Galectin-3 surface expression on human adult chondrocytes: a potential substrate for collagenase-3. Issue 6 (12th May 2004)

• Record Type: Journal Article
• Authors: Guévremont, M; Martel-Pelletier, J; Boileau, C; Liu, F-T; Richard, M; Fernandes, J-C; Pelletier, J-P; Reboul, P
• Is Part Of: Annals of the rheumatic diseases. Volume 63:Issue 6(2004)
• Page Start: 636
• Page End: 643
• Publication Date: 2004-05-12
• Subjects: galectin-3 -- osteoarthritis -- chondrocytes -- collagenase-3 -- integrin-β1; 7-AAD, 7-aminoactinomycin D -- ECM, extracellular matrix -- MMP, matrix metalloproteinase -- OA, osteoarthritis/osteoarthritic -- PBS, phosphate buffered saline -- PCR, polymerase chain reaction -- RT-PCR, reverse transcriptase-polymerase chain reaction -- SDS-PAGE, sodium dodecyl sulphate-polyacrylamide gel electrophoresis; Rheumatism -- Periodicals; 616.723005
• DOI: 10.1136/ard.2003.007229
• Languages: English
• ISSNs: 0003-4967

Abstract

Abstract : Background: Galectin-3 is a lectin detected in mature and early hypertrophic chondrocytes; osteoarthritic (OA) chondrocytes can re-express hypertrophic markers. Objective: To investigate the synthesis and subcellular localisation of galectin-3 in adult chondrocytes as well as the possibility of cleavage of galectin-3 by collagenase-1 and -3. Methods: Galectin-3 was assessed by immunohistochemistry and real time polymerase chain reaction (PCR) in normal and OA cartilage. Its localisation was investigated by subcellular fractionation, immunocytology, and flow cytometry. Proteolysis of galectin-3 by collagenase-1 and -3 was determined by in vitro assay. Results: Galectin-3 expression was increased 2.4-fold as measured by reverse transcriptase (RT)-PCR (p<0.05, n = 5) and threefold by immunohistochemistry (p<0.003 n = 6) in OA cartilage compared with normal cartilage. In adult chondrocytes, galectin-3 was found in the cytosol and membrane enriched fractions. Both immunocytology and flow cytometry confirmed the presence of galectin-3 at the surface of chondrocytes. A strong correlation was found between integrin-β1 and galectin-3 expression at the surface of chondrocytes. Moreover, collagenase-3 cleaved galectin-3 with a higher activity than collagenase-1. The proteolysed sites generated were identical to those produced by gelatinases A and B. Conclusion: Galectin-3 may play a part in OA, having two roles, one intracellular and not yet identified, and another at the cell surface, possibly related to the interaction of chondrocytes and the cartilage matrix.