IRF8 and lymphoma: Moreover, mutations in interferon regulatory factor 8 (IRF8) in lymphoma impair the expression of CD74 and HLA‐DM—critical intracellular regulators of MHC‐II antigen processing and peptide loading—resulting in defective antigen loading onto MHC‐II complexes, diminished CD4+ T cell activation, and enhanced immune evasion.98