Study of the biological function and penetration pathways of the mouse epidermal growth factor ethosomal delivery...

Biological agents are becoming increasingly popular for therapeutic applications in epidermal diseases. Ethosomes facilitate the transdermal/topical delivery of biological macromolecules. The mouse epidermal growth factor (mEGF) was selected as the model biological agent. The aim of this experiment was to determine the penetration pathways and biological functions of the mEGF ethosomal delivery system after its topical application. The mEGF ethosomal delivery system was topically applied on the dorsal skin of C57BL/6 mice at different time points. Freshly excised skin samples were obtained by skin biopsies and shock-frozen, and immunofluorescence was performed. The results showed that penetration of mEGF ethosomes was mainly through the pilosebaceous unit and partly through the intercellular domain. Biological agents encapsulated in the ethosomal delivery system could reach each site of the pilosebaceous unit. We also found that mEGF ethosomes had caused successful transition of the hair follicles from the telogen to the anagen phase of the hair cycle.