Abstract
We designed a novel and simple protein delivery system for cancer immunotherapy : cholesteryl group-bearing polysaccharides, pullulan (CHP), complexed with antigen protein such as HER2/neu and NY-ESO-1 cancer/testis antigen. This unique hydrophobized polysaccharide helps soluble antigen protein to induce cellular immunity, both CD8+T cell and CD4+T cell dependent. Hence, such a novel vaccine may be of potential benefit to cancer therapy. Multi-institutional phase I clinical trials of CHP-HER2 and CHP-NY-ESO-1 have been conducted for patients with refractory cancer. Along with its safety evaluation, CD8+T cell and/or CD4+T cell dependent specific immune responses became detectable in vaccinated patients. Clinical responses were also observed in some patients.
