Comparison of the immunogenicity of wasp venom peptides with or without carbohydrate moieties

Abstract Three synthetic vespulakinin analogues either with or without carbohydrate moieties and mastoparan B isolated from Vespa basalis venom were investigated for their immunogenic activity and solution conformation. Mice immunized with these wasp venom peptides, with the exception of (Gal α )Thr 3 , (Gal α )Thr 4 -vespulakinin 1, showed positive antibody responses. However, the response elicited by mastoparan B was much higher than those induced by vespulakinin analogues. The class of antibody induced by these peptides was identified as an IgG 1 isotype with κ -light chain, suggesting stimulation of a T-cell-dependent immune response by these peptides. According to the circular dichroism spectra of these peptides, the structures of the vespulakinin analogues in solution were largely unordered, while mastoparan B exhibited a conformation rich in α -helices. The presence of carbohydrate moieties and the rather random structure in vespulakinins may interfere with T-cell recognition of the peptides, leading to lower immune responses.