系统性红斑狼疮患者EB病毒感染状态与I型干扰素及干扰素诱导基因的相关性研究

The relationship between Epstein-Barr virus infection status, interferona level and type I interferon induced genes in patients with systemic lupus erythematosus

目的观察EB病毒抗体、IFN—α以及多个I型IFN诱导基因在SLE患者和健康对照体内的表达，分析EB病毒不同感染状态与I型IFN通路之间的关系及其与SLE的相关性。方法共入选48例SLE患者和36名健康对照者。双抗体夹心法检测研究对象血清EB病毒衣壳抗原-IgG、IgM抗体和EB病毒核抗原1—IgG抗体阳性率及IFN—α浓度；实时荧光定量PCR检测研究对象外周血淋巴细胞各IFN诱导基因2′-5′寡腺甘酸样合成酶（OASL）、黏液病毒抗性蛋白（MX）1、IFN刺激基因（ISG）15和淋巴细胞抗原6复合体E（LY6E）mRNA表达水平（以2^-△△Ct,值作为基因表达水平的指标）。统计分析采用t检验或Mann-Whitney U检验（方差不齐时）、χ^2检验及Spearman相关分析。结果①SLE患者中EB病毒增殖感染阳性率高于健康对照（40％和11％，χ^2=5．381，P=-0．027）。②SLE患者血清IFN—α浓度高于健康对照I（206±151）ng／L与（90±76）ng／L，t=4．248，P〈0．05]；OASL、MX1、ISG15和IJY6E mRNA的表达均高于健康对照组[分别为1．8（0．6，5．1）与1．2（0．5，1．4）；1．9（1．0，4．4）与0．9（0．7，2．5）；4．1（1．6，7．8）与0．8（0．5，1．7）；1．6（0．7，3.3）与0．8（0．6，1．2），U值分别为604，560，312，608，均为P〈0．05]；OASL、MX1、ISG15以及LY6E表达水平与SLEDAI均呈正相关（r=0．319，0．461，0．547，0．484，均为P〈0．05）。③EB病毒增殖感染的SLE患者血清IFN-α水平高于非增殖感染患者[（282±174）ng／L与（157±114）ng／L，t=2．604，P〈0．05]；EB病毒增殖感染的SLE患者IFN诱导基因OASL和ISGl5mRNA的表达高于非增殖患者[分别为2．0（0．8，7．6）与1．2（0．6，3．1）；6．2（2．4，15．5）与3.3（1.3，6．3），U值分别为377，350，385，354，均为P〈0．05]；EB病毒增殖感染的SLE患者，其SLEDAI分值高于非增殖感染者（16±4与12±8，P〈0．05）。结论EB病毒感染可能通过激活I型IFN通路参与了SLE的发病及病情进展。

Objective To explore whether different Epstein-Barr virus （EBV） infection status is involved in systemic lupus erythematosus （SLE） patbogenesis 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/IgM 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%,χ^2=5.381, P=-0.027）. ②The 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）. ③ Serum IFN-α levels were elevated in SLE patients with EBV lytic infection than in non-lyric 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 lyric 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 lytic 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.