A comprehensive study of the interactions between lectins and glycoproteins possessing different glycosylation profiles in the composition of nanoparticles was carried out in order to find specifically interacting protein pairs for the creation of novel classes of multifunctional nanoagets that based on protein-assisted selfassembly. We obtained information about specific interactions of certain lectins with selected glycoproteins as well as about the ability of certain monosaccharides to competitively inhibit binding of glycoproteins with lectins. These protein-mediated interactions may be involved in the formulation of self-assembled nanoparticles for therapy and diagnostics of various diseases.