Immune responses against Lewis Y tumor-associated carbohydrate antigen displayed densely on self-assembling nanocarriers.

Immune responses against Lewis y (LY) displayed on nanocarriers at different surface densities were studied. The high surface density of LY was obtained by the A2B-type amphiphilic polypeptides having LY at the two terminals [LY-poly(sarcosine)2-b-(l- or d-Leu-Aib)6]. The equimolar mixture of these two amphiphilic polypeptides formed interdigitated planar sheet-like molecular assemblies densely displaying LY (G4). G4 seemed to induce the anti-LY IgM upon immunization to BALB/c mice by only a single administration. However, the amount of anti-LY IgM produced was moderate and significantly less than that induced by two administrations of the other molecular assembly (G1) with the average surface density of LY at a 1/4 of that of G4. Further, the anti-LY IgM produced after two administrations of G4 lowered the avidity more than after one administration.