Extended Data Fig. 6: HSC proximity to selected niche cell types is not random.
From: Haematopoietic stem cells in perisinusoidal niches are protected from ageing
a, Representative stacked whole-mount images of WT femoral BM showing CD41+ (yellow) MKs and vasculature (red). b, Confocal whole-mount image of WT femoral BM showing perisinusoidal CD41+ (yellow) MKs around sinusoids (red). c, Representative 3D reconstruction for volume occupancy measurements of CD31+ CD144+ ECs in femoral whole-mount images. d, Epiphyseal/metaphyseal and diaphyseal CD31+ CD144+ ECs volume occupancy in young and old long bone BM (upper graph: n = 3 areas per group, from 3 mice per group; lower graph: young n = 9 and old n = 13 areas, from 3 mice per group). The experiments in a-c were repeated two independent times with similar results. In d data represent mean ± s.e.m and the statistical significance was assessed by two-tailed unpaired t-tests. Scale bars, 100 μm (a); 20 μm (b). e-g, Observed (histology) and expected (in silico) distances of HSCs from endosteum (e), Nes-GFPlow cells (f) or MKs (g) in young and aged mice. Statistical differences indicate a non-random distribution of HSCs. h-j, Comparison of the distances of HSCs from endosteum (h), Nes-GFPlow cells (i) or MKs (j) in young and aged mice according histology (observed young vs observed aged) and in silico (expected young vs expected aged) dataset. For e-j two-sample Kolmogorov–Smirnov test was used to analyse significance. Alpha levels were selected to control for sample sizes. Observed distance from Nes-GFPlow cells: aged: n = 135 measurements from two maps; young: n = 94 measurements from two maps. Observed distance from endosteum: aged: n = 432 measurements from 3 maps; young: n = 192 measurements from 3 maps. Observed distance from MKs: aged: n = 163 measurements from 3 maps; young: n = 123 measurements from two maps. Expected distance from Nes-GFPlow cells, endosteum and MKs: aged: n = 10,000 measurements from 3/3/4 maps; young: n = 10,000 measurements from 3/3/5 maps. For further details about the simulation procedure and statistical analysis see Materials & Methods. See also Supplementary Figure 1 and Source Data Extended Data Fig. 6.
