Fig. 1. Bone type H endothelium is reduced upon myocardial infarction (MI).

a Schematic of the experimental design. b, c Flow cytometry analysis of femur bone marrow. Surgery was performed on 12-week-old animals. b Gating strategy for endothelial cells (CD45^negTer119^neg viable single bone cells are shown with further gating on CD31^pos cells, followed by gating of Type H and Type L EC subsets, based on CD31 and Emcn expression). The numbers shown within the gates represent the percentages of events (cells) within that gates relative to the upstream parent gates (CD45^negTer119^neg for CD31^pos cells and CD31^pos cells for Type H and Type L EC subsets, accordingly). Representative samples from control and day (d) 28 are shown. c Quantification. Upper panel, type H endothelial cells are reduced relative to all bone marrow endothelial cells (BM EC) after MI. Lower panel, Long-term hematopoietic stem cells (LT-HSC) are increased relative to LSK cells after MI. N = 8 for control, N = 4 for d1, N = 12 for d3, N = 12 for d7, N = 9 for d14, and N = 10 for d28. Data are shown as mean ± SEM. P-value was calculated with ANOVA with Dunnet’s multiple comparison test. d, e Immunostaining of longitudinal sections through the femur. d The length of type H vessels (measured in µm, indicated by the dashed line) is reduced after MI. N = 3 for control, d3 and d28, and N = 4 for d14. Data are shown as mean ± SEM. P-value was calculated with ANOVA. Comparisons among all groups were calculated by Dunnet’s multiple comparison test. e Myeloid progenitor cell number is increased in the bone marrow 28 days after MI. N = 5 for each condition. Data are shown as mean ± SEM. P-value was calculated by unpaired, two-tailed Student’s t-test.