GLIOSTATIN PLATELET-DERIVED ENDOTHELIAL-CELL GROWTH-FACTOR AS A CLINICAL MARKER OF RHEUMATOID-ARTHRITIS AND ITS REGULATION IN FIBROBLAST-LIKE SYNOVIOCYTES/

The objective was to assess the congruity of gliostatin/platelet-deriv ed endothelial cell growth factor (GLS/PD-ECGF) with other clinical ma rkers of rheumatoid arthritis (RA) and to define its molecular mechani sm of action in the complicated cytokine network during RA pathogenesi s. Immunoassay systems were used to quantify GLS or cytokine levels in laboratory and clinical samples. Expression levels of GLS were determ ined by reverse transcription-polymerase chain reaction methods. The G LS levels in synovial fluid were correlated with interleukin-1 (IL-1) and IL-8. The serial data of serum GLS levels reflected well changes i n the disease activity during the clinical course of four representati ve patients with RA, In cultured fibroblast-like synoviocytes, tumour necrosis factor-alpha (TNF-alpha), IL-1, IL-6 and IL-8 induced GLS exp ression. In conclusion, our results suggest that the serum GLS level, mostly derived from cytokine-stimulated synoviocytes, was a useful cli nical marker of RA.