The hematopoietic defects of Δ^Lyl1/Δ^Lyl1 mice are not responsible for the accelerated tumor growth and immaturity of tumor blood vessels. (A top) Shown is the volume of LLC tumors implanted in C57Bl/6 Ly5.1 mice transplanted with bone marrow cells from Δ^Lyl1/Δ^Lyl1 or WT C57Bl/6 Ly5.2 mice, as a function of time. Eight weeks after transplantation, 86.9% (± 5.5%) and 77.4% (± 8.2%) of PBMCs were Ly5.2-positive in mice transplanted with BM cells from either WT or Lyl1-deficient mice, respectively. Error bars represent means ± SEM, WT (n = 9); Δ^Lyl1/Δ^Lyl1 (n = 7). (Bottom) Quantization of mural cell coverage of tumor blood vessels of WT mice transplanted either with WT or Δ^Lyl1/Δ^Lyl1 mice BM cells, by immunofluorescence with NG2, or α-SMA antibody. Vessel coverage was calculated as the percentage of NG2-, or α-SMA, positive vessels compared with the number of CD31-positive vessels. The data are presented as the mean ± SEM. Analyzed individual tumors: WT (n = 5); Δ^Lyl1/Δ^Lyl1 (n = 6); NG2 coverage: 70% (± 9.2%) and 72.2% (± 13.8%) for WT mice transplanted with WT and Lyl1-deficient BM cells, respectively; α-SMA coverage: 34.8% (± 5.8%) and 46.5% (± 9.5%) for WT mice transplanted with WT and Lyl1-deficient BM cells, respectively. (B top) Shown is the volume of LLC tumors implanted in C57Bl/6 Ly5.2 WT and Δ^Lyl1/Δ^Lyl1 mice transplanted with fetal liver cells from C57Bl/6 Ly5.1 WT mice, as a function of time. Six weeks after transplantation, 77.6% (± 9.1%) and 92.8% (± 1.9%) of PBMCs were Ly5.1-positive in Ly5.2 WT or Lyl1-deficient transplanted mice, respectively. Error bars represent means ± SEM, WT (n = 6); Δ^Lyl1/Δ^Lyl1 (n = 9). *P < .05. (Bottom) Quantization of mural cell coverage of tumor blood vessels of either WT or Δ^Lyl1/Δ^Lyl1 mice transplanted with WT fetal liver cells by immunofluorescence (as in panel A). The data are presented as the mean ± SEM. Analyzed individual tumors: WT (n = 6); ΔLyl1/ΔLyl (n = 6); NG2 coverage: 59.6% (± 7.8%) and 10.5% (± 4.3%) for WT and Δ^Lyl1/Δ^Lyl1 mice transplanted with WT FL cells, respectively. For α-SMA coverage: 32.4% (± 11.7%) and 5.6% (± 2.5%) for WT and Δ^Lyl1/Δ^Lyl1 mice transplanted with WT FL cells, respectively.