T-cell DNA hypomethylation can increase expression of genes that have potential relation to autoimmunity. CD70 overexpression may be associated with B-cell activation and immunoglobulin secretion, while perforin plays an important role in T-cell-mediated macrophage apoptosis. DNA hypomethylation can activate human endogenous retroviruses (HERV) sequences. Expression of HERV components may elicit autoantibodies production. Polyamines change structure of chromosome and interfere with DNA methylation process, which is involved in the pathogenesis of autoimmune diseases.
DNA Methylation ; Humans ; Lupus Erythematosus, Systemic ; etiology ; genetics ; immunology

The expression of inducible co-stimulator (ICOS) in peripheral blood T lymphocytes from the patients with systemic lupus erythematosus (SLE) and the role in the pathogenesis of SLE was investigated. By using two-color immunofluorescent staining and flow cytometric assay, the expression levels of ICOS in peripheal blood T lymphocytes from 33 patients with SLE and 16 healthy volunteers were detected. SLE diseases activity index (SLEDAI) of the patients with SLE was used to evaluate the disease activity. The correlation between the ICOS expression and SLEDAI was analyzed among the groups. The results showed that the expression levels of ICOS in T lymphocytes in active SLE group was markedly higher than those in the control and inactive SLE groups (both P< 0.01). There was no significant difference in the expression levels of ICOS between the inactive SLE and the control groups (P>0.05). In active SLE and inactive SLE groups, positive linear correlation was found between the levels of the ICOS expression in T lymphocytes and SLEDAI (r=0. 711, P=0.001; r=0.561, P=0.03). It was suggested that the expression of ICOS in peripheral blood T lymphocytes from the patients with active SLE was up-regulated and and ICOS might be related to the pathogenesis of SLE.
Antigens, Differentiation, T-Lymphocyte/*biosynthesis ; Antigens, Differentiation, T-Lymphocyte/genetics ; Lupus Erythematosus, Systemic/blood ; Lupus Erythematosus, Systemic/etiology ; Lupus Erythematosus, Systemic/*immunology ; T-Lymphocytes/*immunology

Exosomes are nanometer-sized membranous extracellular vesicles that can be secreted by almost all types of cells in the body. Exosomes are involved in cell-to-cell communication through autocrine and paracrine forms. Exosomal microRNAs (miRNAs) are stable in plasma, urine and other body fluids, and have various biological functions. They play an irreplaceable role in the occurrence, development, immune regulation of systemic lupus erythematosus (SLE). Recent studies have proposed that exosomal miRNAs have promising application prospects in the pathogenesis, early diagnosis, and treatment of SLE. Therefore, this review aims to introduce the current research progress on exosomal miRNAs in SLE and analyze their potential application value.
Cell Communication ; Exosomes/genetics* ; Humans ; Lupus Erythematosus, Systemic/genetics* ; MicroRNAs/genetics*

BACKGROUND: Systemic lupus erythematosus (SLE) is a complex autoimmune disease, and the mechanism of SLE is yet to be fully elucidated. The aim of this study was to explore the role of two-pore segment channel 2 (TPCN2) in SLE pathogenesis. METHODS: Quantitative reverse transcription polymerase chain reaction (qRT-PCR) was used to detect the expression of TPCN2 in SLE. We performed a loss-of-function assay by lentiviral construct in Jurkat and THP-1 cell. Knockdown of TPCN2 were confirmed at the RNA level by qRT-PCR and protein level by Western blotting. Cell Count Kit-8 and flow cytometry were used to analyze the cell proliferation, apoptosis, and cell cycle of TPCN2-deficient cells. In addition, gene expression profile of TPCN2-deficient cells was analyzed by RNA sequencing (RNA-seq). RESULTS: TPCN2 knockdown with short hairpin RNA (shRNA)-mediated lentiviruses inhibited cell proliferation, and induced apoptosis and cell-cycle arrest of G2/M phase in both Jurkat and THP-1 cells. We analyzed the transcriptome of knockdown-TPCN2-Jurkat cells, and screened the differential genes, which were enriched for the G2/M checkpoint, complement, and interleukin-6-Janus kinase-signal transducer and activator of transcription pathways, as well as changes in levels of forkhead box O, phosphatidylinositol 3-kinase/protein kinase B/mechanistic target of rapamycin, and T cell receptor pathways; moreover, TPCN2 significantly influenced cellular processes and biological regulation. CONCLUSION TPCN2 might be a potential protective factor against SLE.
Apoptosis/genetics* ; Cell Division ; Humans ; Jurkat Cells ; Lupus Erythematosus, Systemic/genetics* ; RNA, Small Interfering/genetics*

Autoimmune-related skin diseases are a group of disorders with diverse etiology and pathophysiology involved in autoimmunity. Genetics and environmental factors may contribute to the development of these autoimmune disorders. Although the etiology and pathogenesis of these disorders are poorly understood, environmental variables that induce aberrant epigenetic regulations may provide some insights. Epigenetics is the study of heritable mechanisms that regulate gene expression without changing DNA sequences. The most important epigenetic mechanisms are DNA methylation, histone modification, and noncoding RNAs. In this review, we discuss the most recent findings regarding the function of epigenetic mechanisms in autoimmune-related skin disorders, including systemic lupus erythematosus, bullous skin diseases, psoriasis, and systemic sclerosis. These findings will expand our understanding and highlight the possible clinical applications of precision epigenetics approaches.
Humans ; Autoimmune Diseases/genetics* ; Epigenesis, Genetic ; Lupus Erythematosus, Systemic/genetics* ; DNA Methylation ; Psoriasis/genetics*

Systemic lupus erythematosus (SLE) is the prototype systemic autoimmune disease and genetic component seems to play an important role in disease susceptibility. Studies from murine models have shown that about 30 loci are related to the disease. Meanwhile, 50 loci have been found in linkage to SLE in human genomic studies, especially 1q23-24, 1q41-42, 2q37, 4p16-15.2, 6p21-11 and 16q13. A lot of candidate genes contribute to the disease susceptibility and different combinations of genes at multiple loci in individual patient may result in the development of diverse clinical features.
Animals ; Chromosome Mapping ; Genetic Predisposition to Disease ; genetics ; Humans ; Lupus Erythematosus, Systemic ; genetics ; Research ; trends

This study examined the gene expression patterns of peripheral blood mononuclear cells (PBMCs) in patients with systemic lupus erythematosus (SLE) by using serial analysis of gene expression (SAGE) technology. Following the construction of serial analysis of gene expression (SAGE) library of PBMCs collected from 3 cases of familial SLE patients, a large scale of tag sequencing was performed. The data extracted from sequencing files was analyzed with SAGE 2000 V 4.5 software. The top 30 expressed genes of SLE patients were uploaded to http://david.niaid.nih.gov/david/ease.htm and the functional classification of genes was obtained. The differences among those expressed gene were analyzed by Chi-square tests. The results showed that a total of 1286 unique SAGE tags were identified from 1814 individual SAGE tags. Among the 1286 unique tags, 86.8% had single copy, and only 0.2% tags had more than 20 copies. And 68.4% of the tags matched known expressed sequences, 41.1% of which matched more than one known expressed sequence. About 31.6% of the tags had no match and could represent potentially novel genes. Approximately one third of the top 30 genes were ribosomal protein, and the rest were genes related to metabolism or with unknown functions. Eight tags were found to express differentially in SAGE library of SLE patients. This study draws a profile of gene expression patterns of PBMCs in patients with SLE. Comparison of SAGE database from PBMCs between normal individuals and SLE patients will help us to better understand the pathogenesis of SLE.
Expressed Sequence Tags ; Gene Expression Profiling/*methods ; Leukocytes, Mononuclear/*metabolism ; Lupus Erythematosus, Systemic/blood ; Lupus Erythematosus, Systemic/*genetics ; Sequence Tagged Sites ; Transcription, Genetic

OBJECTIVES: Systemic lupus erythematosus (SLE) is a kind of autoimmune inflammatory connective tissue disease which seriously endangers human health. Genetic factors play a key role in the pathogenesis of SLE. This study aims to investigate a novel phospholipase D2 (PLD2) mutation associated with familial SLE, and further explore the underlying mechanism of the mutation in SLE. METHODS: The blood samples from a SLE patient, the patient's parents, and 147 normal controls were collected and DNA was extracted. Whole genome high-throughput sequencing was performed in the patient and her parents and the results were further analyzed by various bioinformatics methods. The wild type (wt), mutant type (mu), and negative control PLD2 plasmids were further constructed and transfected into 293 cells. The expression level of HRAS protein in 293 cells was detected by Western blotting. RESULTS: In this SLE family, the female SLE patient and her mother, 1 in generation II and 1 in generation III had typical clinical manifestations of SLE, and all of them had lupus nephritis at early stage. The genetic characteristics are consistent with autosomal dominant inheritance. A novel PLD2 heterozygous mutation (c.2722C>T) was found in the patient and her mother, but not in her father and other normal controls. Compared with wtPLD2 plasmid and negative control PLD2 plasmid, the expression of HRAS in 293 cells transfected with muPLD2 plasmid was significantly up-regulated (both CONCLUSIONS PLD2 c.2722C>T mutation may be one of the pathogeny of SLE in this family.
Case-Control Studies ; Female ; High-Throughput Nucleotide Sequencing ; Humans ; Lupus Erythematosus, Systemic/genetics* ; Lupus Nephritis ; Mutation ; Phospholipase D

Adult ; Female ; Humans ; Hypertension, Pulmonary ; genetics ; Lupus Erythematosus, Systemic ; genetics ; Male ; Nerve Tissue Proteins ; genetics ; Polymorphism, Single Nucleotide

OBJECTIVETo detect the methylation status of p16 gene promotor in DNA derived from plasma and blood cells of patients with systemic lupus erythematosus (SLE) , and it's relationship with clinical symptoms.

METHODSp16 promotor methylation in plasma and peripheral blood cells (PBCs) DNA were simultaneously detected with the methylation specific PCR (MSP) method in 24 active SLE patients, 21 inactive SLE patients, as well as 20 healthy controls.

RESULTSIn the plasma DNA, p16 gene methylation ratio (MP%) was higher in SLE patients than in the healthy controls (64.4% vs. 5.0%, P < 0.05). MP% in the active SLE patients was significantly higher than that in the inactive SLE patients (83.3% vs. 42.9%, P < 0.05). In the PBCs, p16 gene methylation ratio (MC%) in the healthy controls was significantly higher than that in SLE (80.0% vs. 48.9%, P < 0.05). MC% in the active SLE patients (29.2%) was the lowest among three groups. There was no significant difference between the inactive SLE patients and healthy controls (71.4% vs. 80.0%, P > 0.05). Each patient could be judged as one of the four methylation patterns: MP/MC, UP/MC (UP: unmethylated plasma p16) , MP/UC (UC: unmethylated PBCs p16) , and UP/UC. The ratios of MP/ MC and UP/UC were similar between the active and inactive SLE patients. However, different distributions of other two patterns were found in the active and inactive SLE patients as UP/MC 4.2% vs. 42.9% (P <0.05) and MP/UC 58.3% vs. 14.3% (P < 0.05), respectively. The active SLE patients with MP/UC and the inactive SLE patients with UP/MC showed different clinical symptoms and laboratory examinations. Significant correlation was found between the disease activity index for lupus patients (SLEDAI) scores and MP% (r = 0.93), between the SLEDAI scores and MC% (r = - 0.96) also between MC% and MP% (r = - 0.79).

CONCLUSIONThe p16 methylation assay provides available information for the diagnosis, judgment of disease activity, as well as novel insights into the pathogenesis underlying this disease.

Adult ; DNA Methylation ; Female ; Genes, p16 ; Humans ; Lupus Erythematosus, Systemic ; diagnosis ; genetics ; Male ; Polymerase Chain Reaction ; Promoter Regions, Genetic ; genetics