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Review

Epigenetic Dysregulation in the Pathogenesis of Systemic Lupus Erythematosus

Department of Rheumatology and Applied Immunology, Faculty of Medicine, Saitama Medical University, Saitama 350-0495, Japan
*
Author to whom correspondence should be addressed.
Int. J. Mol. Sci. 2024, 25(2), 1019; https://doi.org/10.3390/ijms25021019
Submission received: 7 November 2023 / Revised: 5 January 2024 / Accepted: 11 January 2024 / Published: 13 January 2024

Abstract

:
Systemic lupus erythematosus (SLE) is a multisystem autoimmune disease in which immune disorders lead to autoreactive immune responses and cause inflammation and tissue damage. Genetic and environmental factors have been shown to trigger SLE. Recent evidence has also demonstrated that epigenetic factors contribute to the pathogenesis of SLE. Epigenetic mechanisms play an important role in modulating the chromatin structure and regulating gene transcription. Dysregulated epigenetic changes can alter gene expression and impair cellular functions in immune cells, resulting in autoreactive immune responses. Therefore, elucidating the dysregulated epigenetic mechanisms in the immune system is crucial for understanding the pathogenesis of SLE. In this paper, we review the important roles of epigenetic disorders in the pathogenesis of SLE.

1. Introduction

Systemic lupus erythematosus (SLE) is a chronic prototypic autoimmune disease that results from immune system-mediated inflammation and tissue damage [1]. Aberrant activation of the immune system leads to the production of a broad array of autoantibodies specific for nucleic acids and nucleic acid-binding proteins, including anti-nuclear antibodies (ANAs), anti-double stranded DNA (dsDNA) antibodies, and anti-Smith (Sm) antibodies [2]. The autoreactive immune responses result in several characteristic clinical features, including skin rashes, oral ulcers, inflammatory polyarthritis, serositis, neuropsychiatric disorders, glomerulonephritis, and blood cell abnormalities [3]. SLE is a heterogeneous disease with varying combinations of clinical features and is characterized by a relapsing and remitting clinical course and a highly variable prognosis. SLE primarily affects females of childbearing age, with the highest prevalence in African-American, Asian, and Hispanic populations [4]. Therapy for SLE includes corticosteroids, hydroxychloroquine, immunosuppressants, and biologic agents targeting specific molecular mechanisms such as B cell-activating factor belonging to the tumor necrosis factor family (BAFF, also called BLyS) and type I interferon (IFN) receptor subunit 1 [5].
A line of evidence has demonstrated that a variety of environmental factors trigger autoimmune diseases such as SLE in genetically predisposed individuals [6,7]. SLE exhibits a strong familial accumulation with a much higher frequency among first-degree relatives of patients. SLE develops concordantly in approximately 25–50% of monozygotic twins and 5% of dizygotic twins. In spite of the influence of heredity, most cases appear sporadically. Genetic and environmental factors are involved in the immune system dysregulation that can trigger the development of SLE [8]. Epigenetic mechanisms, including DNA methylation, histone modifications, and microRNA (miRNA) expression, have also been shown to be associated with the pathogenesis of autoimmune diseases [9,10,11,12,13,14,15]. Epigenetic changes affect gene transcription by modulating the chromatin structure without altering the DNA sequence itself [16]. Epigenetic regulation contributes to the maintenance of a normal immune response. Previous reports have demonstrated that histone modifications are associated with the differentiation and function of T cells [17,18,19,20,21]. Revealing the epigenetic dysregulation in immune cells is important for understanding the pathogenesis of SLE and ultimately developing new therapeutic strategies (Figure 1).

2. The Pathogenesis of SLE

A line of evidence has shown that dysregulated adaptive and innate immune responses are closely associated with the pathogenesis of SLE [22]. SLE is an autoimmune disease that is caused by a breakdown in immunological self-tolerance. On the other hand, recent advances have demonstrated that SLE is a type I interferonopathy. To understand the complex pathogenesis of SLE, we review adaptive and innate immune responses in SLE.

2.1. Adaptive Immune Responses in SLE

The adaptive immune system attacks non-self-antigens but not self-antigens, which is referred to as self-tolerance. A breakdown in immunological self-tolerance leads to autoreactive immune responses through the induction of autoreactive lymphocytes, autoantibodies, and the impaired immunosuppressive function of regulatory T cells (Treg) [23,24,25]. The dysregulated adaptive immune responses attack the individual’s own tissues that include self-antigens. Immunological self-tolerance includes central and peripheral tolerance. In primary lymphoid tissues, central tolerance gets rid of autoreactive lymphocytes through apoptosis and receptor editing in B cells and through positive and negative selections in T cells [26,27,28,29]. In secondary lymphoid tissues, peripheral tolerance excludes autoreactive lymphocytes through anergy and follicular exclusion in B cells and through anergy, deletion, and suppression in T cells [30,31,32,33,34].
T follicular helper (Tfh) cells are programmed death receptor-1 (PD-1)+C-X-C motif chemokine receptor 5 (CXCR5)+CD4+ T cells that are involved in B cell differentiation and maturation in germinal centers of secondary lymphoid tissues [35]. Interleukin-12 (IL-12), IL-23, and transforming growth factor-β (TGF-β) induce the expression of B-cell/CLL lymphoma 6 (BCL6) and musculoaponeurotic fibrosarcoma (MAF) for Tfh cell differentiation. Tfh cells produce IL-21 and C-X-C motif chemokine ligand 13 (CXCL13), and play an important role in immunoglobulin class switching and affinity maturation in germinal centers. Tfh cells promote pathogenic B cell responses in SLE [36]. T peripheral helper (Tph) cells are PD-1highCXCR5CD4+ T cells that are associated with B cell differentiation and tissue damage in peripheral inflammatory non-lymphoid tissues [37]. IL-12, TGF-β, IFNα, and IFNλ induce the expression of B lymphocyte-induced maturation protein-1 (BLIMP1) and MAF for Tph cell differentiation. Tph cells express C-C motif chemokine receptor 2 (CCR2), C-X3-C motif chemokine receptor 1 (CX3CR1), and CCR5, and produce IL-21 and CXCL13, similar to Tfh cells. Tph cells accumulate in peripheral inflamed tissues and induce pathogenic B cell responses in SLE [38]. Age-associated B cells (ABCs) are T-box transcription factor 21 (TBX21, also called T-bet)+CD11c+CD11b+CD21 memory B cells that arise with age and are expanded in patients with autoimmune diseases such as SLE [39]. ABCs produce autoantibodies; secrete various cytokines, including IFNγ, tumor necrosis factor α (TNFα), and IL-17; and activate pathogenic T cells as antigen-presenting cells [40,41].

2.2. Innate Immune Responses in SLE

Activation of the innate immune system regulates adaptive immune responses [42]. Innate immune responses have been shown to be closely involved in the pathogenesis of SLE. Both Toll-like receptor (TLR)-dependent and TLR-independent innate immune pathways can induce type I IFN production in SLE. A broad expression of type I IFN-inducible genes, referred to as the IFN signature, has been shown in SLE [43]. In the TLR-dependent pathway, single-stranded RNAs or unmethylated CpG-rich double-stranded DNAs-containing immune complexes access TLR7 or TLR9, respectively, with the help of Fc receptors. Activation of the endosomal TLRs enhances IFNα production through interferon regulatory factor (IRF)5 and IRF7 in plasmacytoid dendritic cells (pDCs) [44]. In the TLR-independent pathways, small RNAs bind to intracytoplasmic RNA sensors, such as retinoic acid inducible gene-I (RIG-I) and melanoma differentiation-associated gene 5 (MDA5), and activate mitochondrial antiviral signaling (MAVS) [45]. Small RNAs also increase the permeability of mitochondria and release oxidized mitochondrial DNA into the cytosol [46]. Cytosolic DNA is associated with the DNA sensor cyclic GMP-AMP synthase (cGAS) and activates the stimulator of interferon genes (STING). These TLR-independent pathways induce IFNβ expression through IRF3 in macrophages.
Neutrophil extracellular traps (NETs) are mesh-like structures that are extruded from activated neutrophils in response to inflammatory stimuli [47]. NETs are composed of decondensed chromatin and intracellular proteins, including high mobility group box 1 (HMGB1), LL37 (a proteolytic fragment of cathelicidin), neutrophil elastase, and myeloperoxidase (MPO), which serve as autoantigens. NETs also include nucleic acids that activate the TLR pathway and the cGAS–STING pathway, resulting in the activation of innate immunity. NET formation, referred to as NETosis, contributes to the development of SLE [48].

3. Epigenetic Regulation of Chromatin Structure and Gene Transcription

Conrad H. Waddington proposed the epigenetic landscape theory that explains a process in which gene regulation modulates development. Epigenetic mechanisms regulate a stably heritable phenotype resulting from changes in a chromosome without alterations in the DNA sequence [49]. Epigenetic changes are conveyed through either mitosis or meiosis and modulate the chromatin structure, resulting in the change to gene transcription [50]. Chromatin is a mixture of DNA and proteins such as histones (H2A, H2B, H3, and H4), and forms chromosomes in the nucleus of eukaryotic cells [16,51]. DNA wraps around the histone proteins and forms the nucleosome that is the fundamental subunit of chromatin. The chromatin structure in regulatory regions of genomic DNA, including promoters and enhancers, alters the accessibility for transcription factors (TFs) [52]. In euchromatin, which is an accessible chromatin state, TFs are associated with genomic DNA and genes are actively transcribed [53]. In heterochromatin, which is a condensed chromatin state, TFs are not associated with genomic DNA and gene transcription is repressed.
DNA methylation means methylation of the fifth position of cytosine (5mC) [54]. DNA is methylated predominantly at the dinucleotide CpG in the promoters of genes [55]. A high degree of DNA methylation suppresses gene transcription by inhibiting the association of DNA and TFs [56]. DNA is methylated by DNA methyltransferases (DNMTs), such as de novo methyltransferases (DNMT3A, DNMT3B) and a maintenance methyltransferase DNMT1 [57,58]. Methyl-CpG-binding proteins (MBPs) that recognize methylated DNA comprise the three structural families [59]. A methyl-CpG-binding domain (MBD) protein family consists of MBD1, MBD2, MBD4, and methyl-CpG-binding protein 2 (MeCP2). DNMT1 maintains DNA methylation through an association with MeCP2 [60]. A SET and RING finger-associated (SRA) domain protein family includes ubiquitin-like with PHD and ring finger domains (UHRF)1 and UHRF2. UHRF1 binds to hemi-methylated DNA and maintains DNA methylation by recruiting DNMT1 [61]. A zinc finger protein family comprises Kaiso and Kaiso-like proteins. DNA demethylation is induced by a decrease in DNMT activity during cell division or by the ten-eleven translocation (TET) family of enzymes (TET1, TET2, and TET3).
Strahl and Allis proposed the histone code hypothesis that multiple histone modifications exhibit specific functions in a combinatorial or sequential fashion [62]. Covalent post-translational modifications in histone N-terminal tails, including acetylation and methylation, function as transcriptionally active or repressive markers [52,63,64]. Active histone markers, such as the acetylation of histone H3 and the methylation of histone H3 at lysine 4 (H3K4), are located on euchromatin and associated with active gene transcription. Repressive histone markers, such as methylation of H3K9 and H3K27, are located on heterochromatin and associated with repressive gene transcription. Histones are acetylated by histone acetyltransferases (HATs) and deacetylated by histone deacetylases (HDACs) [65]. Histones are methylated by histone methyltransferases (HMTs) and demethylated by histone demethylases (HDMs) [66].
miRNAs are a family of approximately 21-nucleotide-long small noncoding RNAs (ncRNAs) that are post-transcriptional regulators [67]. After miRNAs are associated with the 3′-untranslated region of messenger RNAs (mRNAs) of target genes, the perfect complementarity between miRNAs and its targets causes mRNA cleavage and imperfect complementarity induces translational repression [68,69]. Long ncRNAs (lncRNAs) are defined as >200-nucleotide-long ncRNAs and have recently gained attention. lncRNAs govern gene expression and are implicated in the pathogenesis of rheumatic diseases such as SLE [70].

4. Epigenetic Dysregulation in SLE

4.1. Dysregulated DNA Methylation in SLE

The dysregulation of DNA methylation has been demonstrated to relate with aberrant immune systems in SLE (Table 1). CD11a/CD18, which is also called lymphocyte function-associated antigen 1 (LFA-1) or integrin subunit alpha L (ITGAL), is an integrin that regulates leukocyte adhesion and migration in inflamed tissues. CD11a/CD18 overexpression correlates with the development of T cell autoreactivity [71]. The adoptive transfer of CD11a/CD18-overexpressed T cells into syngeneic mice caused a lupus-like disease [72]. DNA hypomethylation in the CD11a/CD18 promoter was identified in T cells from patients with active SLE [73]. CD70 (TNFSF7) is a ligand for CD27 and plays a role in T cell activation [74]. DNA hypomethylation in the CD70 promoter caused CD70 overexpression in SLE CD4+ T cells and induced B cell stimulation in SLE patients [75]. The CD40 ligand (CD40LG) that is expressed on activated CD4+ T cells, such as Tfh, functions as a costimulatory molecule and promotes B cell maturation [76]. The DNA hypomethylation of CD40LG contributes to CD40LG overexpression in CD4+ T cells from women with SLE [77]. The expression and activity of the transcription factor regulatory factor X-box 1 (RFX1) are repressed in SLE CD4+ T cells [78]. As RFX1 recruits DNMT1 and induces DNA methylation, the downregulated expression of RFX1 enhances CD11a/CD18 and CD70 expression in SLE CD4+ T cells. IL-10, which has B cell-promoting effects is elevated in the serum and tissues from SLE patients and induces autoantibodies by B cells [79]. DNA hypomethylation in the IL-10 gene and the recruitment of signal transducer and activator of transcription 3 (STAT3) to the IL-10 promoter and enhancer increase IL-10 expression in SLE T cells. Growth arrest and DNA damage-inducible 45 α (Gadd45α), which is a nuclear protein associated with the maintenance of genomic stability, DNA repair, and suppression of cell growth, plays a role in DNA demethylation [80]. Increased Gadd45α gene expression and global DNA hypomethylation enhanced CD11a/CD18 and CD70 gene expression in SLE CD4+ T cells [81]. Moreover, HMGB1 is associated with Gadd45α in CD4+ T cells during SLE flare [82]. HMGB1 expression is increased in SLE CD4+ T cells and associated with not only CD11a/CD18 and CD70 expression, but also the SLE Disease Activity Index (SLEDAI) score.
Eighty-six differentially methylated CpG sites in 47 genes were demonstrated in naïve CD4+ T cells from SLE patients by a genome-wide DNA methylation study [83]. Significant DNA hypomethylation is observed in type I IFN-regulated genes, such as MX dynamin-like GTPase 1 (MX1), bone marrow stromal cell antigen 2 (BST2), STAT1, tripartite motif containing 22 (TRIM22), IFN-induced proteins with tetratricopeptide repeats 1 (IFIT1), IFIT3, IFN-induced protein 44 like (IFI44L), and ubiquitin specific peptidase 18 (USP18). Another group reported differentially methylated genes, including sphingosine-1-phosphate receptor 3 (S1PR3), CD300 molecule-like family member B (CD300LB), and NACHT, LRR, and PYD domains-containing protein 2 (NLRP2) in SLE CD4+ T cells using a genome-wide DNA methylation experiment [84]. A decrease in signaling through the RAS-mitogen-activated protein kinase (MAPK) pathway contributes to decreased DNMT activity and DNA hypomethylation in T cells from patients with active SLE [85]. Enhanced levels of the catalytic subunit of protein phosphatase 2A (PP2Ac) inhibit the mitogen-activated protein kinase kinase (MEK)/extracellular signal-regulated kinase (ERK) signaling pathway and decreases DNMT1 expression and DNA methylation in SLE T cells [86]. An increased expression of miR-21 and miR-148a decreases the DNMT1 expression and induces DNA hypomethylation, resulting in the overexpression of CD11a/CD18 and CD70 genes in SLE CD4+ T cells [87]. IL-17A induces the production of cytokines and chemokines, such as IL-6 and IL-8, and recruits monocytes and neutrophils. IL-17A is implicated in the development of SLE [88]. Decreased DNMT3A and HDAC1 causes DNA hypomethylation and H3K18 hyperacetylation in the IL-17A gene, respectively, in SLE T cells [89]. The cAMP-responsive element modulator α (CREMα) is highly expressed and associated with the IL-17A promoter, resulting in an increased IL-17A production in SLE T cells. An epigenome-wide study revealed that differential methylated genes that regulate the response to tissue hypoxia and IFN-mediated signaling contributed to lupus nephritis [90]. The downregulation of MBD4 decreased the DNA methylation of the CD70 gene and enhanced CD70 gene expression in SLE CD4+ T cells [91]. Decreased 3-hydroxy butyrate dehydrogenase 2 (BDH2), a modulator of intracellular iron homeostasis, leads to DNA hypomethylation via increasing the amount of intracellular iron in SLE CD4+ T cells [92].
DNA hypomethylation in IFN-associated genes, such as poly (ADP-ribose) polymerase family member 9 (PARP9), IFN-induced transmembrane protein 1 (IFITM1), and IFI44L was demonstrated in CD4+ T cells, B cells, granulocytes, and monocytes from SLE patients [93]. Differentially methylated genes, such as MX1, IFI44L, IFIT1, IFI44, IRF5, IRF7, MHC-class III, PARP9, UHRF1-binding protein 1 (UHRF1BP1), radical S-adenosyl methionine domain containing 2 (RSAD2), phospholipid scramblase 1 (PLSCR1), ubiquitin-conjugating enzyme E2 L3 (UBE2L3), CD45, Ikaros family zinc finger 3 (IKZF3), and histone E3 ubiquitin ligase 3L (DT3XL), were identified in peripheral blood mononuclear cells (PBMCs) from SLE patients [94,95]. An analysis of DNA methylation profiles identified hypomethylated genes, such as IFI44, IFITM1, Y-box binding protein 1 (YBX1), and TATA-box binding protein associated factor 8 (TAF8), and hypermethylated genes, including SRY-box transcription factor 12 (SOX12), ADP-ribosylation factor GTPase-activating protein 3 (ARFGAP3), coiled-coil domain containing 81 (CCDC81), and maternally expressed 3 (MEG3), in SLE B cells [96]. Downregulated UHRF1 enhances the BLC6 expression through an decrease in DNA methylation and trimethylation at H3K27 (H3K27me3) levels in the BCL6 promoter and promotes Tfh cell differentiation in SLE [97].

4.2. Dysregulated Histone Modifications in SLE

In this section, we review the roles of dysregulated histone modifications in aberrant immune responses in SLE (Table 2). In PBMCs from SLE patients, the levels of H3K4me3 are increased in WD repeat-containing protein 5 (WDR5) and solute carrier family 24 member 3 (SLC24A3) genes, and decreased in protein tyrosine phosphatase non-receptor type 22 (PTPN22), methyltransferase 16 (METTL16), LDL receptor-related protein 1B (LRP1B), and cadherin 13 (CDH13) genes [98]. CD70 gene expression is increased in CD4+ T cells from active SLE patients [99]. Acetylation at histone H3 (H3ac) and dimethylation at H3K4 (H3K4me2) levels in the CD70 gene are enhanced in SLE CD4+ T cells. TNFα expressing monocytes were more frequent in SLE patients compared to healthy controls. H3ac levels were not increased but H4ac levels were increased in the TNFα gene in SLE monocytes [100]. The increased expression of PP2Ac contributes to the production of IL-17 by enhancing H3ac through the activation of IRF4 in SLE T cells [101]. A genome-wide analysis revealed that H4ac levels are increased in the genes that are regulated by IRF1 in SLE monocytes [102]. H3K27me3 is increased in the hematopoietic progenitor kinase 1 (HPK1, also called MAP4K1) gene in SLE CD4+ T cells. As a result, downregulating HPK1 induces T cell activation [103]. Enhanced H3K27me3 enrichment in the HPK1 promoter is caused by a decrease in Jumonji domain-containing protein 3 (JMJD3) binding in SLE CD4+ T cells. Global histones H3 and H4 hypoacetylation was observed in CD4+ T cells from active SLE patients [104]. The degree of H3ac was inversely associated with the SLEDAI score. Global H3K9 hypomethylation was demonstrated in CD4+ T cells from both active and inactive SLE patients. However, global levels of H3K4 methylation were similar in CD4+ T cells from SLE patients compared to healthy controls. Sirtuin 1 (SIRT1) mRNA levels were enhanced, while mRNA levels of HDAC2, HDAC7, P300, cyclic AMP response element-binding protein (CBP), enhancer of zeste homolog 2 (EZH2), and suppressor of variegation 3-9 homolog 2 (SUV39H2) were reduced in CD4+ T cells from active SLE patients.
RFX1 decreases the levels of H3ac and increases those of H3K9me3 by recruiting HDAC1 and SUV39H1, respectively [78,105]. Therefore, the downregulated expression of RFX1 enhances CD11a/CD18 and CD70 expression in SLE CD4+ T cells. Overexpressed CREMα suppresses IL-2 expression through HDAC1-mediated H3K18 deacetylation and DNMT3A-mediated DNA hypermethylation in SLE T cells [106]. Reduced IL-2 expression contributes to the decrease in Treg in SLE patients. Trichostatin A (TSA), an inhibitor of HDAC, impairs the increased expression of CD40LG and IL-10 genes, and decreased IFNγ gene expression in SLE CD4+ T cells [107]. TLR2 expression was enhanced in CD4+ T cells, CD8+ T cells, B cells, and monocytes from SLE patients [108]. In SLE CD4+ T cells, TLR2 stimulation increased CD40LG, CD70, IL-6, IL-17A, IL-17F, and TNFα expression and decreased the expression of forkhead box P3 (FOXP3), which is a master regulator of Treg. TLR2 activation enhanced H4ac levels and reduced H3K9me3 levels in the IL-17A and IL-17F genes in SLE CD4+ T cells. TNFα-induced protein 3 (TNFAIP3) expression was downregulated by decreasing the H3K4me3 level in the gene promoter in SLE CD4+ T cells [109]. The reduced expression of TNFAIP3 increased the expression of IFNγ and IL-17. BCL6 was highly expressed and repressed the miR-142-3p/5p expression by increasing H3K27me3 levels and decreasing H3K9/14ac levels in SLE CD4+ T cells [110]. BCL6 recruited EZH2 and HDAC5 to the miR-142-3p/5p promoter and induced the expression of IL-21, inducible T-cell co-stimulator (ICOS), and CD40LG. BCL-6, IL-21, ICOS, and CD40LG play an important role in the development and function of Tfh cells, resulting in CD4+ T cell hyperactivity and autoantibody production in SLE. IL-23 promoted the phosphorylation of STAT3 in T helper 17 (Th17) cells, which are a subset of CD4+ T helper cells defined by the production of IL-17, from SLE patients [111]. IL-23 enhanced the H3K4me3 level and reduced the H3K27me3 level in the retinoic acid receptor-related orphan receptor γt (RORγt) gene, which is a master regulator of Th17 cells. IL-23-induced STAT3 binds to the RORγt gene locus, leading to an increase in RORγt expression.

4.3. Dysregulated miRNA Expression in SLE

Dysregulated miRNA expression contributes to the immunopathogenesis of SLE (Table 3). Estrogen-induced miR-10b-5p is increased in SLE T cells [112]. miR-10b-5p targets serine/arginine-rich splicing factor 1 (SRSF1), which promotes IL-2 production. Therefore, the decrease in SRSF1 impairs Treg differentiation and leads to the persistence of autoreactive T cells in SLE [113]. T cell-restricted Srsf1-deficient mice showed high frequencies of activated T cells producing proinflammatory cytokines and systemic autoimmunity such as lupus-like nephritis [114]. miR-17-5p expression is repressed by E2F transcription factor 2 (E2F2) in SLE B cells [115]. miR-17-5p targets IL-10, which has B cell-promoting effects, resulting in autoantibody production. miR-21 expression is elevated in SLE CD4+ T cells and associated with SLEDAI score [116]. miR-21 targets programmed cell death protein 4 (PDCD4), which suppresses proliferation, IL-10 production, CD40LG expression, and the capacity to drive B cell maturation in SLE CD4+ T cells [117,118,119,120]. miR-21 also targets BDH2, which promotes DNA methylation in SLE CD4+ T cells [92]. IL-6 or TNFα activates NF-kB/p65, which binds to the miR-34a promoter and increases miR-34a expression in the PBMC and CD4+ T cells from SLE patients [121]. miR-34a targets FOXP3, which promotes the development of Treg. miR-98 expression is repressed in SLE CD4+ T cells [122]. miR-98 targets FAS, which promotes the apoptotic signaling pathway. miR-99a-3p expression is downregulated in SLE PBMCs [123]. miR-99a-3p targets eukaryotic translation initiation factor 4E-binding protein 1 (EIF4EBP1), which promotes the autophagy signaling pathway in B cells.
miR-125a expression is downregulated in SLE T cells [124]. miR-125a targets Kruppel-like factor 13 (KLF13), which enhances regulated activation, normal T cell expressed, and secreted (RANTES) expression. miR-142-3p expression is increased in SLE monocyte-derived DCs, which produces C-C motif chemokine ligand 2 (CCL2), CCL5, CXCL8, IL-6, and TNFα [125]. Monocyte-derived DCs attract CD4+ T cells and suppress the production of Treg in SLE. miR-146a expression is downregulated in SLE PBMCs [126,127]. miR-146a is a negative regulator of the type I IFN signaling pathway and is inversely correlated with the SLEDAI score and the IFN score in SLE patients. miR-146a targets IRF5 and STAT1. miR-146a expression is upregulated in SLE Treg [128]. miR-146a targets STAT1, which promotes the Th1 response and is associated with autoimmunity. miR-152-3p expression is increased in SLE B cells [129]. miR-152-3p targets KLF5, which reduces BAFF expression. miR-152-3p expression was elevated in the CD4+ T cells and PBMCs from SLE patients [130]. An increased miR-152-3p expression is correlated with skin rashes, arthritis, anti-dsDNA antibody, and IgG in SLE patients. miR-152-3p induces the autoreactivity of CD4+ T cells and TLR-mediated inflammatory responses by targeting DNMT1, which increases DNA methylation in the myeloid differentiation factor 88 (MyD88) gene. miR-155 expression is repressed in serum, urine, and PBMCs from SLE patients [131,132]. miR-155 targets CAMP response element binding protein (CREB), which promotes PP2A expression. As PP2A inhibits IL-2 production, downregulated miR-155 suppresses IL-2 production in SLE PBMCs. miR-155 expression is negatively correlated with the SLEDAI score and proteinuria, and is positively correlated with white blood cell counts in SLE patients [132].
Estrogen-regulated miR-302d expression was reduced in SLE monocytes [133]. miR-302d targets IRF9, which is involved in the expression of IFN-stimulated genes such as 2′-5′-oligoadenylate synthetase 1 (OAS1) and MX1. miR-302d expression is negatively correlated with IFN score in SLE patients. miR-663 expression is increased in the bone marrow-derived mesenchymal stem cells (BMSCs) from SLE patients [134]. BMSCs inhibit the proliferation and function of immune cells, such as T cells, B cells, natural killer cells, and DCs. miR-663 reduces the proliferation and migration of BMSCs and suppresses the BMSC-mediated decrease in Tfh cells and increase in Treg by targeting TGF-β in SLE patients. miR-663 is associated with the SLEDAI score. miR-4512 expression is decreased in monocytes and macrophages from SLE patients [135]. As miR-4512 targets TLR4, NETosis is induced by the activation of the TLR4 pathway in SLE patients.
lncRNAs are another highly diverse class of ncRNAs that are involved in genomic, transcriptional, and translational regulation of their target genes [136]. A variety of lncRNAs, including growth arrest-specific transcript 5 (GAS5), nuclear paraspeckle assembly transcript 1 (NEAT1), and metastasis-associated lung adenocarcinoma transcript 1 (MALAT1), are implicated in the pathogenesis of SLE [137,138,139].
Table 1. Aberrant DNA methylation in SLE. This table lists DNA methylation states, effects by aberrant DNA methylation, and types of experiments and cells that were examined for DNA methylation evaluation in SLE-associated genes.
Table 1. Aberrant DNA methylation in SLE. This table lists DNA methylation states, effects by aberrant DNA methylation, and types of experiments and cells that were examined for DNA methylation evaluation in SLE-associated genes.
GenesDNA MethylationEffectsTypes of ExperimentsCellsRefs.
CD11a/CD18hypomethylationleukocyte adhesion and migration in inflamed tissuesin vitroT cells[73]
CD11a/CD18hypomethylationleukocyte adhesion and migration in inflamed tissuesin vitroCD4+ T cells[78,81,87]
CD70hypomethylationB cell activationin vitroCD4+ T cells[75,78,81,87,91]
CD40LGhypomethylationB cell maturationin vitroCD4+ T cells[77]
IL-10hypomethylationB cell activationin vitroT cells[79]
MX1, BST2, STAT1, TRIM22, IFIT1, IFIT3, IFI44L, USP18hypomethylationtype I IFN-mediated responsesin vitronaïve CD4+ T cells[83]
S1PR3, CD300LB, NLRP2hypomethylation in vitroCD4+ T cells[84]
IL-17Ahypomethylationrecruitment of monocytes and neutrophilsin vitroT cells[89]
PARP9, IFITM1, IFI44Lhypomethylationtype I IFN-mediated responsesin vitroCD4+ T cells, B cells, granulocytes, monocytes[93]
MX1, IFI44L, PARP9, DT3XL, IFIT1, IFI44, RSAD2, PLSCR1, IRF7hypomethylationtype I IFN-mediated responsesin vitroPBMCs[95]
IFI44, IFITM1, YBX1, TAF8hypomethylation in vitroB cells[96]
SOX12, ARFGAP3, CCDC81, MEG3hypermethylation in vitroB cells[96]
BCL6hypomethylationTfh cell differentiationin vitronaïve CD4+ T cells[97]
IL-2hypermethylationTreg suppressionin vitroT cells[106]
Table 2. Aberrant histone modifications in SLE. This table lists histone modification states, effects by aberrant histone modifications, and types of experiments and cells that were examined for histone modification evaluation in SLE-associated genes.
Table 2. Aberrant histone modifications in SLE. This table lists histone modification states, effects by aberrant histone modifications, and types of experiments and cells that were examined for histone modification evaluation in SLE-associated genes.
GenesHistone ModificationsEffectsTypes of ExperimentsCellsRefs.
WDR5, SLC24A3high H3K4me3 in vitroPBMCs[98]
PTPN22, METTL16, LRP1B, CDH13low H3K4me3 in vitroPBMCs[98]
CD70high H3K4me2, high H3acB cell activationin vitroCD4+ T cells[99]
TNFαhigh H4acinflammatory responsesin vitromonocytes[100]
IL-17high H3acrecruitment of monocytes and neutrophilsin vitroT cells[101]
IL-17A, IL-17Fhigh H4ac, low H3K9me3recruitment of monocytes and neutrophilsin vitroCD4+ T cells[108]
HPK1high H3K27me3T cell activationin vitroCD4+ T cells[103]
CD11a/CD18low H3K9me3, high H3acleukocyte adhesion and migration in inflamed tissuesin vitroCD4+ T cells[78,105]
CD70low H3K9me3, high H3acT cell activationin vitroCD4+ T cells[78,105]
IL-2low H3K18acTreg suppressionin vitroT cells[106]
TNFAIP3low H3K4me3production of IFNγ and IL-17in vitroCD4+ T cells[109]
miR-142-3p/5phigh H3K27me3, low H3K9/14acproduction of IL-21, ICOS, and CD40LG, and Tfh cell differentiationin vitroCD4+ T cells[110]
RORγthigh H3K4me3, low H3K27me3Th17 differentiationin vitroCD4+ T cells[111]
Table 3. Aberrant miRNA expression in SLE. This table lists miRNA expression, effects by aberrant miRNA expression, and types of experiments and cells that were examined for miRNA expression in SLE-associated genes.
Table 3. Aberrant miRNA expression in SLE. This table lists miRNA expression, effects by aberrant miRNA expression, and types of experiments and cells that were examined for miRNA expression in SLE-associated genes.
miRNA ExpressionTarget GenesEffectsTypes of ExperimentsCellsRefs.
miR-10b-5p upregulationSRSF1Treg suppressionin vitroT cells[112]
miR-17-5p downregulationIL-10autoantibody productionin vitroB cells[115]
miR-21 upregulationPDCD4cell proliferation and B cell maturationin vitroCD4+ T cells[116]
miR-21 upregulationBDH2suppression of DNA methylationin vitroCD4+ T cells[92]
miR-34a upregulationFOXP3Treg suppressionin vitroPBMCs, CD4+ T cells[121]
miR-98 downregulationFASapoptosisin vitroCD4+ T cells[122]
miR-99a-3p downregulationEIF4EBP1autophagyin vitroPBMCs[123]
miR-125a downregulationKLF13increase in RANTES expressionin vitroT cells[124]
miR-146a downregulationSTAT1Th1 responsesin vitroPBMCs[126,127]
miR-152-3p upregulationKLF5increase in BAFF expressionin vitroB cells[129]
miR-152-3p upregulationDNMT1autoreactive CD4+ T cell responses and TLR-mediated inflammatory responsesin vitroPBMCs, CD4+ T cells[130]
miR-155 downregulationCREBreduced IL-2 productionin vitroPBMCs[131,132]
miR-302d downregulationIRF9type I IFN-mediated responsesin vitromonocytes[133]
miR-663 upregulationTGF-β1Tfh cell activation and Treg suppressionin vitroBMSCs[134]
miR4512 downregulationTLRNETosisin vitromonocytes, macrophages[135]

5. Conclusions

SLE is a systemic autoimmune disease characterized by autoreactive immune responses and a type I IFN signature. Epigenetic mechanisms regulate gene transcription by modulating the chromatin structure. Although genetic and environmental factors have been shown to be involved in the pathogenesis of SLE, increasing evidence has demonstrated that dysregulated epigenetic changes contribute to aberrant immune responses, resulting in the progression of SLE. From the perspective of adaptive immunity, dysregulated epigenetic mechanisms play a critical role in the activation of T cells in SLE. Activated Tfh cells promote autoantibody production. Epigenetic dysregulation also suppresses Treg differentiation and increases the number of autoreactive lymphocytes. Regarding innate immunity, dysregulated epigenetic changes promote type I IFN production that activates type I IFN-regulated genes in SLE. Thus, the complex pathogenesis of SLE has been unraveled. Recently, the development of genome-wide analyses using next-generation sequencing has minutely elucidated the roles of epigenetic mechanisms as well as the molecules that influence epigenetic changes in SLE. These analyses will facilitate the development of novel drugs targeting the dysregulated epigenetic changes. Advances in our understanding of the roles of epigenetic dysregulation in SLE will shed further light on the pathogenesis of SLE and pave the way for discovering new therapeutic strategies and biomarkers for SLE.

Funding

This work was supported by Japan Society for the Promotion of Science KAKENHI Grant Number 21K07326 (T.M.).

Institutional Review Board Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

Not applicable.

Conflicts of Interest

The authors declare no conflicts of interest.

References

  1. Tsokos, G.C. Systemic lupus erythematosus. N. Engl. J. Med. 2011, 365, 2110–2121. [Google Scholar] [CrossRef] [PubMed]
  2. Olsen, N.J.; Karp, D.R. Autoantibodies and SLE: The threshold for disease. Nat. Rev. Rheumatol. 2014, 10, 181–186. [Google Scholar] [CrossRef]
  3. Rahman, A.; Isenberg, D.A. Systemic lupus erythematosus. N. Engl. J. Med. 2008, 358, 929–939. [Google Scholar] [CrossRef] [PubMed]
  4. Barber, M.R.W.; Drenkard, C.; Falasinnu, T.; Hoi, A.; Mak, A.; Kow, N.Y.; Svenungsson, E.; Peterson, J.; Clarke, A.E.; Ramsey-Goldman, R. Global epidemiology of systemic lupus erythematosus. Nat. Rev. Rheumatol. 2021, 17, 515–532. [Google Scholar] [CrossRef]
  5. Fanouriakis, A.; Kostopoulou, M.; Andersen, J.; Aringer, M.; Arnaud, L.; Bae, S.C.; Boletis, J.; Bruce, I.N.; Cervera, R.; Doria, A.; et al. EULAR recommendations for the management of systemic lupus erythematosus: 2023 update. Ann. Rheum. Dis. 2024, 83, 15–29. [Google Scholar] [CrossRef]
  6. Wahren-Herlenius, M.; Dorner, T. Immunopathogenic mechanisms of systemic autoimmune disease. Lancet 2013, 382, 819–831. [Google Scholar] [CrossRef]
  7. Ellis, J.A.; Kemp, A.S.; Ponsonby, A.L. Gene-environment interaction in autoimmune disease. Expert. Rev. Mol. Med. 2014, 16, e4. [Google Scholar] [CrossRef] [PubMed]
  8. Sutanto, H.; Yuliasih, Y. Disentangling the Pathogenesis of Systemic Lupus Erythematosus: Close Ties between Immunological, Genetic and Environmental Factors. Medicina 2023, 59, 1033. [Google Scholar] [CrossRef]
  9. Costenbader, K.H.; Gay, S.; Alarcon-Riquelme, M.E.; Iaccarino, L.; Doria, A. Genes, epigenetic regulation and environmental factors: Which is the most relevant in developing autoimmune diseases? Autoimmun. Rev. 2012, 11, 604–609. [Google Scholar] [CrossRef]
  10. Wada, T.T.; Araki, Y.; Sato, K.; Aizaki, Y.; Yokota, K.; Kim, Y.T.; Oda, H.; Kurokawa, R.; Mimura, T. Aberrant histone acetylation contributes to elevated interleukin-6 production in rheumatoid arthritis synovial fibroblasts. Biochem. Biophys. Res. Commun. 2014, 444, 682–686. [Google Scholar] [CrossRef]
  11. Araki, Y.; Tsuzuki Wada, T.; Aizaki, Y.; Sato, K.; Yokota, K.; Fujimoto, K.; Kim, Y.T.; Oda, H.; Kurokawa, R.; Mimura, T. Histone Methylation and STAT-3 Differentially Regulate Interleukin-6-Induced Matrix Metalloproteinase Gene Activation in Rheumatoid Arthritis Synovial Fibroblasts. Arthritis Rheumatol. 2016, 68, 1111–1123. [Google Scholar] [CrossRef] [PubMed]
  12. Araki, Y.; Mimura, T. The Mechanisms Underlying Chronic Inflammation in Rheumatoid Arthritis from the Perspective of the Epigenetic Landscape. J. Immunol. Res. 2016, 2016, 6290682. [Google Scholar] [CrossRef] [PubMed]
  13. Araki, Y.; Mimura, T. The Histone Modification Code in the Pathogenesis of Autoimmune Diseases. Mediators Inflamm. 2017, 2017, 2608605. [Google Scholar] [CrossRef]
  14. Araki, Y.; Mimura, T. Matrix Metalloproteinase Gene Activation Resulting from Disordred Epigenetic Mechanisms in Rheumatoid Arthritis. Int. J. Mol. Sci. 2017, 18, 905. [Google Scholar] [CrossRef] [PubMed]
  15. Araki, Y.; Aizaki, Y.; Sato, K.; Oda, H.; Kurokawa, R.; Mimura, T. Altered gene expression profiles of histone lysine methyltransferases and demethylases in rheumatoid arthritis synovial fibroblasts. Clin. Exp. Rheumatol. 2018, 36, 314–316. [Google Scholar] [PubMed]
  16. Bernstein, B.E.; Meissner, A.; Lander, E.S. The mammalian epigenome. Cell 2007, 128, 669–681. [Google Scholar] [CrossRef] [PubMed]
  17. Wei, G.; Wei, L.; Zhu, J.; Zang, C.; Hu-Li, J.; Yao, Z.; Cui, K.; Kanno, Y.; Roh, T.Y.; Watford, W.T.; et al. Global mapping of H3K4me3 and H3K27me3 reveals specificity and plasticity in lineage fate determination of differentiating CD4+ T cells. Immunity 2009, 30, 155–167. [Google Scholar] [CrossRef]
  18. Araki, Y.; Fann, M.; Wersto, R.; Weng, N.P. Histone acetylation facilitates rapid and robust memory CD8 T cell response through differential expression of effector molecules (eomesodermin and its targets: Perforin and granzyme B). J. Immunol. 2008, 180, 8102–8108. [Google Scholar] [CrossRef]
  19. Araki, Y.; Wang, Z.; Zang, C.; Wood, W.H., 3rd; Schones, D.; Cui, K.; Roh, T.Y.; Lhotsky, B.; Wersto, R.P.; Peng, W.; et al. Genome-wide analysis of histone methylation reveals chromatin state-based regulation of gene transcription and function of memory CD8+ T cells. Immunity 2009, 30, 912–925. [Google Scholar] [CrossRef]
  20. Araki Y: Role of histone modifications in differentiation and effector function of CD8 T cells: Update review including genome-wide analysis. Jpn. J. Clin. Immunol. 2011, 34, 131–137. [CrossRef]
  21. Weng, N.P.; Araki, Y.; Subedi, K. The molecular basis of the memory T cell response: Differential gene expression and its epigenetic regulation. Nat. Rev. Immunol. 2012, 12, 306–315. [Google Scholar] [CrossRef]
  22. Pan, L.; Lu, M.P.; Wang, J.H.; Xu, M.; Yang, S.R. Immunological pathogenesis and treatment of systemic lupus erythematosus. World J. Pediatr. 2020, 16, 19–30. [Google Scholar] [CrossRef] [PubMed]
  23. Li, H.; Boulougoura, A.; Endo, Y.; Tsokos, G.C. Abnormalities of T cells in systemic lupus erythematosus: New insights in pathogenesis and therapeutic strategies. J. Autoimmun. 2022, 132, 102870. [Google Scholar] [CrossRef] [PubMed]
  24. Hamilton, J.A.; Hsu, H.C.; Mountz, J.D. Autoreactive B cells in SLE, villains or innocent bystanders? Immunol. Rev. 2019, 292, 120–138. [Google Scholar] [CrossRef]
  25. Valencia, X.; Yarboro, C.; Illei, G.; Lipsky, P.E. Deficient CD4+CD25high T regulatory cell function in patients with active systemic lupus erythematosus. J. Immunol. 2007, 178, 2579–2588. [Google Scholar] [CrossRef]
  26. Enders, A.; Bouillet, P.; Puthalakath, H.; Xu, Y.; Tarlinton, D.M.; Strasser, A. Loss of the pro-apoptotic BH3-only Bcl-2 family member Bim inhibits BCR stimulation-induced apoptosis and deletion of autoreactive B cells. J. Exp. Med. 2003, 198, 1119–1126. [Google Scholar] [CrossRef] [PubMed]
  27. Pelanda, R.; Torres, R.M. Receptor editing for better or for worse. Curr. Opin. Immunol. 2006, 18, 184–190. [Google Scholar] [CrossRef]
  28. von Boehmer, H. Positive selection of lymphocytes. Cell 1994, 76, 219–228. [Google Scholar] [CrossRef]
  29. Starr, T.K.; Jameson, S.C.; Hogquist, K.A. Positive and negative selection of T cells. Annu. Rev. Immunol. 2003, 21, 139–176. [Google Scholar] [CrossRef]
  30. Cambier, J.C.; Gauld, S.B.; Merrell, K.T.; Vilen, B.J. B-cell anergy: From transgenic models to naturally occurring anergic B cells? Nat. Rev. Immunol. 2007, 7, 633–643. [Google Scholar] [CrossRef]
  31. Cyster, J.G.; Hartley, S.B.; Goodnow, C.C. Competition for follicular niches excludes self-reactive cells from the recirculating B-cell repertoire. Nature 1994, 371, 389–395. [Google Scholar] [CrossRef] [PubMed]
  32. Powell, J.D. The induction and maintenance of T cell anergy. Clin. Immunol. 2006, 120, 239–246. [Google Scholar] [CrossRef] [PubMed]
  33. Van Parijs, L.; Abbas, A.K. Homeostasis and self-tolerance in the immune system: Turning lymphocytes off. Science 1998, 280, 243–248. [Google Scholar] [CrossRef]
  34. Sakaguchi, S.; Sakaguchi, N.; Asano, M.; Itoh, M.; Toda, M. Immunologic self-tolerance maintained by activated T cells expressing IL-2 receptor alpha-chains (CD25). Breakdown of a single mechanism of self-tolerance causes various autoimmune diseases. J. Immunol. 1995, 155, 1151–1164. [Google Scholar] [CrossRef]
  35. Ueno H: T follicular helper cells in human autoimmunity. Curr. Opin. Immunol. 2016, 43, 24–31. [CrossRef]
  36. Blanco P, Ueno H, Schmitt N: T follicular helper (Tfh) cells in lupus: Activation and involvement in SLE pathogenesis. Eur. J. Immunol. 2016, 46, 281–290. [CrossRef]
  37. Marks, K.E.; Rao, D.A. T peripheral helper cells in autoimmune diseases. Immunol. Rev. 2022, 307, 191–202. [Google Scholar] [CrossRef]
  38. Bocharnikov, A.V.; Keegan, J.; Wacleche, V.S.; Cao, Y.; Fonseka, C.Y.; Wang, G.; Muise, E.S.; Zhang, K.X.; Arazi, A.; Keras, G.; et al. PD-1hiCXCR5- T peripheral helper cells promote B cell responses in lupus via MAF and IL-21. JCI Insight 2019, 4, e130062. [Google Scholar] [CrossRef] [PubMed]
  39. Wehr, C.; Eibel, H.; Masilamani, M.; Illges, H.; Schlesier, M.; Peter, H.H.; Warnatz, K. A new CD21low B cell population in the peripheral blood of patients with SLE. Clin. Immunol. 2004, 113, 161–171. [Google Scholar] [CrossRef]
  40. Liu, Y.; Zhou, S.; Qian, J.; Wang, Y.; Yu, X.; Dai, D.; Dai, M.; Wu, L.; Liao, Z.; Xue, Z.; et al. T-bet+CD11c+ B cells are critical for antichromatin immunoglobulin G production in the development of lupus. Arthritis Res. Ther. 2017, 19, 225. [Google Scholar] [CrossRef]
  41. Mouat, I.C.; Goldberg, E.; Horwitz, M.S. Age-associated B cells in autoimmune diseases. Cell. Mol. Life Sci. 2022, 79, 402. [Google Scholar] [CrossRef]
  42. Bolouri, N.; Akhtari, M.; Farhadi, E.; Mansouri, R.; Faezi, S.T.; Jamshidi, A.; Mahmoudi, M. Role of the innate and adaptive immune responses in the pathogenesis of systemic lupus erythematosus. Inflamm. Res Off. J. Eur. Histamine Res. Soc. 2022, 71, 537–554. [Google Scholar] [CrossRef] [PubMed]
  43. Psarras, A.; Wittmann, M.; Vital, E.M. Emerging concepts of type I interferons in SLE pathogenesis and therapy. Nat. Rev. Rheumatol. 2022, 18, 575–590. [Google Scholar] [CrossRef] [PubMed]
  44. Barrat, F.J.; Meeker, T.; Gregorio, J.; Chan, J.H.; Uematsu, S.; Akira, S.; Chang, B.; Duramad, O.; Coffman, R.L. Nucleic acids of mammalian origin can act as endogenous ligands for Toll-like receptors and may promote systemic lupus erythematosus. J. Exp. Med. 2005, 202, 1131–1139. [Google Scholar] [CrossRef] [PubMed]
  45. Kato, H.; Takeuchi, O.; Mikamo-Satoh, E.; Hirai, R.; Kawai, T.; Matsushita, K.; Hiiragi, A.; Dermody, T.S.; Fujita, T.; Akira, S. Length-dependent recognition of double-stranded ribonucleic acids by retinoic acid-inducible gene-I and melanoma differentiation-associated gene 5. J. Exp. Med. 2008, 205, 1601–1610. [Google Scholar] [CrossRef]
  46. Ablasser, A.; Goldeck, M.; Cavlar, T.; Deimling, T.; Witte, G.; Röhl, I.; Hopfner, K.P.; Ludwig, J.; Hornung, V. cGAS produces a 2′-5′-linked cyclic dinucleotide second messenger that activates STING. Nature 2013, 498, 380–384. [Google Scholar] [CrossRef] [PubMed]
  47. Branzk, N.; Lubojemska, A.; Hardison, S.E.; Wang, Q.; Gutierrez, M.G.; Brown, G.D.; Papayannopoulos, V. Neutrophils sense microbe size and selectively release neutrophil extracellular traps in response to large pathogens. Nat. Immunol. 2014, 15, 1017–1025. [Google Scholar] [CrossRef]
  48. Villanueva, E.; Yalavarthi, S.; Berthier, C.C.; Hodgin, J.B.; Khandpur, R.; Lin, A.M.; Rubin, C.J.; Zhao, W.; Olsen, S.H.; Klinker, M.; et al. Netting neutrophils induce endothelial damage, infiltrate tissues, and expose immunostimulatory molecules in systemic lupus erythematosus. J. Immunol. 2011, 187, 538–552. [Google Scholar] [CrossRef]
  49. Berger SL, Kouzarides T, Shiekhattar R, Shilatifard A: An operational definition of epigenetics. Genes Dev. 2009, 23, 781–783.
  50. Golbabapour, S.; Abdulla, M.A.; Hajrezaei, M. A concise review on epigenetic regulation: Insight into molecular mechanisms. Int. J. Mol. Sci. 2011, 12, 8661–8694. [Google Scholar] [CrossRef]
  51. Bassett, A.; Cooper, S.; Wu, C.; Travers, A. The folding and unfolding of eukaryotic chromatin. Curr. Opin. Genet. Dev. 2009, 19, 159–165. [Google Scholar] [CrossRef] [PubMed]
  52. Li, B.; Carey, M.; Workman, J.L. The role of chromatin during transcription. Cell 2007, 128, 707–719. [Google Scholar] [CrossRef]
  53. Mendenhall, E.M.; Bernstein, B.E. Chromatin state maps: New technologies, new insights. Curr. Opin. Genet. Dev. 2008, 18, 109–115. [Google Scholar] [CrossRef]
  54. Smith, Z.D.; Meissner, A. DNA methylation: Roles in mammalian development. Nat. Rev. Genet. 2013, 14, 204–220. [Google Scholar] [CrossRef] [PubMed]
  55. Deaton, A.M.; Bird, A. CpG islands and the regulation of transcription. Genes Dev. 2011, 25, 1010–1022. [Google Scholar] [CrossRef]
  56. Eden, S.; Cedar, H. Role of DNA methylation in the regulation of transcription. Curr. Opin. Genet. Dev. 1994, 4, 255–259. [Google Scholar] [CrossRef]
  57. Okano, M.; Bell, D.W.; Haber, D.A.; Li, E. DNA methyltransferases Dnmt3a and Dnmt3b are essential for de novo methylation and mammalian development. Cell 1999, 99, 247–257. [Google Scholar] [CrossRef] [PubMed]
  58. Pradhan, S.; Esteve, P.O. Mammalian DNA (cytosine-5) methyltransferases and their expression. Clin. Immunol. 2003, 109, 6–16. [Google Scholar] [CrossRef]
  59. Buck-Koehntop, B.A.; Defossez, P.A. On how mammalian transcription factors recognize methylated DNA. Epigenetics 2013, 8, 131–137. [Google Scholar] [CrossRef]
  60. Kimura, H.; Shiota, K. Methyl-CpG-binding protein, MeCP2, is a target molecule for maintenance DNA methyltransferase, Dnmt1. J. Biol. Chem. 2003, 278, 4806–4812. [Google Scholar] [CrossRef]
  61. Nishiyama, A.; Yamaguchi, L.; Sharif, J.; Johmura, Y.; Kawamura, T.; Nakanishi, K.; Shimamura, S.; Arita, K.; Kodama, T.; Ishikawa, F.; et al. Uhrf1-dependent H3K23 ubiquitylation couples maintenance DNA methylation and replication. Nature 2013, 502, 249–253. [Google Scholar] [CrossRef] [PubMed]
  62. Strahl, B.D.; Allis, C.D. The language of covalent histone modifications. Nature 2000, 403, 41–45. [Google Scholar] [CrossRef]
  63. Berger, S.L. The complex language of chromatin regulation during transcription. Nature 2007, 447, 407–412. [Google Scholar] [CrossRef]
  64. Kouzarides, T. Chromatin modifications and their function. Cell 2007, 128, 693–705. [Google Scholar] [CrossRef]
  65. Kuo, M.H.; Allis, C.D. Roles of histone acetyltransferases and deacetylases in gene regulation. Bioessays 1998, 20, 615–626. [Google Scholar] [CrossRef]
  66. Greer, E.L.; Shi, Y. Histone methylation: A dynamic mark in health, disease and inheritance. Nat. Rev. Genet. 2012, 13, 343–357. [Google Scholar] [CrossRef]
  67. Fabian, M.R.; Sonenberg, N.; Filipowicz, W. Regulation of mRNA translation and stability by microRNAs. Annu. Rev. Biochem. 2010, 79, 351–379. [Google Scholar] [CrossRef]
  68. He, L.; Hannon, G.J. MicroRNAs: Small RNAs with a big role in gene regulation. Nat. Rev. Genet. 2004, 5, 522–531. [Google Scholar] [CrossRef] [PubMed]
  69. Bartel, D.P. MicroRNAs: Target recognition and regulatory functions. Cell 2009, 136, 215–233. [Google Scholar] [CrossRef]
  70. Tang, Y.; Zhou, T.; Yu, X.; Xue, Z.; Shen, N. The role of long non-coding RNAs in rheumatic diseases. Nat. Rev. Rheumatol. 2017, 13, 657–669. [Google Scholar] [CrossRef]
  71. Richardson, B.; Powers, D.; Hooper, F.; Yung, R.L.; O’Rourke, K. Lymphocyte function-associated antigen 1 overexpression and T cell autoreactivity. Arthritis Rheum. 1994, 37, 1363–1372. [Google Scholar] [CrossRef]
  72. Yung, R.; Powers, D.; Johnson, K.; Amento, E.; Carr, D.; Laing, T.; Yang, J.; Chang, S.; Hemati, N.; Richardson, B. Mechanisms of drug-induced lupus, I.I. T cells overexpressing lymphocyte function-associated antigen 1 become autoreactive and cause a lupuslike disease in syngeneic mice. J. Clin. Investig. 1996, 97, 2866–2871. [Google Scholar] [CrossRef] [PubMed]
  73. Lu, Q.; Kaplan, M.; Ray, D.; Zacharek, S.; Gutsch, D.; Richardson, B. Demethylation of ITGAL (CD11a) regulatory sequences in systemic lupus erythematosus. Arthritis Rheum. 2002, 46, 1282–1291. [Google Scholar] [CrossRef] [PubMed]
  74. Lens, S.M.; Tesselaar, K.; van Oers, M.H.; van Lier, R.A. Control of lymphocyte function through CD27-CD70 interactions. Semin. Immunol. 1998, 10, 491–499. [Google Scholar] [CrossRef]
  75. Lu, Q.; Wu, A.; Richardson, B.C. Demethylation of the same promoter sequence increases CD70 expression in lupus T cells and T cells treated with lupus-inducing drugs. J. Immunol. 2005, 174, 6212–6219. [Google Scholar] [CrossRef] [PubMed]
  76. Van Kooten, C.; Banchereau, J. CD40-CD40 ligand: A multifunctional receptor-ligand pair. Adv. Immunol. 1996, 61, 1–77. [Google Scholar]
  77. Lu, Q.; Wu, A.; Tesmer, L.; Ray, D.; Yousif, N.; Richardson, B. Demethylation of CD40LG on the inactive X in T cells from women with lupus. J. Immunol. 2007, 179, 6352–6358. [Google Scholar] [CrossRef]
  78. Zhao, M.; Sun, Y.; Gao, F.; Wu, X.; Tang, J.; Yin, H.; Luo, Y.; Richardson, B.; Lu, Q. Epigenetics and SLE: RFX1 downregulation causes CD11a and CD70 overexpression by altering epigenetic modifications in lupus CD4+ T cells. J. Autoimmun. 2010, 35, 58–69. [Google Scholar] [CrossRef]
  79. Hedrich, C.M.; Rauen, T.; Apostolidis, S.A.; Grammatikos, A.P.; Rodriguez Rodriguez, N.; Ioannidis, C.; Kyttaris, V.C.; Crispin, J.C.; Tsokos, G.C. Stat3 promotes IL-10 expression in lupus T cells through trans-activation and chromatin remodeling. Proc. Natl. Acad. Sci. USA 2014, 111, 13457–13462. [Google Scholar] [CrossRef]
  80. Barreto, G.; Schafer, A.; Marhold, J.; Stach, D.; Swaminathan, S.K.; Handa, V.; Doderlein, G.; Maltry, N.; Wu, W.; Lyko, F.; et al. Gadd45a promotes epigenetic gene activation by repair-mediated DNA demethylation. Nature 2007, 445, 671–675. [Google Scholar] [CrossRef]
  81. Li, Y.; Zhao, M.; Yin, H.; Gao, F.; Wu, X.; Luo, Y.; Zhao, S.; Zhang, X.; Su, Y.; Hu, N.; et al. Overexpression of the growth arrest and DNA damage-induced 45alpha gene contributes to autoimmunity by promoting DNA demethylation in lupus T cells. Arthritis Rheum. 2010, 62, 1438–1447. [Google Scholar] [CrossRef]
  82. Li, Y.; Huang, C.; Zhao, M.; Liang, G.; Xiao, R.; Yung, S.; Chan, T.M.; Lu, Q. A possible role of HMGB1 in DNA demethylation in CD4+ T cells from patients with systemic lupus erythematosus. Clin. Dev. Immunol. 2013, 2013, 206298. [Google Scholar] [CrossRef] [PubMed]
  83. Coit, P.; Jeffries, M.; Altorok, N.; Dozmorov, M.G.; Koelsch, K.A.; Wren, J.D.; Merrill, J.T.; McCune, W.J.; Sawalha, A.H. Genome-wide DNA methylation study suggests epigenetic accessibility and transcriptional poising of interferon-regulated genes in naive CD4+ T cells from lupus patients. J. Autoimmun. 2013, 43, 78–84. [Google Scholar] [CrossRef] [PubMed]
  84. Zhao, M.; Liu, S.; Luo, S.; Wu, H.; Tang, M.; Cheng, W.; Zhang, Q.; Zhang, P.; Yu, X.; Xia, Y.; et al. DNA methylation and mRNA and microRNA expression of SLE CD4+ T cells correlate with disease phenotype. J. Autoimmun. 2014, 54, 127–136. [Google Scholar] [CrossRef]
  85. Deng, C.; Kaplan, M.J.; Yang, J.; Ray, D.; Zhang, Z.; McCune, W.J.; Hanash, S.M.; Richardson, B.C. Decreased Ras-mitogen-activated protein kinase signaling may cause DNA hypomethylation in T lymphocytes from lupus patients. Arthritis Rheum. 2001, 44, 397–407. [Google Scholar] [CrossRef] [PubMed]
  86. Sunahori, K.; Nagpal, K.; Hedrich, C.M.; Mizui, M.; Fitzgerald, L.M.; Tsokos, G.C. The catalytic subunit of protein phosphatase 2A (PP2Ac) promotes DNA hypomethylation by suppressing the phosphorylated mitogen-activated protein kinase/extracellular signal-regulated kinase (ERK) kinase (MEK)/phosphorylated ERK/DNMT1 protein pathway in T-cells from controls and systemic lupus erythematosus patients. J. Biol. Chem. 2013, 288, 21936–21944. [Google Scholar] [PubMed]
  87. Pan, W.; Zhu, S.; Yuan, M.; Cui, H.; Wang, L.; Luo, X.; Li, J.; Zhou, H.; Tang, Y.; Shen, N. MicroRNA-21 and microRNA-148a contribute to DNA hypomethylation in lupus CD4+ T cells by directly and indirectly targeting DNA methyltransferase 1. J. Immunol. 2010, 184, 6773–6781. [Google Scholar] [CrossRef]
  88. Crispin, J.C.; Oukka, M.; Bayliss, G.; Cohen, R.A.; Van Beek, C.A.; Stillman, I.E.; Kyttaris, V.C.; Juang, Y.T.; Tsokos, G.C. Expanded double negative T cells in patients with systemic lupus erythematosus produce IL-17 and infiltrate the kidneys. J. Immunol. 2008, 181, 8761–8766. [Google Scholar] [CrossRef]
  89. Rauen, T.; Hedrich, C.M.; Juang, Y.T.; Tenbrock, K.; Tsokos, G.C. cAMP-responsive element modulator (CREM)alpha protein induces interleukin 17A expression and mediates epigenetic alterations at the interleukin-17A gene locus in patients with systemic lupus erythematosus. J. Biol. Chem. 2011, 286, 43437–43446. [Google Scholar] [CrossRef]
  90. Mok, A.; Solomon, O.; Nayak, R.R.; Coit, P.; Quach, H.L.; Nititham, J.; Sawalha, A.H.; Barcellos, L.F.; Criswell, L.A.; Chung, S.A. Genome-wide profiling identifies associations between lupus nephritis and differential methylation of genes regulating tissue hypoxia and type 1 interferon responses. Lupus. Sci. Med. 2016, 3, e000183. [Google Scholar] [CrossRef]
  91. Liao, W.; Li, M.; Wu, H.; Jia, S.; Zhang, N.; Dai, Y.; Zhao, M.; Lu, Q. Down-regulation of MBD4 contributes to hypomethylation and overexpression of CD70 in CD4+ T cells in systemic lupus erythematosus. Clin. Epigenetics 2017, 9, 104. [Google Scholar] [CrossRef] [PubMed]
  92. Zhao, M.; Li, M.Y.; Gao, X.F.; Jia, S.J.; Gao, K.Q.; Zhou, Y.; Zhang, H.H.; Huang, Y.; Wang, J.; Wu, H.J.; et al. Downregulation of BDH2 modulates iron homeostasis and promotes DNA demethylation in CD4+ T cells of systemic lupus erythematosus. Clin. Immunol. 2018, 187, 113–121. [Google Scholar] [CrossRef]
  93. Ulff-Møller, C.J.; Asmar, F.; Liu, Y.; Svendsen, A.J.; Busato, F.; Grønbaek, K.; Tost, J.; Jacobsen, S. Twin DNA Methylation Profiling Reveals Flare-Dependent Interferon Signature and B Cell Promoter Hypermethylation in Systemic Lupus Erythematosus. Arthritis Rheumatol. 2018, 70, 878–890. [Google Scholar] [CrossRef]
  94. Imgenberg-Kreuz, J.; Carlsson Almlöf, J.; Leonard, D.; Alexsson, A.; Nordmark, G.; Eloranta, M.L.; Rantapää-Dahlqvist, S.; Bengtsson, A.A.; Jönsen, A.; Padyukov, L.; et al. DNA methylation mapping identifies gene regulatory effects in patients with systemic lupus erythematosus. Ann. Rheum. Dis. 2018, 77, 736–743. [Google Scholar] [CrossRef]
  95. Joseph, S.; George, N.I.; Green-Knox, B.; Treadwell, E.L.; Word, B.; Yim, S.; Lyn-Cook, B. Epigenome-wide association study of peripheral blood mononuclear cells in systemic lupus erythematosus: Identifying DNA methylation signatures associated with interferon-related genes based on ethnicity and SLEDAI. J. Autoimmun. 2019, 96, 147–157. [Google Scholar] [CrossRef] [PubMed]
  96. Scharer, C.D.; Blalock, E.L.; Mi, T.; Barwick, B.G.; Jenks, S.A.; Deguchi, T.; Cashman, K.S.; Neary, B.E.; Patterson, D.G.; Hicks, S.L.; et al. Epigenetic programming underpins B cell dysfunction in human SLE. Nat. Immunol. 2019, 20, 1071–1082. [Google Scholar] [CrossRef] [PubMed]
  97. Liu, L.; Hu, L.; Yang, L.; Jia, S.; Du, P.; Min, X.; Wu, J.; Wu, H.; Long, H.; Lu, Q.; et al. UHRF1 downregulation promotes T follicular helper cell differentiation by increasing BCL6 expression in SLE. Clin. Epigenetics 2021, 13, 31. [Google Scholar] [CrossRef]
  98. Dai, Y.; Zhang, L.; Hu, C.; Zhang, Y. Genome-wide analysis of histone H3 lysine 4 trimethylation by ChIP-chip in peripheral blood mononuclear cells of systemic lupus erythematosus patients. Clin. Exp. Rheumatol. 2010, 28, 158–168. [Google Scholar]
  99. Zhou, Y.; Qiu, X.; Luo, Y.; Yuan, J.; Li, Y.; Zhong, Q.; Zhao, M.; Lu, Q. Histone modifications and methyl-CpG-binding domain protein levels at the TNFSF7 (CD70) promoter in SLE CD4+ T cells. Lupus 2011, 20, 1365–1371. [Google Scholar] [CrossRef]
  100. Sullivan, K.E.; Suriano, A.; Dietzmann, K.; Lin, J.; Goldman, D.; Petri, M.A. The TNFalpha locus is altered in monocytes from patients with systemic lupus erythematosus. Clin. Immunol. 2007, 123, 74–81. [Google Scholar] [CrossRef]
  101. Apostolidis, S.A.; Rauen, T.; Hedrich, C.M.; Tsokos, G.C.; Crispin, J.C. Protein phosphatase 2A enables expression of interleukin 17 (IL-17) through chromatin remodeling. J. Biol. Chem. 2013, 288, 26775–26784. [Google Scholar] [CrossRef] [PubMed]
  102. Zhang, Z.; Song, L.; Maurer, K.; Petri, M.A.; Sullivan, K.E. Global H4 acetylation analysis by ChIP-chip in systemic lupus erythematosus monocytes. Genes Immun. 2010, 11, 124–133. [Google Scholar] [CrossRef] [PubMed]
  103. Zhang, Q.; Long, H.; Liao, J.; Zhao, M.; Liang, G.; Wu, X.; Zhang, P.; Ding, S.; Luo, S.; Lu, Q. Inhibited expression of hematopoietic progenitor kinase 1 associated with loss of jumonji domain containing 3 promoter binding contributes to autoimmunity in systemic lupus erythematosus. J. Autoimmun. 2011, 37, 180–189. [Google Scholar] [CrossRef]
  104. Hu, N.; Qiu, X.; Luo, Y.; Yuan, J.; Li, Y.; Lei, W.; Zhang, G.; Zhou, Y.; Su, Y.; Lu, Q. Abnormal histone modification patterns in lupus CD4+ T cells. J. Rheumatol. 2008, 35, 804–810. [Google Scholar] [PubMed]
  105. Zhao, M.; Wu, X.; Zhang, Q.; Luo, S.; Liang, G.; Su, Y.; Tan, Y.; Lu, Q. RFX1 regulates CD70 and CD11a expression in lupus T cells by recruiting the histone methyltransferase SUV39H1. Arthritis Res. Ther. 2010, 12, R227. [Google Scholar] [CrossRef]
  106. Hedrich, C.M.; Rauen, T.; Tsokos, G.C. cAMP-responsive element modulator (CREM)α protein signaling mediates epigenetic remodeling of the human interleukin-2 gene: Implications in systemic lupus erythematosus. J. Biol. Chem. 2011, 286, 43429–43436. [Google Scholar] [CrossRef]
  107. Mishra, N.; Brown, D.R.; Olorenshaw, I.M.; Kammer, G.M. Trichostatin A reverses skewed expression of CD154, interleukin-10, and interferon-gamma gene and protein expression in lupus T cells. Proc. Natl. Acad. Sci. USA 2001, 98, 2628–2633. [Google Scholar] [CrossRef]
  108. Liu, Y.; Liao, J.; Zhao, M.; Wu, H.; Yung, S.; Chan, T.M.; Yoshimura, A.; Lu, Q. Increased expression of TLR2 in CD4+ T cells from SLE patients enhances immune reactivity and promotes IL-17 expression through histone modifications. Eur. J. Immunol. 2015, 45, 2683–2693. [Google Scholar] [CrossRef]
  109. Zhao, H.; Wang, L.; Luo, H.; Li, Q.Z.; Zuo, X. TNFAIP3 downregulation mediated by histone modification contributes to T-cell dysfunction in systemic lupus erythematosus. Rheumatology 2017, 56, 835–843. [Google Scholar] [CrossRef]
  110. Ding, S.; Zhang, Q.; Luo, S.; Gao, L.; Huang, J.; Lu, J.; Chen, J.; Zeng, Q.; Guo, A.; Zeng, J.; et al. BCL-6 suppresses miR-142-3p/5p expression in SLE CD4+ T cells by modulating histone methylation and acetylation of the miR-142 promoter. Cell. Mol. Immunol. 2020, 17, 474–482. [Google Scholar] [CrossRef]
  111. Lee, S.; Nakayamada, S.; Kubo, S.; Yamagata, K.; Yoshinari, H.; Tanaka, Y. Interleukin-23 drives expansion of Thelper 17 cells through epigenetic regulation by signal transducer and activators of transcription 3 in lupus patients. Rheumatology 2020, 59, 3058–3069. [Google Scholar] [CrossRef]
  112. Ramanujan, S.A.; Cravens, E.N.; Krishfield, S.M.; Kyttaris, V.C.; Moulton, V.R. Estrogen-Induced hsa-miR-10b-5p Is Elevated in T Cells From Patients With Systemic Lupus Erythematosus and Down-Regulates Serine/Arginine-Rich Splicing Factor 1. Arthritis Rheumatol. 2021, 73, 2052–2058. [Google Scholar] [CrossRef]
  113. Moulton, V.R.; Grammatikos, A.P.; Fitzgerald, L.M.; Tsokos, G.C. Splicing factor SF2/ASF rescues IL-2 production in T cells from systemic lupus erythematosus patients by activating IL-2 transcription. Proc. Natl. Acad. Sci. USA 2013, 110, 1845–1850. [Google Scholar] [CrossRef]
  114. Katsuyama, T.; Li, H.; Comte, D.; Tsokos, G.C.; Moulton, V.R. Splicing factor SRSF1 controls T cell hyperactivity and systemic autoimmunity. J. Clin. Investig. 2019, 129, 5411–5423. [Google Scholar] [CrossRef]
  115. Xu, L.; Wang, L.; Shi, Y.; Deng, Y.; Oates, J.C.; Kamen, D.L.; Gilkeson, G.S.; Wang, F.; Zhang, M.; Tan, W.; et al. Up-Regulated Interleukin-10 Induced by E2F Transcription Factor 2-MicroRNA-17-5p Circuitry in Extrafollicular Effector B Cells Contributes to Autoantibody Production in Systemic Lupus Erythematosus. Arthritis Rheumatol. 2022, 74, 496–507. [Google Scholar] [CrossRef]
  116. Stagakis, E.; Bertsias, G.; Verginis, P.; Nakou, M.; Hatziapostolou, M.; Kritikos, H.; Iliopoulos, D.; Boumpas, D.T. Identification of novel microRNA signatures linked to human lupus disease activity and pathogenesis: miR-21 regulates aberrant T cell responses through regulation of PDCD4 expression. Ann. Rheum. Dis. 2011, 70, 1496–1506. [Google Scholar] [CrossRef]
  117. Sheedy, F.J.; Palsson-McDermott, E.; Hennessy, E.J.; Martin, C.; O’Leary, J.J.; Ruan, Q.; Johnson, D.S.; Chen, Y.; O’Neill, L.A. Negative regulation of TLR4 via targeting of the proinflammatory tumor suppressor PDCD4 by the microRNA miR-21. Nat. Immunol. 2010, 11, 141–147. [Google Scholar] [CrossRef]
  118. Hilliard, A.; Hilliard, B.; Zheng, S.J.; Sun, H.; Miwa, T.; Song, W.; Goke, R.; Chen, Y.H. Translational regulation of autoimmune inflammation and lymphoma genesis by programmed cell death 4. J. Immunol. 2006, 177, 8095–8102. [Google Scholar] [CrossRef]
  119. Bitomsky, N.; Bohm, M.; Klempnauer, K.H. Transformation suppressor protein Pdcd4 interferes with JNK-mediated phosphorylation of c-Jun and recruitment of the coactivator p300 by c-Jun. Oncogene 2004, 23, 7484–7493. [Google Scholar] [CrossRef] [PubMed]
  120. Tsytsykova, A.V.; Tsitsikov, E.N.; Geha, R.S. The CD40L promoter contains nuclear factor of activated T cells-binding motifs which require AP-1 binding for activation of transcription. J. Biol. Chem. 1996, 271, 3763–3770. [Google Scholar] [CrossRef] [PubMed]
  121. Xie, M.; Wang, J.; Gong, W.; Xu, H.; Pan, X.; Chen, Y.; Ru, S.; Wang, H.; Chen, X.; Zhao, Y.; et al. NF-κB-driven miR-34a impairs Treg/Th17 balance via targeting Foxp3. J. Autoimmun. 2019, 102, 96–113. [Google Scholar] [CrossRef]
  122. Xie, L.; Xu, J. Role of MiR-98 and Its Underlying Mechanisms in Systemic Lupus Erythematosus. J. Rheumatol. 2018, 45, 1397–1405. [Google Scholar] [CrossRef] [PubMed]
  123. Yang, M.; Yang, B.; Deng, D. Targeting of EIF4EBP1 by miR-99a-3p affects the functions of B lymphocytes via autophagy and aggravates SLE disease progression. J. Cell Mol. Med. 2021, 25, 10291–10305. [Google Scholar] [CrossRef]
  124. Zhao, X.; Tang, Y.; Qu, B.; Cui, H.; Wang, S.; Wang, L.; Luo, X.; Huang, X.; Li, J.; Chen, S.; et al. MicroRNA-125a contributes to elevated inflammatory chemokine RANTES levels via targeting KLF13 in systemic lupus erythematosus. Arthritis Rheum. 2010, 62, 3425–3435. [Google Scholar] [CrossRef] [PubMed]
  125. Wang, Y.; Liang, J.; Qin, H.; Ge, Y.; Du, J.; Lin, J.; Zhu, X.; Wang, J.; Xu, J. Elevated expression of miR-142-3p is related to the pro-inflammatory function of monocyte-derived dendritic cells in SLE. Arthritis Res. Ther. 2016, 18, 263. [Google Scholar] [CrossRef] [PubMed]
  126. Chan, E.K.; Satoh, M.; Pauley, K.M. Contrast in aberrant microRNA expression in systemic lupus erythematosus and rheumatoid arthritis: Is microRNA-146 all we need? Arthritis Rheum. 2009, 60, 912–915. [Google Scholar] [CrossRef] [PubMed]
  127. Tang, Y.; Luo, X.; Cui, H.; Ni, X.; Yuan, M.; Guo, Y.; Huang, X.; Zhou, H.; de Vries, N.; Tak, P.P.; et al. MicroRNA-146A contributes to abnormal activation of the type I interferon pathway in human lupus by targeting the key signaling proteins. Arthritis Rheum. 2009, 60, 1065–1075. [Google Scholar] [CrossRef]
  128. Lu, L.F.; Boldin, M.P.; Chaudhry, A.; Lin, L.L.; Taganov, K.D.; Hanada, T.; Yoshimura, A.; Baltimore, D.; Rudensky, A.Y. Function of miR-146a in controlling Treg cell-mediated regulation of Th1 responses. Cell 2010, 142, 914–929. [Google Scholar] [CrossRef]
  129. Luo, S.; Ding, S.; Liao, J.; Zhang, P.; Liu, Y.; Zhao, M.; Lu, Q. Excessive miR-152-3p Results in Increased BAFF Expression in SLE B-Cells by Inhibiting the KLF5 Expression. Front. Immunol. 2019, 10, 1127. [Google Scholar] [CrossRef]
  130. Tao, B.; Xiang, W.; Li, X.; He, C.; Chen, L.; Xia, X.; Peng, T.; Peng, L.; Yang, X.; Zhong, C. Regulation of Toll-like receptor-mediated inflammatory response by microRNA-152-3p-mediated demethylation of MyD88 in systemic lupus erythematosus. Inflamm. Res. Off. J. Eur. Histamine Res. Soc. 2021, 70, 285–296. [Google Scholar] [CrossRef]
  131. Miao, C.G.; Yang, Y.Y.; He, X.; Huang, C.; Huang, Y.; Zhang, L.; Lv, X.W.; Jin, Y.; Li, J. The emerging role of microRNAs in the pathogenesis of systemic lupus erythematosus. Cell Signal. 2013, 25, 1828–1836. [Google Scholar] [CrossRef]
  132. Lashine YA, Salah S, Aboelenein HR, Abdelaziz AI: Correcting the expression of miRNA-155 represses PP2Ac and enhances the release of IL-2 in PBMCs of juvenile SLE patients. Lupus 2015, 24, 240–247. [CrossRef]
  133. Smith, S.; Fernando, T.; Wu, P.W.; Seo, J.; Gabhann, J.N.; Piskareva, O.; McCarthy, E.; Howard, D.; O’Connell, P.; Conway, R.; et al. MicroRNA-302d targets IRF9 to regulate the IFN-induced gene expression in SLE. J. Autoimmun. 2017, 79, 105–111. [Google Scholar] [CrossRef]
  134. Geng, L.; Tang, X.; Zhou, K.; Wang, D.; Wang, S.; Yao, G.; Chen, W.; Gao, X.; Chen, W.; Shi, S.; et al. MicroRNA-663 induces immune dysregulation by inhibiting TGF-β1 production in bone marrow-derived mesenchymal stem cells in patients with systemic lupus erythematosus. Cell. Mol. Immunol. 2019, 16, 260–274. [Google Scholar] [CrossRef]
  135. Yang, B.; Huang, X.; Xu, S.; Li, L.; Wu, W.; Dai, Y.; Ge, M.X.; Yuan, L.; Cao, W.; Yang, M.; et al. Decreased miR-4512 Levels in Monocytes and Macrophages of Individuals With Systemic Lupus Erythematosus Contribute to Innate Immune Activation and Neutrsophil NETosis by Targeting TLR4 and CXCL2. Front. Immunol. 2021, 12, 756825. [Google Scholar] [CrossRef]
  136. Nemeth, K.; Bayraktar, R.; Ferracin, M.; Calin, G.A. Non-coding RNAs in disease: From mechanisms to therapeutics. Nat. Rev. Genet. 2023. [Google Scholar] [CrossRef]
  137. Liu, Q.; Deng, Y.; Li, C.; Xie, H.; Liu, Q.; Ming, S.; Wu, D.; Luo, F. LncRNA GAS5 suppresses CD4+ T cell activation by upregulating E4BP4 via inhibiting miR-92a-3p in systemic lupus erythematosus. Immunol. Lett. 2020, 227, 41–47. [Google Scholar] [CrossRef]
  138. Zhang, F.; Wu, L.; Qian, J.; Qu, B.; Xia, S.; La, T.; Wu, Y.; Ma, J.; Zeng, J.; Guo, Q.; et al. Identification of the long noncoding RNA NEAT1 as a novel inflammatory regulator acting through MAPK pathway in human lupus. J. Autoimmun. 2016, 75, 96–104. [Google Scholar] [CrossRef]
  139. Gao, F.; Tan, Y.; Luo, H. MALAT1 is involved in type I IFNs-mediated systemic lupus erythematosus by up-regulating OAS2, OAS3, and OASL. Braz. J. Med. Biol. Res. Rev. Bras. Pesqui. Medicas E Biol. 2020, 53, e9292. [Google Scholar] [CrossRef]
Figure 1. Genetic factors, environmental factors, and dysregurated epigenetic mechanisms, such as DNA methylation, histone modifications, and miRNA expression, induce aberrant immune systems, including adaptive immunity and innate immunity, resulting in the development of SLE. SLE: systemic lupus erythematosus; miRNA: microRNA; Treg: regulatory T cells; Tfh: T follicular helper cells; Tph: T peripheral helper cells; ABCs: age-associated B cells; TLR: Toll-like receptor; IRF: interferon regulatory factor; RIG-I: retinoic acid inducible gene-I; MDA5: melanoma differentiation-associated gene 5; MAVS: mitochondrial antiviral signaling; cGAS: cyclic GMP-AMP synthase; STING: stimulator of interferon genes; IFN: interferon.
Figure 1. Genetic factors, environmental factors, and dysregurated epigenetic mechanisms, such as DNA methylation, histone modifications, and miRNA expression, induce aberrant immune systems, including adaptive immunity and innate immunity, resulting in the development of SLE. SLE: systemic lupus erythematosus; miRNA: microRNA; Treg: regulatory T cells; Tfh: T follicular helper cells; Tph: T peripheral helper cells; ABCs: age-associated B cells; TLR: Toll-like receptor; IRF: interferon regulatory factor; RIG-I: retinoic acid inducible gene-I; MDA5: melanoma differentiation-associated gene 5; MAVS: mitochondrial antiviral signaling; cGAS: cyclic GMP-AMP synthase; STING: stimulator of interferon genes; IFN: interferon.
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Araki, Y.; Mimura, T. Epigenetic Dysregulation in the Pathogenesis of Systemic Lupus Erythematosus. Int. J. Mol. Sci. 2024, 25, 1019. https://doi.org/10.3390/ijms25021019

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Araki Y, Mimura T. Epigenetic Dysregulation in the Pathogenesis of Systemic Lupus Erythematosus. International Journal of Molecular Sciences. 2024; 25(2):1019. https://doi.org/10.3390/ijms25021019

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Araki, Yasuto, and Toshihide Mimura. 2024. "Epigenetic Dysregulation in the Pathogenesis of Systemic Lupus Erythematosus" International Journal of Molecular Sciences 25, no. 2: 1019. https://doi.org/10.3390/ijms25021019

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