Type II and VI collagen in nasal and articular cartilage and the effect of IL-1alpha on the distribution of these collagens.
The distribution of type II and VI collagen was immunocytochemically investigated in bovine articular and nasal cartilage. Cartilage explants were used either fresh or cultured for up to 4 weeks with or without interleukin 1alpha (IL-1alpha). Sections of the explants were incubated with antibodies for both types of collagen. Microscopic analyses revealed that type II collagen was preferentially localized in the interchondron matrix whereas type VI collagen was primarily found in the direct vicinity of the chondrocytes. Treatment of the sections with hyaluronidase greatly enhanced the signal for both types of collagen. Also in sections of explants cultured with IL-1alpha a higher level of labeling of the collagens was found. This was apparent without any pre-treatment with hyaluronidase. Under the influence of IL-1alpha the area positive for type VI collagen that surrounded the chondrocytes broadened. Although the two collagens in both types of cartilage were distributed similarly, a remarkable difference was the higher degree of staining of type VI collagen in articular cartilage. Concomitantly we noted that digestion of this type of cartilage hardly occurred in the presence of IL-1alpha whereas nasal cartilage was almost completely degraded within 18 days of culture. Since type VI collagen is known to be relatively resistant to proteolysis we speculate that the higher level of type VI collagen in articular cartilage is important in protecting cartilage from digestion.
Jansen
I D C
ID
Department of Periodontology, Academic Center for Dentistry Amsterdam (ACTA), University of Amsterdam and VU University, Research Institute MOVE, Amsterdam, The Netherlands. ineke.jansen@vumc.nl
Hollander
A P
AP
Buttle
D J
DJ
Everts
V
V
D000818:Animals; D002358:Cartilage, Articular / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism*; D002417:Cattle; D024043:Collagen Type II / Q000378:metabolism*; D024142:Collagen Type VI / Q000378:metabolism*; D053582:Interleukin-1alpha / Q000494:pharmacology*; D055171:Nasal Cartilages / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism*; D021381:Protein Transport / Q000187:drug effects; D046509:Tissue Culture Techniques
D024043:Collagen Type II; D024142:Collagen Type VI; D053582:Interleukin-1alpha