Chondrocyte

These chondrogenic cells differentiate into so-called chondroblasts, which then synthesize the cartilage extracellular matrix (ECM), consisting of a ground substance (proteoglycans, glycosaminoglycans for low osmotic potential) and fibers.

The cell density of full-thickness, human, adult, femoral condyle cartilage is maintained at 14.5 (±3.0) × 103 cells/ mm2 from age 20 to 30 years.

In the deeper zones, chondrocytes form columns that are oriented perpendicular to the cartilage surface, along with the collagen fibers.

The primary cilia are significant for spatial orientation of cells in developing growth plate and are sensory organelles in chondrocytes.

[3] The number of chondrocyte cells created and their maturation process can be influenced by multiple different genes and proteins.

[4] For chondrogenic cells, the treatment showed increased expression of the transcription factor Sox9, which plays a key role in chondrogenesis, the process of cartilage formation from condensed mesenchyme tissues, which then differentiate into chondrocytes.

When the GAG chain functions properly, it controls the maturation speed of chondrocytes and ensures enough cells gather in the cartilage anlage.

One such example, the point mutation G380R located on the fibroblast growth factor receptor 3(FGFR-3) gene leads to achondroplasia, a type of dwarfism.

Individuals with the mutated allele(s) display a variety of symptoms of the failure of endochondral ossification, including the shortening of proximal long limbs and midface hypoplasia.

The non-mutated FGFR-3 gene is responsible for the expression of fibroblast growth factors(FGFs) which has to maintain a certain level to ensure that the proliferation of chondrocytes happens accordingly.

Chondrocytes will proliferate too quickly and disrupt the assembly at the cartilage anlage and detrimentally alter the formation of bone.

[9] In Australia, Ortho-ACI, a suspension of cultured autologous chondrocytes, is indicated for use in the treatment of cartilage lesions associated with the knee, patella, and ankle.