Figure 2

Protection from tumor challenge after vaccination with virus-like replicon particles (VRP)-neu. Groups of seven or eight mice were vaccinated three times at 2-week intervals with VRP-neu or VRP-hemagglutinin (HA). Two weeks after the final vaccination, the mice were challenged with A2L2 cells injected into a mammary fat pad. Five weeks after the tumor challenge, (a) the largest dimension of each tumor was measured and (b) the mice were killed and the mass of the tumor in each animal was determined.