FGF-2 induces expansion of Nestin-expressing MSCs and increases expression level of SCF. C57BL/6 Nestin-GFP mice were treated with PBS or FGF-2 (n = 6). (A) Percentage of BM Nestin⁺/CD45⁻ MSCs as determined by flow cytometry. (B) Representative flow cytometry density plot analysis of BM Nestin⁺/CD45⁻ MSCs. Numbers indicate the percentage of BM Nestin⁺/CD45⁻ MSCs. (C) Percentage of bromodeoxyuridine-positive (BrdU⁺) cells from BM Nestin⁺/CD45⁻ MSCs as determined by flow cytometry. (D) Representative flow cytometry histogram analysis of BrdU incorporation in BM Nestin⁺/CD45⁻ MSCs. Numbers indicate the mean percentage ± SEM of BrdU⁺ cells from BM Nestin⁺/CD45⁻ MSCs. (E) Representative tissue expression of Hoechst, Nestin, and FGFR1/2 in C57BL/6 Nestin-GFP mice BM at steady-state conditions (100×). Scale bar represents 20 μm. (F) Representative flow cytometry histogram analysis of FGFR1/2 expression on BM Nestin⁺/CD45⁻ MSCs. (G) Number of CFU-Fs derived from 2.5 × 10⁶ total BM cells taken from control or FGF-2–treated mice. (H) Representative images of CFU-Fs derived from 2.5 × 10⁶ total BM cells taken from control or FGF-2–treated mice. (I) Number of Nestin-GFP⁺ cells counted in cultures derived from 2.5 × 10⁶ total BM cells taken from control or FGF-2–treated mice. (J) Representative image of Nestin-GFP⁺ cells found in cultures in scattered single-cell appearance (10×). Scale bar indicates 200 μm. (K) Number of Nestin-GFP⁺ adherent mesenspheres counted in cultures derived from 2.5 × 10⁶ total BM cells taken from control or FGF-2–treated mice. (L) Representative image of Nestin-GFP⁺ adherent mesensphere found in cultures (10×). Scale bar indicates 200 μm. C57BL/6 Nestin-GFP mice were treated with PBS or FGF-2 for the indicated time points (n > 4). (M) Percentage of BM SKL (blue) and BM CD45⁻/CD11b⁻/Sca-1⁺/CD29⁺ (red) MSC progenitors as determined by flow cytometry. (N) Percentage of BM SLAM (blue) and BM Nestin⁺/CD45⁻ (red) MSCs as determined by flow cytometry. *P < .05; **P < .01. Data shown are means ± SEM.