The G1 domain of aggrecan released from porcine articular cartilage forms stable complexes with hyaluronan/link protein.
OBJECTIVE
To raise peptide antibodies recognizing the C-terminal amino acid sequence in the G1 domain of porcine aggrecan, generated by the action of either aggrecanase or neutral metalloproteinase(s), in rabbits and to use them to investigate the release of aggrecan from porcine articular cartilage.


METHODS
An explant culture system was used to investigate the release of the G1 domain of aggrecan from porcine articular cartilage treated with retinoic acid or interleukin 1beta and to study how the activity of these agents is modified by the proteinase inhibitor, batimastat (BB94).


RESULTS
Retinoic acid and interleukin 1beta induced both enzyme activities and the release of the G1 domain into the culture medium. Proteinase activity was significantly reduced when the tissue was incubated in the presence of BB94. The functional properties of the enzyme-generated G1 domain were studied using large-pore, agarose/polyacrylamide gel electrophoresis, and it was shown to interact with hyaluronan and link protein.


CONCLUSIONS
The results show that there must be a mechanism for removing a functional G1 domain from aggrecan during tissue turnover using this culture system.
Yasumoto
T
T
Molecular Pathology Section, Division of Biomedical Sciences, Imperial College School of Medicine, South Kensington, London SW7 2AZ, UK.
Bird
J L E
JL
Sugimoto
K
K
Mason
R M
RM
Bayliss
M T
MT
D053674:Aggrecans; D000818:Animals; D000918:Antibody Specificity; D002358:Cartilage, Articular / Q000187:drug effects / Q000378:metabolism*; D017077:Culture Media, Conditioned; D046508:Culture Techniques; D010450:Endopeptidases / Q000494:pharmacology; D016326:Extracellular Matrix Proteins; D006025:Glycosaminoglycans / Q000378:metabolism; D006820:Hyaluronic Acid / Q000378:metabolism*; D007106:Immune Sera / Q000276:immunology; D007375:Interleukin-1 / Q000494:pharmacology; D037181:Lectins, C-Type; D008666:Metalloendopeptidases / Q000494:pharmacology; D010446:Peptide Fragments / Q000276:immunology; D010649:Phenylalanine / Q000031:analogs & derivatives* / Q000494:pharmacology; D011480:Protease Inhibitors / Q000494:pharmacology; D011509:Proteoglycans / Q000276:immunology / Q000378:metabolism*; D011817:Rabbits; D013552:Swine; D013876:Thiophenes / Q000494:pharmacology; D014212:Tretinoin / Q000494:pharmacology
D053674:Aggrecans; D017077:Culture Media, Conditioned; D016326:Extracellular Matrix Proteins; D006025:Glycosaminoglycans; D007106:Immune Sera; D007375:Interleukin-1; D037181:Lectins, C-Type; D010446:Peptide Fragments; D011480:Protease Inhibitors; D011509:Proteoglycans; D013876:Thiophenes; D010649:Phenylalanine; D014212:Tretinoin; D006820:Hyaluronic Acid; C080985:batimastat; D010450:Endopeptidases; D008666:Metalloendopeptidases; C083641:aggrecanase