Here, we isolated T cells from the OT-I T cell receptor (TCR) transgenic mice, which recognizes OVA residues 257 to 264 in a MHCI-restricted context (55), and quantified the resulting CD8 activation/differentiation in vitro by measuring their cytotoxicity toward isogenic IRF8-WT or KO murine B cell lymphoma cells. This evidence concerns the gene IRF8 and B-cell non-Hodgkin lymphoma.