The relationship between Epstein-Barr virus infection status, interferon α level and type Ⅰ interferon induced genes in patients with systemic lupus erythematosus / 中华风湿病学杂志

ABSTRACT

Objective To explore whether different Epstein-Barr virus (EBV) infection status is involved in systemic lupus erythematosus (SLE) pathogenesis through type Ⅰ interferon pathway by observing the EBV antibodies,serum interferon α (IFN-α) level and four type Ⅰ interferon induced gene (ISGs;2'-5' oligoadenylate synthetase-like protein (OASL),myxovirous resistant 1 (MX1),interferon-stimulated gene 15 (ISG15) and lymphocyte antigen 6 complex,locus E (LY6E) expressions in SLE patients and healthy controls.Methods Forty-eight patients with SLE and 36 healthy controls were enrolled into this study.The serum antibodies of EBV capsid antigen-IgG/lgM and EBV nuclear antigen 1-IgG,and serum levels of IFN-α were measured by enzyme linked immunosorbent assay (ELISA) method.Real time reverse transcription polymerase chain reaction was used to test the mRNA levels of OASL,MX1,ISG15 and LY6E in the peripheral blood lymphocytes (2-△△Ct was used to indicate the gene expression).Statistical analysis was performed using t-test or Mann-Whitney U test,Chi square test and Spearman correlation test.Results ① The EBV lytic infection rate (VCA-IgM) in SLE patients was higher than that in healthy controls (40％ vs 11％,x2=5.381,P=0.027).② The serum levels of IFN-α in SLE patients were higher than those in the healthy controls [(206±151) ng/L vs (90± 76) ng/L,t=4.248,P＜0.05],as well as the mRNA levels of OASL,MX1,ISG15 and LY6E [1.8(0.6,5.1) vs 1.2 (0.5,1.4);1.9(1.0,4.4) vs 0.9(0.7,2.5);4.1(1.6,7.8) vs 0.8(0.5,1.7);1.6(0.7,3.3) vs 0.8(0.6,1.2),U=604,560,312,608;P＜0.05,respectively].The mRNA levels of OASL,MX1,LY6E and ISG15 were all positively related to SLE disease activity index (SLEDAI) scores (r=0.319,0.461,0.547,0.484,P＜0.05,respectively).Serum IFN-α levels were elevated in SLE patients with EBV lytic infection than in non-lytic infection patients [(282± 174) ng/L vs (157±114) ng/L,t=2.604,P＜0.05];The mRNA levels of OASL and ISG15 were also elevated in patients with lytic EBV infection [2.0(0.8,7.6) vs 1.2(0.6,3.1);6.2(2.4,15.5) vs 3.3(1.3,6.3),U=377,350,385,354;P＜0.05,respectively].The SLEDAI scores in patients with EBV lyric infection were higher than in patients with non-lyric infection (16±4 vs 12±8,P＜0.05).Conclusion EBV infection may be involved in the pathogenesis of SLE by activating the type Ⅰ interferon pathway.