FRI0389 Biomarkers as disease activity indicants in patients with systemic lupus erythematosus
Authors: V. Zivkovic, T. Cvetkovic, B. Mitic, B. Stamenkovic, S. Stojanovic, M. Stojanovic, B. Radovanovic Dinic
Journal: Annals of the Rheumatic Diseases (2018)

<h3>Background</h3> In recent years, the search has been going on for the biomarkers potentially useful in the follow-up of patients with systemic lupus erythematosus (SLE). <h3>Objectives</h3> The aim of our study was to establish the importance of various immunological and biological parameters as disease activity indicants in SLE. <h3>Methods</h3> The study involved 85 SLE patients in whom disease activity assessment was performed using the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI). In addition to standard anti-dsDNA antibodies and C3 complement component, anti-nucleosome and anti-C1q antibodies and monocyte chemoattractant protein-1 (MCP-1) were determined in the serum and urine. The antibodies were determined using the ELISA test, while serum and urine MCP1 was determined using the sandwich enzume immunosorbent assay in accordance with the instructions by the manufacturer, R and D Systems, Inc. Minneapolis (USA). <h3>Results</h3> The studied group consisted of 78 women and 7 men, with the mean age of 45.27±9.71 years and average disease duration of 10.37±7.99 years. Univariate linear regression analysis showed that all of the examined parameters with the exception of C3 complement demonstrated a statistically significant impact on the SLEDAI values (for anti-dsDNA p=0.033, anti-nukleosome p=0.002, anti-C1q antibodies p=0.005, serum MCP1 p=0.006, urinary MCP1 p&lt;0.001). The SLEDAI value rose with increasing values of all the parameters except C3 complement. Using the standard multiple regression analysis, the impact of anti-dsDNA, anti-nukleosome, anti-C1q antibodies, complement C3, and serum and urinary MCP1 na SLEDAI was evaluated. The studied model was able to explain 26.60% of disease activity index variance (corrected r<sup>2</sup>=0.246, F=4.755, p&lt;0.001). As the statistically significant risk factors, serum MCP1 (Beta=0.257, p=0.040) and urinary MCP1 (Beta=0.326, p=0.008) could be singled out. Serum MCP1 increased SLEDAI values and explains their variance with 4.80%. The impact of urinary MCP1 was stronger. SLEDAI values increased with elevated urinary MCP1. This parameter was able to explain 8.10% of SLEDAI variance. <h3>Conclusions</h3> The study showed that anti-dsDNA, anti-nukleosome and anti-C1q antibodies were associated with SLE disease activity, but the association was strongest with serum and urinary MCP1. <h3>References</h3> [1] Qin L, Mohan C. Non-invasive biomarkers for systemic lupus erythematosus: A lookback at 2016. Int J Rheum Dis. 2016;19(12):1209–15. [2] Mok CC. Biomarkers for lupus nephritis: a critical appraisal. J Biomed Biotechnol2010;2010:638413. [3] Herbst R, Liu Z, Jallal B, Yao Y. Biomarkers for systemic lupus erythematosus. Int J Rheum Dis. 2012;15(5):433–44. [4] Alharazy S, Kong NC, Mohd M, et al. Urine Monocyte Chemoattractant Protein-1 and Lupus Nephritis Disease Activity: Preliminary Report of a Prospective Longitudinal Study. Autoimmune Dis. 2015;2015:962046. [5] Misra R, Gupta R. Biomarkers in lupus nephritis. Int J Rheum Dis. 2015;18(2):219–32. [6] Gupta R, Yadav A, Aggarwal A. Longitudinal assessment of monocyte chemoattractant protein-1 in lupus nephritis as a biomarker of disease activity. Clin Rheumatol2016;35(11):2707–2714. <h3>Disclosure of Interest</h3> None declared