Loss of TLR2 accelerates leukemogenesis in the NHD13 mice. (A) Representative flow plots of TLR2 surface expression on the bone marrow lineage⁻ c-Kit⁺ Sca-1⁺ (KSL) cells of WT and NHD13 mice. A TLR2 FMO control was included as a negative control. These data are quantified in panel B, which shows the MFI values for each of the samples analyzed (n = 6 mice/group, age 6-8 weeks). (C) Kaplan-Meier survival curve of NHD13;Tlr2^+/+ (n = 16), NHD13;Tlr2^−/− (n = 23), Tlr2^−/− (n = 16), and WT mice (n = 7). *P = .03 by the Gehan-Breslow-Wilcoxon test and .07 by log-rank (Mantel-Cox) test comparing NHD13;Tlr2^−/− with NHD13;Tlr2^+/+. (D) TLR2 surface expression was assessed by flow cytometry on bone marrow KSL cells of 6- to 8-week-old (preleukemic) WT vs NHD13 mice (left) and the bone marrow blast cells of leukemic NHD13 mice compared with the c-Kit⁺ cells of healthy WT controls (right). A TLR2 FMO was included as a negative control. Data for each mouse analyzed are plotted in panel E, with each data point representing the MFI of the NHD13 cells (KSL cells or blasts) normalized to the MFI of WT cells (KSL cells or c-Kit⁺ cells for preleukemic HSPCs and blasts, respectively) run at the same time. n = 6-7 mice/group. Error bars represent mean ± standard error of the mean. FMO, fluorescence minus one; MFI, median fluorescence intensity.