Research Article

MSC-Derived Exosome Promotes M2 Polarization and Enhances Cutaneous Wound Healing

Figure 4

MSCs enhance wound healing through exosomes. (a) Representative light field photographs of cutaneous wounds after treatment with PBS, BMMSCs, BMMSC-ex, and BM/siRab27a (a1); the whole cutaneous wound is outlined in a dashed line. Percentage of the wound closure on day 3 to day 12 in reference to the day 0 wounds (a2) (). BMMSC- and BMMSC-ex-treated wounds showed a statistically significant increase in wound closure comparing with the PBS-treated wounds, whereas BM/siRab27a-treated wounds had no significant difference comparing with the PBS group at different time points. (b) Representative H&E image from a cutaneous wound at day 12, the green arrows indicating the margin of wound-healing area. (c) Masson trichrome (c1) showing collagen deposition at day 12 and quantification of collagen index (c2) (). (d) CD31 and PCNA staining of the skin wound at day 12. (e) Quantification of immunostaining of CD31- and PCNA-positive cells at day 12 of the skin wound (). Scale bars: 500 μm (b) and 50 μm (c, d). , , and . Error bars are .