Figure 4: Effects of Hibiscus syriacus L. flower (HSF) absolute on sprout formation on HaCaT cells. (a) Cells were mixed with collagen and then placed into 24-well plates. Spots were treated with recombinant human epidermal growth factor (EGF; 50 ng/mL) or HSF absolute 0.1 mg/mL for 72 h. Spots and sprout outgrowth cells were stained with Diff-Quick solution and then images were obtained using microscopy (× 100). EGF was used as a positive control. (b) The statistical results were obtained from panel A. The level in the quiescent state is expressed as 100% (n = 4). Data are expressed as the mean ± SE.