Enhancement of Wound Healing Efficacy by Increasing the Stability and Skin‐Penetrating Property of bFGF Using 30Kc19α‐Based Fusion Protein

Abstract

involvement in tissue growth and regeneration, including wound healing. Activation of FGF receptor by bFGF stimulates intracellular signaling pathways such as phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) and mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK) signaling pathways which are related to the mitogenic response of cells. [1] As bFGF acts on various target cells involved in wound healing, its effects on wound healing have been extensively studied. [2] bFGF promotes the migration of dermal fibroblasts, keratinocytes, and endothelial cells, into wound sites and facilitates their proliferation. [3] As a result, bFGF accelerates granulation tissue formation and angiogenesis, which results in matrix formation and remodeling. [4] In recent years, a number of clinical uses of recombinant bFGF have been reported, and these include treatment of chronic wounds, second-degree burns, pressure ulcers, and diabetic foot ulcers. [5] However, its inherent instability and rapid degradation often require frequent treatments in tandem with higher concentrations. [6] The reported half-life of recombinant bFGF is less than 10 h under normal cell culture conditions and even shorter in the living organisms, which significantly limits The instability of recombinant basic fibroblast growth factor (bFGF) is a major disadvantage for its therapeutic use and means frequent applications to cells or tissues are required for sustained effects. Originating from silkworm hemolymph, 30Kc19α is a cell-penetrating protein that also has protein stabilization properties. Herein, it is investigated whether fusing 30Kc19α to bFGF can enhance the stability and skin penetration properties of bFGF, which may consequently increase its therapeutic efficacy. The fusion of 30Kc19α to bFGF protein increases protein stability, as confirmed by ELISA. 30Kc19α-bFGF also retains the biological activity of bFGF as it facilitates the migration and proliferation of fibroblasts and angiogenesis of endothelial cells. It is discovered that 30Kc19α can improve the transdermal delivery of a small molecular fluorophore through the skin of hairless mice. Importantly, it increases the accumulation of bFGF and further facilitates its translocation into the skin through follicular routes. Finally, when applied to a skin wound model in vivo, 30Kc19α-bFGF penetrates the dermis layer effectively, which promotes cell proliferation, tissue granulation, angiogenesis, and tissue remodeling. Consequently, the findings suggest that 30Kc19α improves the therapeutic functionalities of bFGF, and would be useful as a protein stabilizer and/or a delivery vehicle in therapeutic applications.

MicroRNA-155 mediates multiple gene regulations pertinent to the role of human adipose-derived mesenchymal stem cells in skin regeneration

“…FGF2 stimulates angiogenesis and enhances the production of ECM proteins, which are essential for tissue repair in the formation of granulation tissue. The mitogenic and angiogenic properties of FGF2 enable its role in tissue remodelling and neovascularization ( Lee et al, 2021 ). FGF2 is known to induce neoangiogenesis during tissue repair, tissue engineering and wound healing through stimulating the differentiation of AD-MSCs into endothelial cells ( Mazini et al, 2020 ), or through enhancing the ingrowth of blood vessels by directly incorporating FGF2 in bioengineered scaffolds ( Shahin et al, 2020 ).…”