At the destination, the cells act as follows
Some of the cells actually become cartilage tissue, and it has been proven several times by various authors that the cartilage increases in volume and the hyaline portions increase, not just the fibrocartilage portions.
Another important effect is the release of vesicles/secretomes, which are messenger substances that the stem cells send to the target cells at the request of the target tissue, sometimes also by forming special transmission structures (tubules).
The third effect is a healing effect on the target tissue, with an upregulation of cartilage-protecting messenger substances (proteins) and a reduction of pro-inflammatory interleukins (proteins). This can be detected and quantified based on the activated genes in the target cells (cartilage and synovial membrane).
A recently described effect is that via EVs (extracellular vesicles), which are substances that are packaged in cell membranes and diffuse between cells in the so-called "third space" to the damaged tissue.