Chondrocyte: located in the cartilage lacuna. The naive chondrocytes are located on the surface of the cartilage tissue. They are single-distributed, small in size, and elliptical. The long axis is parallel to the cartilage surface. The deeper the chondrocyte volume increases in a round shape, and the nucleus is round or oval. , staining shallow, cytoplasmic weak basophilic, a common number of lipid droplets. Mature chondrocytes are distributed in 2 to 8 groups in the cartilage lacuna. These chondrocytes are proliferated by the same mother cell and are called homologous cell populations. Under electron microscopy, the chondrocytes have protrusions and wrinkles, and the cytoplasm has a large number of rough endoplasmic reticulum and a developed Golgi complex and a small amount of mitochondria. In tissue sections, chondrocytes contract to an irregular shape with large cavities between the cartilage sac and the cells. Autologous chondrocytes were purified and amplified by GTP laboratory experts and transplanted to the site of articular cartilage defects. These high-quality artificially cultivated chondrocytes quickly help the joints to repair, which can promote the growth of new healthy cartilage without showing side effects.