EXTH-09. GM-CSF AND IL-7 FUSION CYTOKINE ENGINEERED TUMOR VACCINE GENERATES LONG-TERMTH-17 MEMORY CELLS AND INCREASES OVERALL SURVIVAL IN AGED SYNGENEIC MOUSE MODELS OF GLIOBLASTOMA

Abstract

Abstract Age-related immune dysfunctions, such as decreased T-cell output, are closely related to pathologies like cancers and lack of vaccine efficacy among the elderly. Engineered fusokine, GIFT-7, a fusion of IL-7 and GM-CSF, can reverse aging-related lymphoid organ atrophy. We generated a GIFT-7 fusokine tumor vaccine and employed it in aged syngeneic mouse models of glioblastoma, and found that peripheral vaccination with GIFT-7TVax resulted in thymic regeneration and generated durable long-term anti-tumor immunity specifically in aged mice. Global cytokine analysis showed increased pro-inflammatory cytokines including IL-1b in the vaccinated group that resulted in hyperactivation of dendritic cells. In addition, GIFT-7 vaccination resulted in increased T-cell trafficking to the brain and robust Th-17 long-term effector memory T-cell formation. TCR-seq analysis showed increased productive frequency among detected rearrangements within the vaccinated group. Overall, our data demonstrate that aging immune system can be therapeutically augmented to generate lasting anti-tumor immunity.