CD4 and thymus lymphoma: Upon further examination, 100 days after ENU injection, 83% of the Ripk3−/‐ mice had an abnormal thymus, compared to 50% of Ripk3+/+ mice, thus reflecting the phenotype of early thymic lymphoma (as observed by the subpopulation of CD4 and CD8 by flow cytometry analysis, Architecture of medullar and cortex by H&E staining analysis) (Figure 3C).