βig-h3-Mediated Adhesion of Fibroblast-Like Synoviocytes in Rheumatoid Arthritis

Abstract

Objective: βig-h3 is an extracellular matrix protein, which is overexpressed in synovial tissues of rheumatoid arthritis (RA) similar to adhesive glycoproteins. We sought to evaluate the compensatory role of βig-h3 with adhesive glycoproteins in mediating the adhesion of fibroblastlike synoviocytes (FLS) and to confirm the inhibitory effect of YH18 peptide of the 2nd fas-1 domain in βig-h3-mediated adhesion.Methods: The adhesion of FLS isolated from synovial tissues of RA, was evaluated in 96 well microtiter plate coated with matrix proteins. Inhibitory effect of YH18 peptides from the 2nd and 4th fas-1 domains was estimated in βig-h3-mediated adhesion of FLS. Results:The adhesion of FLS on βig-h3 was weaker than that of fibronectin and vitronectin.The βig-h3-mediated adhesion was enhanced by the stimulation with phorbol myristate acetate (PMA), but not by cytokines and growth factors. Combination of fibronectin with βig-h3 synergistically enhanced the adhesion of FLS, in contrast to the additive effect of vitronectin combined with βig-h3. YH18 peptide of the 2nd fas-1 domain did not block the βig-h3-mediated