Increased expression of IL-28RA mRNA in peripheral blood mononuclear cells from patients with systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a systemic autoimmune and inflammatory disease with a strong genetic contribution and characterized by kinds of immune reactions. Our previous genome-wide association studies have identified IL-28RA as a susceptibility gene for SLE. In this study, we performed a quantitative reverse transcription polymerase chain reaction (RT-PCR) in 62 patients with SLE and 69 controls to investigate the different expression levels of IL-28RA in peripheral blood mononuclear cells (PBMCs) from SLE patients and healthy controls and the association between IL-28RA expression and systemic lupus erythematosus disease activity index (SLEDAI) or the variant of the single-nucleotide polymorphism (SNP) rs4649203. The expression levels of IL-28RA messenger RNA (mRNA) in SLE patients were significantly increased compared with those of healthy controls. In addition, there were also significant differences in the expression levels of IL-28RA between active (SLEDAI ≥ 6) or inactive (SLEDAI < 6) SLE groups and healthy controls. However, no correlation was observed between IL-28RA mRNA expression level and SLEDAI. There was no association between the variant of the SNP rs4649203 and IL-28RA mRNA expression levels neither. These results indicated that expression of IL-28RA mRNA may be correlated with the pathogenesis of SLE.