This invention describes ways of obtaining nano-particulated adjuvants formed by different synthetic variants of GM3 ganglioside. Depending on the fine structure of the fatty acid in the ceramide of the synthetic GM3, said adjuvants are able to stimulate specifically and in a specialized way the humoral or cellular immune response against accompanying antigens. Particularly, this invention provides immunogenic vaccine compositions that comprise peptides, polypeptides or proteins and the aforementioned nanoparticles, which are formed through the dispersion of hydrophobic proteins of the outer membrane complex (OMC) ofNeisseria meningitidisin solutions containing fully synthetic variants of the GM3 ganglioside.