Objectives To detect the differences of T lymphocyte subtypes between healthy controls and axial Spondyloarthritis (SpA), and evaluate whether certain subtypes of T lymphocytes could be an indicator for predicting clinical efficacy before and after TNF-α inhibitor (Infiximab and Etanercept) treatment (for 12 weeks) in active axial SpA patients.
Methods In this study, patients who fulfilled Assessment of Spondyloarthritis international Society (ASAS) criteria for axial SpA had a Bath Ankylosing Spondylitis(BASDAI) of ≥40mm (VAS=100mm). Data including gender, age, disease duration, onset age, family history, HLA-B27, arthritis, hip involvement and CRP were collected. Thirty-five patients received infliximab (5mg/kg) by intravenous injection at weeks 0, 2, 6, 12, and 39 patients received etanercept by hypodermic injection (50mg once a week ) for 12 weeks. At week 12, ASAS20 was used to evaluate the effect of the treatment. At baseline, 6 ml peripheral blood was obtained from patients and healthy controls to detect the percentage of CD3+CD4+, CD3+CD8+, CD3+CD19+, CD3+CD28+ and CD3+CD154+ T-lymphocytess. Nonparametric test was used to analyze the percentage of subtypes of T-lymphocytes between healthy controls and axial SpA patients. ROC curve analysis was conducted to evaluate whether the percentage of above subtypes of T lymphocytes could predict clinical efficacy.
Results Fifty-eight healthy controls and 74 active axial SpA patients were included. Mean age was 26.28±9.08 years and 26.95±8.13 years for healthy controls and axial SpA patients, respectively (P=0.767). In axial SpA patients, 89.19% (n=66) patients were HLA-B27(+), 14.86% (n=11) patients had positive family history, 34.43% (n=24) had arthritis, 12.16% (n=9) had hip involvement. The percentage of CD3+CD19+ T-lymphocytes on peripheral blood T-lymphocytes was significantly higher in axial SpA patients than in healthy controls (13.04±12.99% vs 8.26±2.59%, p=0.013). Analogously, the percentage of CD3+CD154+ T-lymphocytes on peripheral blood T-lymphocytes was significantly higher in axial patients than in healthy controls (1.62±1.89 vs 0.79±0.52, p=0.000). At baseline, the percentage of CD3+CD154+ T-lymphocytes was significantly higher in HLA-B27(+) patients than HLA-B27(-) ones (HLA-B27+ vs HLA-B27-:1.77±1.95 vs 0.41±0.27, P=0.005). In addition, we found that higher percentage of CD3+CD154+ T-lymphocytes was an indicator to predict satisfactory response for clinical efficacy after ROC curve analysis (AUC=0.733, P=0.014)
Conclusions Higher percentage of CD3+CD19+ and CD3+CD154+ T-lymphocytes was detected in active axial SpA patients than healthy controls. In addition, high-percentage of CD3+CD154+ T-lymphocytes was associated with HLA-B27 positive in axial SpA patients. High-percentage of CD3+CD154+ T-lymphocytes may be a predictive factor of clinical efficacy of TNF-α inhibitor treatment in active axial SpA patients.
Lin Q, Lin Z, Gu J, Abnormal high-expression of CD154 on T lymphocytes of ankylosing spondylitis patients is down-regulated by etanercept treatment. Rheumatol Int. 2010;30(3):317-23.
Disclosure of Interest None Declared