Analysis of BM progenitors in diseased mice and littermates. (A-D) Colony formation assay data. Unfractionated BM nucleated cells (WBM) were collected from PtenΔ/ΔNf1^LOH mice with JMML and littermates at PND17-19 or from mice with CMML at age 2 to 3 months when they were moribund. Data from CFU-GM showed that GM-CSF and IL-3 sensitivities were significantly increased in BM cells from PtenΔ/Δ Nf1^LOH mice with JMML compared with juvenile littermates, whereas Pten^+/ΔNf1^LOH mice showed GM-CSF hypersensitivity only as adults. (E) Flow cytometry analysis of hematopoietic progenitors in BM from juvenile mice. WBMs from PtenΔ/ΔNf1^LOH mice with JMML and littermates at PND17-19 were analyzed by flow cytometry; data demonstrated that lineage (LIN)-negative cells (negative for Gr1, CD3, B220, and Ter119) and LIN⁻Sca1⁺cKit⁺ cells (LSK) were significantly increased in PtenΔ/ΔNf1^LOH mice with JMML, whereas hematopoietic progenitor cells (HPCs; LIN⁻Sca1⁻cKit⁺) were decreased. Data are mean ± standard error. *P < .05, **P < .01, ***P < .001.