CD19 and B-cell neoplasm: In the DLBCL group, which is characterized by large cells (FSCH) expressing CD45R/B220 and CD19, we also found examples of mice with B cell neoplasms showing a prominent starry sky pattern, positive staining for BCL6, MUM-1, and CD10 and a high proliferation index, as shown by Ki67 staining, consistent with a high-grade B-non Hodgkin lymphoma (NHL) (Supplementary Figure 2).