Her2MPtVLP immunized normal and CD8−/− single knock-out C57Bl/6 mice were protected against tumour outgrowth (p<0.05 and p<0.01, respectively), indicating that these groups of mice could mount an immune response after Her2MPtVLP immunization, while most unimmunized mice developed tumours (Table 1). The gene discussed is CD8A; the disease is neoplasm.