Increased TTS expression in patients with rheumatoid arthritis.

Immune system activation is known to be involved in the progression of rheumatoid arthritis (RA). The aim of this work was to study the imbalance expressions of indoleamine 2,3-dioxygenase (IDO) and tryptophanyl-tRNA synthetase (TTS) with RA patients. Forty-nine RA patients and 49 healthy controls were studied. The expressions of IDO and TTS were analyzed by real-time quantitative polymerase chain reaction and flow cytometry in peripheral blood mononuclear cells. The expression of TTS mRNA increased significantly in RA patients when compared with healthy controls and correlated with erythrocyte sedimentation rate (r = 0.424, P < 0.01). In addition, we found TTS increased significantly mainly in CD3(+) T cells in rheumatoid arthritis group. Increased TTS expressions from CD3(+) T cells might link to a pathogenic mechanism involved in increasing survival of autoreactive T cells in RA patients. Determination of expressions of TTS may provide a better understanding of progression of the disease.