A fraction of recipient mice that received transplants of total bone marrow cells expressing oncogenic Kras from its endogenous locus developed thymic T-cell lymphoblastic lymphoma. (A) Representative histopathology (original magnifications of camera lenses used to take the picture listed in parentheses) from thymus (× 100) stained with hematoxylin and eosin (H&E) showed development of thymic lymphoma in mice that received transplants of bone marrow cells expressing oncogenic Kras G12D from its endogenous locus. (B,C) Flow cytometry analysis of thymocytes or purified DN cells isolated from the thymus of control mice or mice that received transplants of bone marrow cells expressing oncogenic Kras. These density plots were gated on live nucleated cells based on forward scatter and propidium iodide staining profiles. More than 98% of the cells analyzed here are donor-derived as judged by their CD45.2 expression. Representative data are shown. The percentages of cells in quadrants of interest are indicated.