Exosome and application thereof in treatment of osteoarthritis

The invention relates to an exosome. The exosome is an exosome derived from stem cells. The stem cells are human umbilical cord mesenchymal stem cells which are subjected to genetic engineering pretreatment and over-express SOX9 genes. The exosome is obtained by collecting exosomes derived from overexpressed SOX9 umbilical cord mesenchymal stem cells. The exosome is an exosome from an overexpression SOX9 umbilical cord mesenchymal stem cell source. The exosome of the umbilical cord mesenchymal stem cell derived from the high-expression SOX9 gene is prepared for the first time, and compared with an exosome of a common umbilical cord mesenchymal stem cell, the exosome obviously promotes autophagy of damaged cartilage cells, inhibits catabolism of an extracellular matrix of cartilage, promotes anabolism of the extracellular matrix of cartilage, and improves the survival rate of cartilage cells. Therefore, the metabolic balance of the cartilage extracellular matrix is maintained, and the method is very suitable f