Fig. 7

Angiogenic activity of HSA-bFGF NPs in vitro and in vivo. (A) Observation of angiogenic tube formation process of the HUVECs. Images showed sprouting from the HUVECs as indicated (red dotted circles). The HSA-bFGF NPs-treated cells maintained sprouting activity until 8 h. Scale bars, 50 μm. (B) In vivo angiogenesis evaluation through CAM assay. Extended blood vessel formation in fertilized eggs was observed upon treatment with HSA-bFGF NPs, compared with the other groups. Photographic images were taken at day 0, 4 and 6. (C, E) Immunofluorescence analysis of angiogenesis in the skin wound in vivo. Angiogenic efficacy was validated through observation of blood vessel formation in wounded area of rats. Blood vessels (magenta) and nuclei (cyan) in the dermis and hypodermis were stained with fluorescence labelled CD31 antibody and Hoechst 33342, respectively. Wound was treated with HSA NPs, soluble bFGF, and HSA-bFGF NPs at the bFGF contents of (C) 12.5 µg and (E) 3 µg, respectively. Scale bar, 50 μm. (D, F) Quantitative analysis of blood vessel numbers in wound area. HSA-bFGF NPs showed superior healing capability over any other groups, in accordance with macroscopic analysis. n.s. not significant. * p < 0.05 and ** p < 0.01. n = 3