Construction Of Skin Organoids And Repair Of Large-area Skin Wound

The skin is the first barrier of the human body.When the skin is seriously damaged,such as burns,it will damage its regeneration ability.There are also risks such as infection,chronic ulcer,organ failure and even life-threatening.Therefore,the repair of skin damage is of great significance to ensure human health.At present,the transplantation of skin substitutes is used for the repair of trauma in clinic,among which the skin substitutes with physiological correlation can better promote the repair of wound.Skin organoid is a 3D model in vitro.It is a tissue like organ with similar structure and function to skin tissue.In the process of skin tissue repair and skin regeneration,it is most closely related to epidermal stem cells.Therefore,in this study,we isolated and extracted epidermal stem cells with dry potential from samples,and then used epidermal stem cells to constructskin organoids through three-dimensional culture.The organoids were sectioned and stained,and compared with normal skin tissue structure,The results showed that theskin organoids we constructed had a certain skin structure.Skin organoids and 2D cultured epidermal stem cells were transplanted into the wound of mouse model of large-area skin injury.The effects of organoids and epidermal stem cells on wound repair were observed with no cells or organoids as negative control.The results showed that compared with the negative control group,the transplantedskin organoids group and 2D cultured epidermal stem cells group could promote wound closure in the early stage of wound repair.In this study,the wound tissue was further collected,and the re epidermization and accessory organ repair of the wound were statistically compared by H &E staining,immunohistochemistry and RT-PCR.The results showed that on the 21 st day,compared with the 2D cultured epidermal stem cell group and the negative control group,the wounds in the epidermal organ like group completed the epidermization first and formed the skin tissue structure with keratinocyte layer.On the 21 st day,the number of hair follicles and sebaceous glands regenerated at the wound repair in the epidermal organ transplantation group was significantly higher than that in the 2D epidermal stem cell group and the negative control group.On the 21 st day,the m RNA expression levels of hair follicle proliferation related factors HGF and FGF2 in the transplanted epidermal organ like group were significantly higher than those in the 2D epidermal stem cell group and the negative control group.In the experiment of epidermal stem cell and fibroblast migration in vitro,the addition of epidermal organ like conditioned medium group promoted cell migration faster than the addition of 2D cultured epidermal stem cell conditioned medium group and negative control group.In conclusion,the transplantation ofskin organoids can promote the epidermization of the wound and promote the repair of wound accessory organs to a certain extent.