Efficient gene delivery to articular cartilage using electroporation.

Abstract Effective in vivo gene transfer into articular cartilage has not yet been established. Since chondrocytes are embedded within a rich extracellular matrix, various gene transfer methods have failed to introduce genes into deeper layers of the articular cartilage. In this study, we developed new superfine pointed needle electrodes for in situ electroporation (EP), and investigated the efficiency of gene transfer into articular cartilage with different degrees of degeneration.

Enhanced local production of osteopontin in rheumatoid joints.

Objective: To investigate the involvement of osteopontin (OPN) in the pathogenesis of rheumatoid arthritis (RA), localization and production of OPN were examined in patients with RA.

Methods: Localization of OPN in the rheumatoid synovium was examined by immunohistochemistry. In vitro OPN production by cultured synovial cells from patients with RA (n = 5) and with osteoarthritis (OA) (n = 5) was assessed by ELISA.