CD8A and neoplasm: While the F1 cross-presentation model precludes any assessment of tumor regression due to the inability of direct antigen presentation, the increase in the proportion of CL4 CD8+ T cells associated with gemcitabine treatment and their ability to express IFNγ correlates to our earlier studies in which these CL4 cells drive an anti-tumour response against CL4 bearing tumours [25], [31].