Figure 3.

Prx1  ⁺ (A-C) and Hic1⁺ (D) MPC lineage tracking (LT) in skeletally mature mice (4-month post-tamoxifen induction). Individual GFP (Prx1), Tomato (Prx1LT), and Ki67 channel images (B/C’, B/C’’, B/C’’’) are presented to demonstrate that the Prx1⁺ LT cells remain undifferentiated. The dura mater is outlined by the dashed line while the epidural fat is encircled by the solid line. Arrows indicate examples of Prx1⁺ and Hic1⁺ cells in the dura mater. An individual Ki67 channel image (D) is presented to demonstrate that the Hic1⁺ LT cells remain proliferative. The dura mater is outlined by the dashed line while the epidural fat is encircled by the solid line (C). Quantification of Prx1⁺ and Hic1⁺ MPCs within the dura mater and epidural fat (E). An n = 3 mice were used per group per time point. ∗P < .05. Scale bars = 100 µm (A, C) and 50 µm (B-B’’). Abbreviations: GFP, green fluorescent protein; Hic1, hypermethylated in cancer 1; MPCs, mesenchymal progenitor cells; Prx1, paired related homeobox-1.