ubiquitinated proteins enriched by Vx3 conjugated Alpha-alumina nanoparticles induce efficient anti-tumor response

Abstract Weak and ineffective therapy of malignant tumor threatened thousands of people. Immune therapy is one of the most promising methods for tumor treatment due to little side effects. Our previous study has shown that ubiquitinated proteins from tumor cells enriched by Vx3 (A7) protein have an effective anti-tumor efficacy through establishing mice tumor models. However, it was difficult to enrichment ubiquitinated proteins in this methods. Here, we reported that such kind of problem could be solved through a microparticle precipitate method by using a-Al2O3 nanoparticles. Briefly, a-Al2O3 was first functionalized with (3-Aminopropyl) triethoxysilane, and subsequently with glutaraldehyde, as proved by the Fourier transform-infrared (FT-IR) analysis. Finally, the Vx3 (A7) protein was conjugated with the aldehyde-functionalized a-Al2O3 via Schiff ‘ s base reaction. Using Vx3 (A7) protein conjugated with a-Al2O3 could effectively enrich much more ubiquitinated proteins compared with our previous study as indicated by western blot. Interestingly, the ubiquitinated proteins that enriched by this new strategy show a high tumor specific immune response and an effective anti-tumor efficacy through in vivo experiments. It could be concluded that this ubiquitinated-protein conjugated to a-Al2O3 nanoparticles are considered to be a good choice in cancer immunotherapy.