Fig. 5

Biomaterials and regeneration of multiple appendages-an ideal skin unit. a, b Traditionally, biomaterials are used as carriers (diverse scales from nano- to macro-, e.g., tubes, rods, wires) to deliver bioactive factors (e.g., drugs, nucleic acid, peptides) or engineered cells (iPSCs) and organoids for tissue repair and regeneration. c In the field of skin wound repair, different combinations of biomaterials and bioactive ingredients have been used to regenerate sweat glands, hair follicles, nerve tissue, and vessel. However, a truly functional artificial skin requires a combination of in vitro and in vivo culture techniques for different cells and tissues. d It is promising to combine these assemblies into an integral construct to form a highly bionic skin unit. Biomaterials due to their variable physical properties can be used to create co-culture scaffolds for skin components, including vessel, nerve, hair follicles, sebaceous glands and sweat glands. In such a bionic skin, suitable conditions are separately established for the survival of various precursor cells (e.g., hair follicular SKPs, Schwann cell precursor, SwGC-like cells) with different regenerative signals to achieve co-culture of multiple skin appendages. Created with BioRender.com. iPSCs induced pluripotent stem cells, SKP skin derived precursor, SwGC sweat gland cell