CD4 and neoplasm: To this aim, we took advantage of our previous work in which we showed that the immunization of BALB/c mice with bacterial Outer Membrane Vesicles (OMVs) decorated with five CT26 immunogenic epitopes described by Kreiter and coworkers [12] (four CD4+ T cell epitopes (M03, M20, M27 and M68) and one CD8+ T cell epitope (M26)) partially protected mice from tumor growth [16].