[Association of circulating Treg cells with disease activity in patients with rheumatoid arthritis].
OBJECTIVE
To investigate the changes in the circulating levels of Treg cells in patients with rheumatoid arthritis (RA) and their associations with the disease activity.


METHODS
The fraction of circulating CD4+CD25+FOXP3+ Treg cells in 40 active RA patients and 40 healthy controls were determined by flow cytometry. The serum levels of interleukin-10 (IL-10) and transforming growth factor-β1 (TGF-β1) were measured using enzyme-linked immunosorbent assay, and the expression of Foxp3 mRNA was detected with real-time PCR. The correlation of the changes in the fraction of Treg cells and the disease activity of RA was analyzed.


RESULTS
RA patients showed a significantly lower level of circulating Treg cells than the control subjects [(5.36∓1.55)% vs (7.49∓1.46)%, P<0.01]. The expression of Foxp3 mRNA (P<0.01) and serum IL-10 level (P=0.000) were significantly lower, whereas TGF-β1 significantly higher (P=0.000) in RA patients than in the controls. Spearman analysis showed that serum level of IL-10 but not TGF-β1 was correlated to the fraction of Treg cells and Foxp3 mRNA expression, but the fraction of Treg cells was not correlated to such indices of disease activity as tender joint counts, swollen joint counts, visual analog scale, HAQ, disease activity score in 28 joints, ESR, or CRP, nor to RA self-antibodies (including RF and anti-CCP antibodies).


CONCLUSIONS
A lower fraction and dysfunction of circulating Treg cells might be involved in the pathologies of RA, and a higher disease activity is associated with a greater reduction of Treg cells.
Department of Rheumatology, Southern Medical University, Guangzhou, China. ruilinchen@126.com
Ruilin
R
Chen
Yi
Y
Tao
Kewei
K
Qiu
Wenhui
W
Huang
Chenghui
C
Huang
Juan
J
Li
D000328:Adult; D000368:Aged; D001172:Arthritis, Rheumatoid / Q000097:blood / Q000473:pathology* / Q000503:physiopathology*; D001799:Blood Sedimentation; D018791:CD4 Lymphocyte Count; D016022:Case-Control Studies; D005260:Female; D005434:Flow Cytometry; D051858:Forkhead Transcription Factors / Q000378:metabolism; D006801:Humans; D016753:Interleukin-10 / Q000097:blood; D008297:Male; D008875:Middle Aged; D050378:T-Lymphocytes, Regulatory / Q000166:cytology*; D053773:Transforming Growth Factor beta1 / Q000097:blood
C418974:FOXP3 protein, human; D051858:Forkhead Transcription Factors; C508609:IL10 protein, human; C508960:TGFB1 protein, human; D053773:Transforming Growth Factor beta1; D016753:Interleukin-10