CD8A and neoplasm: Additionally, upon ex vivo restimulation with cognate antigen, we found that tumor-specific Fcgr2b–/– CD8+ OT-I T cells exhibited a significant increase in the frequency of IFN-γ+ TNF+ double cytokine producers in both the dLN (Figure 4, H and I) and the spleen (Figure 4, J and K) on day 10.