TRIM32 DEFICIENCY IS ASSOCIATED WITH INCREASED CARTILAGE DEGRADATION AND ALTERED CHONDROCYTE PHENOTYPE IN HUMAN AND MURINE ARTICULAR TISSUE EX VIVO

TRIM32 is a candidate gene at the 9q33.1 genetic susceptibility locus for hip osteoarthritis (OA). Increased cartilage degradation typical of OA has previously been demonstrated in Trim32 knockout mice.Our aim is to investigate the role of TRIM32 in human and murine articular tissue.TRIM32 expression in human articular cartilage was examined by immunostaining. TRIM32 expression was compared in femoral head chondrocytes from patients with and without primary hip OA (n=6/group) and examined by Western blotting. Aggrecanolysis by femoral head explants from Trim32 knockout (T32KO) and wild-type (WT) mice was compared following stimulation with IL1α or retinoic acid (RA) and was assessed by DMMB assay (n=4/group). Expression of chondrocyte phenotype markers was measured by qPCR and compared between articular chondrocytes from WT and T32KO mice following catabolic (IL1α/TNFα) or anabolic (Oncostatin-M (OSM)/IGF1) stimulation.TRIM32 expression was demonstrated in human articular cartilage; TRIM32 expression by c...