Umbilical cord mesenchymal stem cells (19#iSCLife^®) are a kind of pluripotent cells with self-replicating and self-renewal ability. They can differentiate into osteoblast, adipoblast and cartilage with nutrient, immunomodulatory and anti-inflammatory effects. The cytokines promote cell proliferation and synthesis of the matrix, and at the same time, can regulate the microenvironment and activate endogenous progenitor cells through intercellular interaction and secretion of various factors, thereby playing a role in repairing damaged tissues of articular cartilage defects.