Figure 2. MPN that developed in Ptpn11^E76K/+Vav1-Cre⁺ mice is less severe and less progressive than MPN developed in Ptpn11^E76K/+Mx1-Cre⁺ mice.

Ptpn11^E76K/+Mx1-Cre⁺ and Ptpn11^+/+Mx1-Cre⁺ mice (8 weeks after pI–pC administration), along with 16-week-old Ptpn11^E76K/+Vav1-Cre⁺ and Ptpn11^+/+Vav1-Cre⁺ mice were killed. a, Spleen weights were determined (n = 8 mice per group). b, Cells isolated from BM, spleens and livers were assayed for Mac-1⁺Gr-1⁺ myeloid cells (n = 8 mice per group). c, Ptpn11^E76K/+Mx1-Cre+ and Ptpn11^E76K/+Vav1-Cre⁺ mice administered with pI–pC were monitored for 12 months for acute leukaemia progression. d, Haematopoietic cells (CD45⁺), MSPCs (Sca-l⁺CD140α⁺CD45⁻Ter-119⁻CD31⁻), endothelial cells (CD45⁻Ter-119⁻CD31⁺), and osteoblasts (Sca-l⁻CD140α⁺CD45⁻Ter-119⁻CD31⁻) were sorted from the BM.

The abundance of the neo cassette in genomic DNA was determined by qPCR (n = 3 mice per group). e–h, BM cells collected from wild-type BoyJ mice were transplanted into Ptpn11^E76K/+Mx1-Cre⁺, Ptpn11^+/+Mx1-Cre⁺ (8 weeks following pI–pC treatment), and Ptpn11^E76K/+Vav1-Cre⁺ (16 weeks old) mice. Recipients were monitored for MPN development for 6–8 months (e). Mac-1⁺Gr-1⁺ myeloid cells in the BM, spleen and liver were examined (n = 5 mice per group) (f). The pool size (n = 4 mice per group) (g) and intracellular signalling activities (n = 3 mice per group) (h) of donor HSCs were determined 25 weeks following transplantation. Data shown in a, b, d, f–h are mean ± s.d. of all mice examined. Statistical significance was determined between Ptpn11^E76K/+Mx1-Cre⁺ and Ptpn11E76K/+Vav1-Cre⁺ groups; **P < 0.01; ***P < 0.001. Source Data for this figure are available online.