Serum soluble toll-like receptor 2: a novel biomarker for systemic lupus erythematosus disease activity and lupus-related cardiovascular dysfunction

Aim: To assess the serum levels of soluble toll-like receptor (sTLR2) as an endogenous negative regulator of TLR2 signaling in systemic lupus erythematosus (SLE) patients, to investigate the correlation between sTLR2 and SLE disease activity index (SELDAI), SLE-related cardiovascular risk factors and ventricular dysfunction and to evaluate the effect of different therapeutic regimens on serum sTLR2 levels. Methods: Ninety-six SLE patients, along with 30 healthy controls, were enrolled in the study. Echocardiography measurements were performed. Serum levels of (sTLR2) were measured using enzyme-linked immunosorbent assay (ELISA). Serum lipid profiles, uric acid and creatinine were also detected. Results: Mean serum levels of sTLR2 in SLE patients was 3.98 ± 4.4 ng/mL, which was significantly decreased as compared with that of the control group (11.3 ± 4.9 ng/mL; P < 0.0001). sTLR2 was negatively correlated with SELDAI, low-density lipoprotein (LDL) and left ventricular diastolic dysfunction. sTLR2 levels were increased in patients receiving hydroxychloroquine, statins and corticosteroids. Conclusion: Serum sTLR2 can attenuate disease activity and negatively impact left ventricular diastolic dysfunction and hypercholersterelemia in SLE patients. Statins, corticosteroids and chloroquine increase sTLR2 levels.