Fig. 4
The 4T1 vaccine abrogates EMT6 immunity. a Female balb/cByJ mice were vaccinated with irradiated 5 × 105 EMT6 cells (EMT6 vaccine) or a homogenous mixture of irradiated 5 × 105 EMT6 and 1 × 106 4T1 cells (ipsilateral hybrid vaccine) or irradiated 1 × 106 4T1 and 5 × 105 EMT6 on opposite flanks (contralateral hybrid vaccine) twice, 10 days apart. Ten days after the booster vaccine, all mice were challenged with 5 × 105 live EMT6 cells on the same side as the irradiated EMT6 cells. Unvaccinated naïve mice challenged with 5 × 105 live EMT6 cells served as controls. Tumor volumes (b) and tumor-free survival (c) were recorded. Differences in survival were compared determined by log-rank analysis. IACUC, Institutional Animal Care and Use Committee