Dendritic cells pulsed with glioma lysates induce immunity against syngeneic intracranial gliomas and increase survival of tumor-bearing mice

Abstract

In recent years, the use of dendritic cells (DC), the most powerful antigen presenting cells, has been proposed for the creation of vaccines against gliomas. This approach has been demonstrated to be safe and non-toxic in phase I or I-II trials (2, 3). Immunotherapy plays a central role in the search for new treatments for glioblastoma multiforme (GBM). In particular, several phase I studies have been performed using DC pulsed by GBM proteins as a vaccine for patients with relapsing GBM. The studies demonstrated that DC vaccination is safe and may produce a significant increase in overall survival. As the first step in the preparation of appropriate conditions for a clinical evaluation in Italy, we have performed pre-clinical experiments on immune-competent mice injected intra-cerebrally with syngeneic GL261GBM cells and treated subcutaneously and intra-tumorally with DC loaded with a GL261 homogenate. These results show that vaccination with DC pulsed with a tumor lysate increases considerably survival in mice bearing intracranial glioblastomas and supports the development of DC-based clinical trials for patients with glioblastomas that do not respond to standard therapies.