Association between IL-37 and Systemic Lupus Erythematosus Risk

Area of Science:

• Immunology
• Genetics

Background:

• Interleukin-37 (IL-37) is an anti-inflammatory cytokine with previously observed elevated plasma levels in systemic lupus erythematosus (SLE) patients.
• The relationship between IL-37 levels and clinical manifestations, as well as the association of IL37 gene polymorphisms with SLE risk, remain underexplored.

Purpose of the Study:

• To investigate the correlation between plasma IL-37 levels and clinical laboratory characteristics in SLE patients.
• To examine the association of specific IL37 gene polymorphisms with SLE susceptibility in a Southern Chinese Han population.

Main Methods:

• Plasma IL-37 levels were quantified using enzyme-linked immunosorbent assay (ELISA) in 220 SLE patients and 360 healthy controls.
• Four single-nucleotide polymorphisms (SNPs) in the IL37 gene (rs3811047, rs2723186, rs2723176, and rs4364030) were genotyped.
• Statistical analyses were performed to correlate IL-37 levels with clinical parameters and assess the association of SNPs and haplotypes with SLE risk.

Main Results:

• Plasma IL-37 levels showed a negative association with SLE disease activity index (SLEDAI) and were higher in less active patients.
• Lower IL-37 levels were observed in SLE patients with discoid rash, hypocomplementemia, and proteinuria.
• Significant differences in allele and genotype frequencies for IL37 SNPs rs2723186 and rs4364030 were found between SLE patients and healthy controls.
• Haplotype analysis indicated that the CG haplotype (rs2723176(C) + rs2723186(G)) was more prevalent in SLE patients.

Conclusions:

• Plasma IL-37 levels are linked to SLE disease severity and specific clinical features.
• IL37 gene polymorphisms, specifically rs2723186, rs2723176, and rs4364030, may contribute to SLE susceptibility.