Proteoglycan Production by Immortalized Human Chondrocyte Cell Lines Cultured under Conditions That Promote Expression of the Differentiated Phenotype

Up‐regulation of microsomal prostaglandin E synthase 1 in osteoarthritic human cartilage: Critical roles of the ERK‐1/2 and p38 signaling pathways

“…Since only limited amounts of human tissue were available, we used the immortalized chondrocyte cell line T/C-28a2, which retains the characteristics of chondrocytes and provides enough cells for extensive studies (24,25,35). We used Northern blotting Figure 2B).…”

“…This cell line retains some of the specific phenotype of chondrocytes in long-term culture and is thus a suitable model for reproducible studies of chondrocyte metabolism (24)(25)(26). In chondrocytes, IL-1␤ and tumor necrosis factor rapidly activated the various members of the MAPK family, including ERK, JNK, and p38 MAPK (27)(28)(29).…”

Shear-induced Cyclooxygenase-2 via a JNK2/c-Jun-dependent Pathway Regulates Prostaglandin Receptor Expression in Chondrocytic Cells

“…Cell Culture-The human T/C-28a2 chondrocytic cell line (21)(22)(23) was chosen as a model system for monitoring chondrocytic cellular responses to fluid shear for three important reasons. First, the T/C28a2 cells have been extensively characterized and shown to behave much like primary human chondrocytes when cultured under appropriate conditions (21)(22)(23).…”

“…First, the T/C28a2 cells have been extensively characterized and shown to behave much like primary human chondrocytes when cultured under appropriate conditions (21)(22)(23). Second, a sufficient number of primary human chondrocytic cells to perform microarray and ribonuclease protection assay (RPA) experiments are difficult to obtain from a single operative procedure, whereas the chondrocytic phenotype is gradually lost in primary cultures over serial passaging.…”

“…Before shearing experiments, T/C-28a2 cells were detached from tissue culture flasks by mild trypsinization, then seeded (1 ϫ 10 6 cells/ml) on 75 ϫ 38-mm glass slides (Corning Glass) and incubated overnight at 37°C in 10% fetal bovine serum-containing medium. 24 h before shear stress exposure, T/C-28a2 cells were washed with Dulbecco's phosphate-buffered saline lacking Ca 2ϩ /Mg 2ϩ (DPBS), and incubated in serum-free medium composed of 1:1 Ham's F-12 and Dulbecco's modified Eagle's media, supplemented with 1ϫ antibiotic-antimycotic and 1% Nutridoma SP (Roche Molecular Biochemicals) to maintain chondrocytic phenotype (23). Throughout cell culturing and shearing experiments, the T/C-28a2 cells maintained their polygonal morphology and failed to exhibit Type I collagen expression, both of which are congruent with the chondrocyte phenotype (21).…”