Sawyer, Brian Stover, Frances Weidert, Adam Grippin, Lana Fagman, Jonathan Chardon-Robles, Gabriel Jobin, Chao Xie, Nicholas Diodati, Joanne Lagmay, Leighton Elliott, Eugene Hwang, Michael Isakoff, Lars Wagner, Rowan Milner, Hector Mendez-Gomez, Study Staff, Elias Sayour