Project description:Systemic lupus erythematosus (SLE) is a chronic relapsing autoimmune disease characterized by the production of autoantibodies and multiple organ involvement. In this study, we investigated genome-wide DNA methylation changes in the CD8+ T cells from 8 pairs of lupus patients compared to age, sex, and ethnicity matched healthy controls.
Project description:To screen specific DNA methylation markers in systemic lupus erythematosus (SLE) patient's blood DNA, whole-blood DNAs from 6 female SLE patients and 6 female controls were analyzed by methylation microarray.
Project description:Epigenetic alternations in addition to genetic factors are important contributors to the pathogenesis of Systemic Lupus Erythematosus (SLE). Recent studies revealed that aberrant changes in DNA methylation occur in SLE patients, and potentially contributes to the pathogenesis. Using genome-wide DNA methylation microarray, the Illumina Infinium HumanMethylation450 BeadChip, we compared the DNA methylation level of white blood cells between Chinese female SLE patients with that of healthy controls. There was no difference in global levels of DNA methylation between SLE patients and controls. However, we identified 36 CpG sites with differential loss of DNA methylation and 8 CpG sites with differential gain of DNA methylation, representing 26 genes and 7 genes respectively. Surprisingly, nearly half of the hypomethylated CpG sites were located in the CpG shores, which implicated the functional importance of loss of DNA methylation in the CpG shores in SLE.
Project description:This is the first high-throughput analysis of DNA methylation in autoimmune diseases. We have used a cohort of MZ twins discordant for three diseases whose clinical signs often overlap: systemic lupus erythematosus (SLE), rheumatoid arthritis and dermatomyositis. Only MZ twins discordant for SLE featured widespread changes in the DNA methylation status of a significant number of genes. Individual analysis confirmed the existence of DNA methylation and expression changes in genes relevant to SLE pathogenesis. Our findings not only identify potentially relevant DNA methylation markers for the clinical characterization of SLE patients but also support the notion that epigenetic changes may be critical in the clinical manifestations of autoimmune disease. Total DNA isolated by standard procedures from 59 White Blood Cell (WBC) samples corresponding to monozygotic twins discordant for three different autoimmune diseases: systemic lupus erythematosus (SLE), rheumatoid arthritis (RA) and dermatomyositis (DM) and two additional controls for each MZ twin pair.
Project description:Systemic lupus erythematosus (SLE) is a chronic-relapsing autoimmune disease of incompletely understood etiology. Recent evidence strongly supports an epigenetic contribution to the pathogenesis of lupus. To understand the extent and nature of dysregulated DNA methylation in lupus T cells, we performed a genome-wide DNA methylation study in CD4+ T cells from 12 lupus patients and 12 normal healthy controls. Cytosine methylation was quantified in 27,578 CG pairs located within the promoter regions of 14,495 genes. We identified 236 hypomethylated and 105 hypermethylated CG sites in lupus CD4+ T cells compared to normal controls, consistent with a global hypomethylation in lupus T cells. Further analysis identified hypomethylation in genes involved in connective tissue development including CD9, MMP9, and PDGFRA. Hypermethylated genes highlight “response to nutrients” ontology such as folate biosynthesis, suggesting a link between environmental factor and lupus and emphasizing the role of folate in DNA methylation. In addition, the transcription factor RUNX3 was hypermethylated in lupus CD4+ T cells. Protein-protein interaction maps identified a transcription factor, HNF4a, as a regulatory hub affecting a number of differentially methylated genes. Functional annotations such as apoptosis is also overrepresented. Further, our data indicate that the methylation status of certain genes predicts disease activity in lupus patients. This work provides a foundation to begin identifying novel pathogenic pathways in lupus T cells and developing novel epigenetic biomarkers for disease activity in lupus. We employed microarray-based technologies to perform a genome-wide DNA methylation assay and quantify CD4+ T cell DNA methylation levels at 27,578 CG sites spanning 14,495 genes of 11 lupus patients and 12 healthy controls.