Nrf3-null mice treated with B[a]P exhibit a high incidence of T-cell lymphoblastic lymphoma. (A) Thymus and spleen from a Nrf3^−/− control mouse (left) and from a B[a]P-treated Nrf3^−/− mouse with a T-cell lymphoblastic lymphoma accompanied by splenomegaly (right). Images were captured by a NIKON D70 camera equipped with a Sigma ring flash and processed with Photoshop CS4 (Adobe Systems). (B) Histologic sections of the thymus (top), spleen (middle), and lung (bottom) from a B[a]P-treated Nrf3^−/− mouse with a T-cell lymphoblastic lymphoma were stained with hematoxylin and eosin (original magnification ×200). Bars represent 100 μm. Images were captured by an Olympus Bx-51 microscope equipped with a DP-70 camera. Image analysis was performed using Olympus software. (C) Immunohistochemistry using anti-terminal deoxynucleotidyl transferase and anti-CD3 and anti-CD45 antibodies demonstrates that the malignant lymphoid cells in the thymus (top) and in the lung metastases (bottom) of B[a]P-treated Nrf3^−/− mice are of T-cell origin (original magnification ×400). Images were captured by an Olympus Bx-51 microscope equipped with a DP-70 camera. Image analysis was performed using Olympus software. Bars represent 50 μm. (D) Spectrum of lymphoma subtypes in B[a]P-treated wild type mice versus B[a]P-treated Nrf3-null mice.