Fig. 5: Aged and P-cKO mice have MPCs with increased CCL5 expression and increased numbers of TCNs in BM.

a Heatmap of mouse chemokine levels tested using real-time qPCR in bulk RNA extracted from CD45^- cells isolated from BM of 9-mon-old TRAF3^fl/fl (WT) and Prx1^CreTRAF3^fl/fl (P-cKO) mice and 24-mon-old TRAF3^fl/fl (WT) mice. n = 4, 3, and 3 biologically independent male mice, respectively. b, c Cytokine array of BM protein lysate from 2- and 18-mon-old male C57 mice (b) and from 9-mon-old WT and P-cKO male mice (c). d Relative levels of Ccl5 mRNA in bulk RNA from 3^rd passage BM-MSCs from 3- (young; Y) and 22-mon-old (aged; A) male C57 mice. Mean ± SD (n = 3 biologically independent samples/group). e Relative levels of Ccl5 in bulk RNA from human vertebral specimens. Mean±SD (n = 16 young (Y) and 18 elderly (A) human subjects). f, g Sheared chromatin from WT and P-cKO BdMPCs used to perform DNA IP with RelA and RelB Abs or IgG control. RT-PCR using designed primers with putative κB binding sites in Ccl5 gene promotors, normalized to input. Mean±SD (n = 3 biologically independent samples/group). h TNs sorted from BM of 3- (young) and 22-mon-old (aged) male C57 mice attracted by chemokines, including CCL4, CCL5 and CXCL12. Velocity of TN migration. Mean ± SD (n = 20 biologically independent cells). i Frequencies of CCR5⁺ cells in Ly6C^hi6G^- and Ly6C^-6G⁺ cells gated from TGFβ1⁺CD11b⁺ BM cells of 22-mon-old male C57 mice. Mean ± SD (n = 5 biologically independent male mice/group). j Mean fluorescence intensity (MFI) of CCR5 expression by Ly6C^hi6G^- and Ly6C^-6G⁺ subpopulations in TGFβ1⁺CD11b⁺ BM cells from 22-mon-old male C57 mice. Mean ± SD (n = 5 biologically independent male mice/group). k Frequencies of CSF-1R⁺ cells in Ly6C^hi6G^- and Ly6C^-6G⁺ cells gated from TGFβ1⁺CD11b⁺ BM cells of 22-mon-old male C57 mice. Mean ± SD (n = 13 biologically independent male mice/group). l Migration of TNs from 22-mon-old male C57 mice toward WT and P-cKO MPCs upon vehicle or maraviroc treatment tested using a transwell system. Cells maintained in the transwell membrane stained purple and manually marked with black line circles. Bar = 50 μm. m Cells in purple in transwell membrane. Mean ± SD (n = 4 biologically independent samples/group). Analyses: one-way ANOVA with Tukey’s post hoc test in (h) and (m); Student’s two-sided unpaired t test in all others. Source data are provided as a Source data file.