Dr. Julia Oxford
Chondrocytes are cells found in cartilage, and are responsible for the production and secretion of all of the molecules of the extracellular matrix (ECM). Chondrocytes do not survive in the laboratory unless they have been modified in a way that “immortalizes” them. Immortalized chondrocytes serve as a valuable model system in which biomedical research can be carried out without relying on live animal models. Here, we present information on the characterization of the immortalized rat chondrocyte cell line with respect to extracellular matrix production, proliferation rate, optimal culture conditions, the prevelance of apoptotic events, and calcium homeostasis. This work is significant because it will allow us to use this cell line for future studies into the cellular and molecular mechanisms of stress-response of chondrocytes during skeletal development, cancer progression, osteoarthritis, tissue engineering and tissue regeneration. Such studies will depend upon the application of cytochemistry and immunocytochemistry, which are laboratory technique widely used to detect small molecules and proteins within a cultured cell. Antibodies are used to detect the specific proteins via antigen- antibody affinity complex. Fluorescent molecules can be used to visualize the proteins under a microscope. Studies have shown that stress factors on the endoplasmic reticulum such as nutrient depletion, mechanical stress or oxidative stress lead to a decrease in protein expression. Depending on the stress inducer, the cells undergo apoptosis in certain cases. We would like to test how calcium homeostasis is altered and further, how the alteration of calcium homeostasis in chondrocytes affects the expression of collagen II.