The majority of recipient mice transplanted with whole bone marrow cells expressing oncogenic Nras developed a CMML-like disease. (A) Dynamic percentages of donor-derived monocytes and neutrophils in peripheral blood of diseased mice transplanted with Nras G12D cells or control mice transplanted with control cells. (B) Splenomegaly and hepatomegaly in diseased mice. (Top) Splenomegaly in a representative recipient mouse that developed a CMML-like disease. (Bottom) Results are presented as averages of spleen weights or liver weights + SD. (C) Representative histologic hematoxylin and eosin–stained sections from spleen showed an extensive infiltration of myelomonocytic cells and extramedullary hematopoiesis in recipient mice transplanted with bone marrow cells expressing oncogenic Nras. (D) Flow cytometric analysis of bone marrow cells and splenocytes using myeloid specific markers (Mac1 and Gr1). The percentages of monocytic (top left) and granulocytic (top right) lineages of cells are indicated on the plots. Representative data from 8 CMML mice are shown. (E) Quantification of monocytes (W1) and neutrophils (W2) in peripheral blood were based on their surface expression of Mac1 and Gr1. The right panels show May-Grunwald Giemsa–stained cytospin preparations of cells sorted from W1 and W2 regions to confirm the identities of cells.