Decrease in 14-3-3η protein levels is correlated with improvement in disease activity in patients with rheumatoid arthritis treated with Tofacitinib.

14-3-3η protein is a proinflammatory mediator that may represent a novel diagnostic and prognostic biomarker for rheumatoid arthritis (RA). We assessed the correlation between changes in serum 14-3-3η levels and changes in clinical disease activity measures in RA patients treated with Tofacitinib (TOF). Paired serum samples from 35 patients with RA were obtained at baseline and 5 months after the initiation of treatment with TOF. The levels of 14-3-3η were measured by JOINT stat 14-3-3η ELISA test kits (Augurex Life Sciences Corp.). The cut-off was defined as 0.19 ng/ml. 14-3-3η positivity was found in 57% of the patients at baseline and in 37% of the patients after 5 months of treatment. Mean ± SD baseline 14-3-3η levels [4.92 ± 8.86 ng/ml] were significantly higher (p < 0.005) than 14-3-3η levels following treatment [1.97 ± 4.59 ng/ml]. A statistically significant improvement (p < 0.001) of CDAI, SDAI, DAS4ESR and DAS4CRP was achieved after 5 month of treatment. Decrease in 14-3-3η protein levels was highly correlated with improvement in DAS4ESR (r = 0.50, p < 0.01), DAS4CRP (r = 0.46, p < 0.01) and ESR (r = 0.36, p = 0.03) and moderately correlated with improvement in CDAI (r = 0.32, p = 0.065) and SDAI (r = 0.33, p = 0.051). The correlation between decrease in 14-3-3η levels and improvement in DAS4ESR remained significant in a partial correlation analysis controlling for ESR (r = 0.39, p = 0.02). This study demonstrates that in RA patients who were treated with TOF, decrease in 14-3-3η levels is correlated with improvement in clinical disease activity parameters. The 14-3-3η protein may serve as an objective biomarker for monitoring of TOF therapy response.

The diagnostic value of 14-3-3η protein levels in patients with rheumatoid arthritis.

14-3-3η may represent a useful diagnostic biomarker for rheumatoid arthritis (RA). We assessed the prevalence and serum levels of 14-3-3η in patients with RA and in patients with other rheumatic diseases. Serum levels of 14-3-3η were measured in 96 patients with RA, in 101 patients with other rheumatic diseases, and in 66 healthy subjects. All of the sera samples were evaluated by JOINT stat 14-3-3η ELISA test kits (Augurex Life Sciences Corp.). Median (IQR) 14-3-3η levels were significantly higher in the early RA group [0.25 ng/ml (0.075-3.11)] and in patients with established RA [0.15 ng/ml (0.08-1.26)] than in healthy subjects [0 ng/ml (0-0)] and disease controls: SLE [0.01 ng/ml (0-0.055)], AS [0.05 ng/ml (0-0.255)], and PsA [0.01 ng/ml (0-0.065)]. The prevalence of 14-3-3η positivity in patients with early RA was 58%, significantly higher than that in disease controls and healthy subjects (p < 0.001). In patients with established RA, this prevalence was 43%, and it was significantly higher than that in patients with other rheumatic diseases and healthy subjects (p < 0.05), excluding the AS group (p = 0.054). In the early RA cohort, the positivity for 14-3-3η, RF, and anti-CCP was 58%, 67%, and 71%, respectively. Eighty-two percent of the patients in this cohort were positive for at least one of these biomarkers. The concentration of 14-3-3η protein may be used to distinguish between patients with early RA and patients with other rheumatic diseases.