Introduction: Glioblastoma multiforme (GBM) is the most common primary malignant brain tumor with an overall survival around 14 months. Recent studies have found that a ribonucleoprotein Vault Nanoparticle can effectively enclose an antigen and potentially stimulate the host’s native immune responses against targeted tumors. In this laboratory investigation, we successfully bioengineered an antigen associated Vault Nanoparticle vaccine targeting glioblastoma and analyzed its ability to stimulate an immune response through dendritic cells and activating T cells in vitro.
Methods: Using INT fusion proteins, GP100 (25-33) cDNA was integrated into a bioengineered CP-Z vault nanoparticle. The recombinant CP-Z-GP100 vault nanoparticle vaccine were used to immature DCs cultured from C57BL/6 mouse bone marrow. Uptake of the antigen vault nanoparticles was analyzed with fluorescent microscopy. After GP100 specific T cells were exposed to antigen vault nanoparticle treated DCs, subsequent T cell activation was assessed using an IFN-gamma ELISA assay.
Results: Recombinant vault nanoparticles were internalized by DCs and processed for antigen presentation resulting in activated DCs. Flow cytometry demonstrated statistically significant increases in CD86, a marker for dendritic cell maturation. After treatment with the antigen nanoparticle vaccine, these DCs were then co-cultured with GP100 antigen specific T cells, and IFN-gamma levels were measured via an ELISA assay. T cells cultured with the antigen vault nanoparticle vaccine treated dendritic cells had an IFN gamma concentration that was significantly greater than either controls, the empty vaults or untreated dendritic cells (1.58 ng/mL vs. 0.07 ng/mL or 0.72 ng/mL respectively).
Conclusions: Our laboratory investigation suggests that an immune response through T cells can be successfully activated utilizing an antigen vault nanoparticle vaccine. These nanoparticles demonstrate effective maturation of dendritic cells in vitro and significant activation of a specific antigen T cells with IFN gamma upregulation. This data demonstrates that a vault nanoparticle vaccine may represent a promising novel form of immunotherapy against brain cancer.
Patient Care: Identify a novel immunotherapy vault nanoparticle against brain cancer
Learning Objectives: Assess the potential use of vault nanoparticle vaccine against brain cancer