High frequency of concurrent anti-C1q and anti-dsDNA but not anti-C3b antibodies in patients with Lupus Nephritis

ABSTRACT

Lupus Nephritis (LN) in patients with Systemic Lupus Erythematosus (SLE) is one of the most serious and prevalent manifestations. The procedure of renal biopsy is harmful and accompanied by potential hazards. Therefore, introducing reliable biomarkers to predict LN is exceedingly worthwhile. In the present study, we compared the diagnostic values of circulating autoantibodies against dsDNA, C1q, C3b, SSA, SSB, and Sm alone or in combination to predict LN. This study evaluated the abovementioned autoantibodies in 40 healthy controls (HCs) and 95 SLE patients with different kidney involvements, including absent (n = 40), inactive (n = 20), and active (n = 35) LN using EIA method. The frequency and odds ratio of anti-dsDNA (71.4%, OR = 4.2), anti-C1q (62.9%, OR = 5.1), and the simultaneous existence of anti-C1q and anti-dsDNA (51.4%, OR = 6) antibodies were significantly higher in the active LN group compared with both inactive and absent LN groups. Moreover, the levels of anti-C1q and anti-dsDNA antibodies positively correlated with disease activity in patients with SLE. The prevalence of these autoantibodies was associated with the severity of LN biopsies. These data suggest that anti-C1q and anti-dsDNA antibodies and also their simultaneous presence may be valuable diagnostic biomarkers for LN prediction in patients with SLE.

KEYWORDS:

• Lupus Nephritis
• anti-C1q antibody
• anti-dsDNA antibody
• anti-C3b antibody
• biomarkers
• systemic Lupus Erythematosus

The key messages (highlights) of this study including

Limited studies have been performed to evaluate the simultaneous presence of anti-complements and other pathogen antibodies and also their association with lupus nephritis severity in patients with SLE disease with different kidney involvements. In this study, in addition to healthy control, patients with no history of nephritis were compared with SLE patients with active and inactive nephritis. Finally, the results emphasized the importance of simultaneous screening of anti-C1q and anti-dsDNA antibodies in patients with SLE to predict nephritis.

Disclosure statement

The authors stated there was no conflict of interest.

Additional information

Funding

This research was supported by Iran University of Medical Sciences (Code:IR 94-03-30-26574). This manuscript has been previously posted in a preprint format in ScholarOne (DOI: https://doi.org/10.21203/rs.3.rs-34346/v1).^[42]