“…51−53 While it is the previously demonstrated pro-angiogenic effect of FE 10 that initiated our current effort for engineering pro-vasculogenic fibers, increasing evidence suggests that our FE, derived from healthy young women of different ages (22−35 years old) 10,54 in different locations of the body (e.g., abdomen, thighs, and upper arms) 11 with relatively stable concentrations of the major growth factors, has omnipotent biological functions in the treatment of different diseases, such as ischemic stroke, 43 osteoporosis, 55 osteoarthritis, 56 spinal cord injuries, 14 chronic wound healing, 13 reproductive related disorders, 38,57 and so on. With the multifaceted actions identified in FE, in tandem with its cell recruitment capability observed in our current study (Figures 4E,F and S1) and elsewhere, 44 the FE-PDA@PCL/GT fiber system will be well suitable for engineering 3D fibrous scaffolds 58,59 for in situ regeneration of different tissues. From the perspective of FE as a biological therapeutic agent, the advantages of high drug-loading efficiency and prolonged FE-releasing profile in the FE-PDA@PCL/GT fibers may offer new strategies for addressing the FE delivery issues.…”