Figure 4. Aged Vwf⁺ LT-HSCs show increased intrinsic myeloid bias at the population level.

(a) Experimental design to compare in vivo lineage output of transplanted young and old Vwf⁺ and Vwf⁻ LT-HSCs. (b) Donor contribution of young and old Vwf⁻ and Vwf⁺ LT-HSCs to total peripheral blood leucocytes at 16 week post-transplantation. Young Vwf⁻: N=5; young Vwf⁺: N=11; old Vwf⁻: N=9, old Vwf⁺: N=12). E⁻: Vwf-EGFP⁻; E⁺: Vwf-EGFP⁺. Data are from four independent competitive transplantation experiments. (c) Donor contribution to peripheral blood platelets measured at 16 week post-transplantation in experiments described in b. (d) Relative contribution of test cells to output of myeloid (left panel) and lymphoid (right panel) cells at 16 weeks post-transplantation from experiment described in b. Values were normalized to the level of CD45.2 chimerism (b) and are expressed relative to young Vwf⁻ recipients (=1). (e) Test cell contribution to BM LSKCD150⁺CD48⁻CD34⁻ LT-HSCs in mice from b 22 weeks after transplantation. E⁻, Vwf-EGFP⁻; E⁺, Vwf-EGFP⁺. Data are from three independent experiments. All data are mean values±s.e.m. *P<0.05; **P<0.01; ***P<0.001 (Student's t-test).