Immunophenotypic and morphologic comparison of neoplastic cells from RE;c-Kit^D814V mice with AML, MPN, or pre-B-ALL. (A) Representative FACS analysis of neoplastic cells harvested from BM of Bex;Vex control and moribund RE;c-Kit^D814V mice with the indicated disease phenotype. Cells were gated for Bex⁺Vex⁺ expression and then analyzed for FSC/SSC profiles and Mac-1, Gr-1, B220, and CD19 expression. (B) Wright-Giemsa–stained cytospins of FACS-purified Bex⁺Vex⁺ myeloid scatter-gated or Bex⁺Vex⁺ lymphoid blast scatter-gated BM cells from control or moribund animals (original magnification ×630). Expansion of metamyelocytes, band forms, and eosinophilic progenitors was noted in RE;c-Kit^D814V mice with MPN. Morphology of pre-B-ALL cells in RE;c-Kit^D814V mice was predominantly lymphoblastic. (C) FACS analysis of myeloid-lineage surface markers and Wright-Giemsa–stained cytospin preparation of FACS-purified Vex⁺ myeloid-gated BM cells from a representative moribund animal with c-Kit^D814V+ MPN showing a predominance of maturing granulocytes.