IDENTIFICATION OF HUMAN SEMAPHORIN-E GENE-EXPRESSION IN RHEUMATOID SYNOVIAL-CELLS BY MESSENGER-RNA DIFFERENTIAL DISPLAY

Rheumatoid arthritis (RA) is characterised by chronic inflammation of synovial tissue with aggressive proliferation of synovial cells causin g destruction of cartilage and bone. Immunopathological mechanisms, in fectious causes and genetic factors have been discussed, but the etiol ogy of the disease has not been understood until now, Especially, the mechanisms driving tumourlike growth and invasive behaviour of fibrobl astoid synovial cells have not been identified yet. Our aim is to find cellular factors which are mediators for such pathways. One possibili ty to approach this, is searching for disease-relevant genes. We appli ed the mRNA-differential display technique to compare mRNA expression patterns of normal and rheumatic synovial fibroblasts. We identified a n upregulation of the human semaphorin E gene in rheumatoid synovial f ibroblastoid cells. Interestingly semaphorin E is a member of a protei n-family described to play an immunosuppressive role via inhibition cy tokines. A relevance of this finding towards the pathogenesis of RA is discussed. (C) 1997 Academic Press.