ABSTRACT
objective To study the role of anti-EBV antibody in the development of systemic lupus erythematosus(SLE).Methods Peripheral blood was obtained from 55 SLE patients and 29 normal controls,and anti-EBV-VCA IgG,IgA,IgM antibody was detected by enzyme-linked immunosorbent assay[ELISA).Totat RNA was extracted from peripheral blood of 33 SLE patients and 26 normal controls and then reverse transcribed into complementary DNA.Real-time PCR technique was used to determine gene expressions at the transcription level.Comparison of anti-EBV antibody level and interferon inducible gene expression was made between SLE Datients and normal controls by t-test.The associations between anti-EBV antibody level,lupus activitv and IFN inducible gene expression were analyzed by Spearman's correlation analysis.Results (1)The levels of anti-EBV antibodies in SLE patients were significantly increased as compared to those in the normal controls[IgG(41±6)vs(19±6)U/ml,IgA(15.4±1.8)vs(8.3±2.1)U/ml,IgM(7.8±1.0)vs(3.7±1.2)U/ml]cantly elevated in SLE Datients as compared to normal controls[IFN scores 11±13 vs 0±3](all P0.05).Conclusion Anti-EBV antibody is overproduced in SLE patients but not associated with disease activity as well as the expression level of several major types of I IFN inducible genes,suggesting that EBV infection may not be a major factor mediating the activation of IFN pathway and consequently the exacerbation of SLE.
ABSTRACT
Objective To study the role of the expression levels of 5 type Ⅰ interferon (IFN)-inducible genes (LY6E, OAS1, OASL, MX1, and ISG15) in the diagnosis and disease activity evaluation of systemic lupus erythematosus (SLE). Methods Peripheral blood was obtained from 68 SLE patients, 50 patients with other connective tissue diseases and 26 normal controls, and total RNA was extracted and reverse transcribed into complementary DNA. Real-time PCR technique was used to determine gene expressions at transcription level. An IFN score for each individual was calculated according to the expression of 5 1FN genes. Comparisons of gene expression and IFN score were made among groups. The genes expression levels in patients with SLE were analyzed using receiver operative characteristic curve. The association between IFN scores and disease activity, as assessed by the SLEDAI scores and 24 h proteinuria, was analyzed using Spearman correlation analyses. Results ① The expression levels of MX1, OASL, OAS1, ISG15 and LY6E mRNA in SLE patients were significantly increased as compared with normal controls and disease controls (P all＜0.01 ).② IFN scores in SLE patients (17.9±29.1) were significantly increased as compared with normal controls (0±3.3)and disease controls (3.0±8.1) (P all＜0.01 ). ③ IFN scores area under the ROC curve (AUCROC) was 0.846. When The IFN scores reached 2.56, its sensitivity and specificity for the diagnosis of SLE were 93.1%and 78.3%, respectively. ④ Levels of IFN score was positively correlated with SLEDAI scores (r=0.256,P＜0.05) and 24 h proteinuria (r=0.337, P＜0.05). Conclusion The 5 IFN-inducible genes are highly expressed in SLE patients. IFN score level is valuable for the diagnosis of SLE and a high IFN score is usually associated with an elevated disease activity.
ABSTRACT
Objective To explore the expression levels of interferon-inducible genes in patients with systemic lupus erythematosus ( SLE) , and to validate these gene expressions as potential biomarkers for the differentiation of disease flare and infection.Methods Peripheral blood was obtained from 48 SLE, 16 rheumatoid arthritis ( RA) patients and 26 normal controls, and total RNA was extracted and reverse transcribed into complementary DNA.Real-time PCR technique was used to determine the gene expressions of MX1, OASL,OAS1, ISG15 and LY6E at transcription level.Univariate logistic regression analysis and multivariate conditional logistic regression model were applied to analyze 5 related factors for infection or activity.Results ( 1 ) The expression levels of MX1, OASL, 0AS1, ISG15, and LY6E mRNA in SLE patients were significantly increased as compared with normal controls ( P all < 0.01 ) , while the expression levels of OASL,OAS1 ,ISG15 and LY6E mRNA in SLE patients were also higher than those in RA patients (P all <0.05 ).(2)There were no significant difference between male and female patients of the 5 gene expression in SLE patients.(3) By logistic regression analysis, ISG15 and LY6E were independent risk factors for active SLE patients (P <0.01) , OASL expression was an independent risk factor for SLE patients with infection ( P = 0.003 ).Conclusion All the 5 interferon inducible genes are highly expressed in SLE patients, in which ISG15 and LY6E are independently associated with disease flare, while OASL may be helpful for the evaluation of infection in SLE patients.