title: Stress-induced proteins in chondrocytes from patients with osteoarthritis.
abstract: Recent studies have shown that a specific set of proteins is produced by a variety of cells after the application of some forms of stress, including heat shock. Human chondrocytes isolated from cartilage with moderate to severe osteoarthritis synthesize at least 1 of these stress proteins (Mr 70,000) at physiologic temperature (37 degrees C), whereas chondrocytes isolated from non-pathologic cartilage synthesize this protein only in response to incubation at temperatures above 39 degrees C. The active synthesis of this protein (SP-70) at 37 degrees C is positively correlated with the severity of osteoarthritis and can be a characteristic indicator of this degenerative disease. We identified the active synthesis of stress proteins after incubating the cartilage tissue in medium containing 35S-methionine and separating the cell-associated proteins by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The radioactive proteins were visualized by autoradiography. Analysis of the longevity of cell-associated proteins was determined by pulsing the tissue with 35S-methionine, and after different periods of chase in medium, the proteins were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Specific proteins bands were then excised, and the radioactivity was determined by liquid scintillation counting.
mesh_terms: D001345:Autoradiography; D002358:Cartilage, Articular / Q000378:metabolism* / Q000473:pathology; D004586:Electrophoresis; D006207:Half-Life; D006360:Heat-Shock Proteins / Q000378:metabolism*; D006801:Humans; D010003:Osteoarthritis / Q000378:metabolism*; D012016:Reference Values
chemical_list: D006360:Heat-Shock Proteins