Histopathologic and immunohistochemical characteristics of the DTG lymphomas in relation to the B-cell lymphomas in parental IL-14α TG and c-myc TG mice. (A) H&E-stained paraffin sections (original magnification, × 400). (B) Sections stained with anti-B220 (original magnification, × 400). (C) Sections stained with anti–cyclin D (original magnification, × 400). DTG tumor staining is more uniform and intense than that of the c-myc TG tumor. IL-14α TG tumor is negative. (D) Flow cytometry of tumors from IL-14α TG, c-myc TG, and DTG mice showing CD19/CD5 and CD19/sIgM staining. (E) Semiquantitative RT-PCR of C57/BL6 spleen and tumors from IL-14α TG, DTG, or c-myc TG mice analyzed for cyclin D1 and actin, as described in “Patients, materials, and methods.” (F) Immunoglobulin gene rearrangements performed on tumors from IL-14α TG, c-myc TG, and DTG mice showing monoclonality of all of these tumors, as described in “Patients, materials, and methods.”