The role of cytokines in chondrocyte mediated cartilage degradation.
Articular chondrocytes cultured in the presence of recombinant human interleukin 1 alpha (rhIL-1 alpha) or recombinant human tumor necrosis factor alpha (rhTNF alpha) caused increased production of the latent metalloproteinase (collagenase and caseinase) and the proteoglycan release from cartilage. The existences of IL-1 and TNF alpha in the chondrocytes of human articular cartilage were also shown by immunohistochemical staining using polyclonal antibodies. Furthermore, chondrocyte was found to be a producer of interleukin 6 (IL-6), known as a pleiotropic cytokine and thought to be an important mediator of the cell interactions in arthritis. In addition, the production of IL-6 was also shown to be stimulated by rhIL-1 alpha or rhTNF alpha. From our findings, we suggest there exists a very complicated autocrine control system of chondrolysis by the chondrocyte itself.
Shinmei
M
M
Department of Orthopedic Surgery, National Defense Medical College, Tokorozawa, Japan.
Masuda
K
K
Kikuchi
T
T
Shimomura
Y
Y
D000818:Animals; D002358:Cartilage, Articular / Q000166:cytology* / Q000187:drug effects / Q000201:enzymology; D002478:Cells, Cultured; D006801:Humans; D006825:Hybridomas / Q000187:drug effects / Q000201:enzymology*; D007375:Interleukin-1 / Q000378:metabolism / Q000494:pharmacology*; D015850:Interleukin-6 / Q000096:biosynthesis*; D008666:Metalloendopeptidases / Q000096:biosynthesis*; D011509:Proteoglycans / Q000096:biosynthesis*; D011817:Rabbits; D011994:Recombinant Proteins / Q000494:pharmacology*; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism / Q000494:pharmacology*
D007375:Interleukin-1; D015850:Interleukin-6; D011509:Proteoglycans; D011994:Recombinant Proteins; D014409:Tumor Necrosis Factor-alpha; D008666:Metalloendopeptidases