Pharmatest offers an in vitro model for studying chondrogenic differentiation and for identifying novel compounds with anabolic effects on chondrogenesis, which is the process of differentiating into cartilage-like cells. The model is based on KS483 multipotent mouse mesenchymal progenitor cells that can be differentiated into chondrocytes, adipocytes and osteoblasts and are a well-characterized model for osteoblast differentiation and bone formation.

The KS483 cells can be used as an in vitro 3D screening platform for testing of potential joint therapies and chondrogenic differentiation or for identifying compounds with inhibitory effects on chondrogenesis. In our assay, the chondrogenic differentiation is performed as pellet cultures where the cells are maintained in high-density pellets to mimic mesenchymal condensation during development. The pellets are embedded in paraffin, sectioned and stained e.g for Safranin O and Alcain blue or processed for immunohistochemistry to visualize type II collagen. For biochemical analysis, the pellets can be digested assayed for sulphated glycosaminoglycan (sGAG) and type II collagen carboxyterminal propeptide (CPII) released into the culture medium. The cells can be easily expanded and utilised for studies including large number of study groups and replicates.

By performing a chondrogenic differentiation assay, researchers can optimize culture conditions for promoting cartilage formation, or evaluate the effects of growth factors or therapeutic agents on chondrogenesis. This assay provides valuable insights into the mechanisms underlying cartilage development and can assist to design tissue engineering strategies for cartilage repair and regeneration.