1.3　Challenges and Perspectives

Skin covers the body surface with unique anatomical structures，and is the first line of defense of the human body.In the future，according to the unique structure of the skin，high-efficiency polymer transdermal drugs can be designed to make up for the shortcomings of traditional treatments and improve curative effects.At the same time，polymer materials are also expected to be used in non-invasive detection and diagnosis of skin diseases.For example，autoimmune diseases are often accompanied by the deposition of immune complexes at the dermal-epidermal junction.If the corresponding polymer materials can be designed according to the structural characteristics of the skin，and then it can replace the skin biopsy，greatly reducing the burden of clinical work.Furthermore，skin immune system plays an important role in the pathogenesis of many skin diseases.In the future，through in-depth research on the functions of various immune cells in different skin diseases，drugencapsulated polymers that specifically target specific subgroups of immune cells can be designed to help precise treatment of skin diseases.Finally，tissue engineered skin has made milestone progress in recent years，which can significantly improve the quality of skin wound repair.In the future，detailed and in-depth research on skin tissue structure can further help us find and design more suitable natural polymer materials for the research and development of tissue engineered skin.In summary，the anatomical structure and function of the skin are the cornerstones of dermatology.Through in-depth exploration of the anatomical structure and function of the skin，the combination of polymer technology and the structure and function of the skin will create the new era of diagnosis and treatment of skin diseases.(https://www.daowen.com)