The development of potent adjuvants, conditioning innate and adaptative immunity, particularly CTL responses, has become currently a hot point in the rational design of vaccines for cancer immunotherapy. We have described a new approach, in which gangliosides are incorporated into vesicles from Neisseria meningitidis to form Very Small Size Proteoliposomes (VSSP). VSSP is a good alternative to the existing adjuvants for use in whole cells vaccines since it promotes 80% tumour rejection and growing delay in the CT26 and F3II tumour models respectively. Also VSSP induces activation of CTL responses to co-injected trimmed peptides and soluble proteins. This phenomena is facilitated by the cross-presentation of exogenous antigen and do not need cooperation of CD4 T cells for primary CD8 T cells expansion. © 2005 Elsevier Ltd. All rights reserved.