CD8A and central nervous system cancer: There was also a significant increase in the percentage of IFNγ-expressing T cells in response to the GP33 epitope (comparing CT2A-gp33 vs. CT2A) in brains from non- LCMV infected naïve mice, showing that the GP33 antigen could effectively prime brain-infiltrating CD8+ T cells against CT2A-gp33 gliomas in brain (Fig. 3D).