Lymphomas from Eμ-MycT/+;Bcl-w+/+, Eμ-MycT/+;Bcl-w+/−, or Eμ-MycT/+;Bcl-w−/− mice were immunophenotyped by staining for the B cell lineage surface markers IgM, IgD, CD19, and B220 (B220+IgM−IgD− identifies pro-B/pre-B cells, B220+IgM+IgD− identifies immature B cells, and B220+IgM+IgD+ identifies mature B cells). Here, CD19 is linked to lymphoma.