Figure 1: The optimal ESW intensity promoted proliferation of BMSCs.

(A) Cell survival decreased with higher impulses of ESW, while no significant difference was observed below 500 impulses compared to control. With 5 KV or 10 KV for 250 or 500 impulses ESW treatment respectively, the cell survival was almost the same as control group (a, P > 0.05; b, P < 0.05 as compared to the control group by One-way ANOVA with Student–Newman-Keuls post hoc test). (B) MTT assay indicated that 500 impulses of 10 kV significantly augmented BMSC proliferation within 48 h after ESW treatment. Data are presented as the mean ± SD from triplicate experiments (a, P > 0.05; b, P < 0.05; c, P < 0.001 as compared to control group at the same period by One-way ANOVA with Student–Newman-Keuls post hoc test; n = 6). (C,D) The optimal ESW intensity promoted proliferation of GFP-BMSCs both in vitro and in vivo. GFP-BMSCs with or without ESW treatment were seeded with the same initial density (2,000 cells/well); cells from the ESW-treated group proliferated significantly faster than control cells at both time points (day 1 and 3 in culture; P < 0.001 by unpaired two-tailed Student’s t test, n = 3). (D,E) Dynamic fluorescence of control and ESW treated GFP-BMSCs (1.0 × 10⁶ cells) seeded onto PLGA scaffolds and subcutaneously implanted into nude mice was monitored using an IVIS 200 imaging system. Significantly more cells were retained in vivo in ESW group versus control at weeks 2 post-implantation (P < 0.001 by unpaired two-tailed Student’s t test, n = 3).