Table 2.

Summary of epigenetic mechanisms involved in autoimmune diseases.

	DNA methylation
Systemic lupus eErithematosus	Global Hypomethylation of promoter region of genes:	References
	ITGAL	[23]
	CD40LG	[24]
	PRF1	[25]
	CD70	[26]
	IFGNR2	[27]
	MMP14	[27]
	LCN2	[27]
	Ribosomal RNA gene promoter (18S and 28S)	[27]
	e1B promoter of CD5 in resting B cells	[28]
Rheumatoid arthritis	Hypomethylation:
	CpG islands upstream of an L1 open-reading frame	[29]
	IL-6 promoter gene in monocytes	[30]
	Hypermethylation:
	Promoter of death receptor 3 (DR-3)	[31]
Type 1 diabetes	Global hypermethylation by altered metabolism of homocysteine	[32]
Multiple sclerosis	Hypomethylation of promoter region of peptidyl arginine deiminase type II (PAD2)	[33]
Systemic sclerosis	Hypermethylation of CpG islands in Fli1 promoter	[34]
	Histone modification
Systemic lupus erithematosus	Predisposition to apoptotic nucleosomes
	H3K4me3
	H4K8 triacetylation
	H3K27me3	[35]
	H2BK12ac
	Global acetylation of histone H3 and H4 in active CD4+ T cells	[36]
Rheumatoid arthritis	HDAC inhibitors:
	Block induction of MMPs	[37]
	Repress of ADAMTs enzymes
	Hyperacetylation of histones induces p16 and p21	[38]
Type 1 diabetes	Increase H3K9me2 in lymphocytes genes:
	CLTA4
	TGF-B
	NF-κB	[39]
	p38
	IL-6
	Hyperglcemia causes H3K4 and H3K9 methylation	[40]
Multiple sclerosis	Hyperacetylation of H3 promoter region in white matter	[41]
	miRNAs
Systemic lupus Erithematosus	Decreased expression:
	miR-146a	[42]
	miR-125a	[43]
	Upregulation:
	miR-21 and miR-148a	[44]
	miR-155	[45]
Rheumatoid arthritis	Overexpression:
	miR-155	[46]
	miR-203	[47]
	miR-146	[48]
	Decreased expression of miR-124	[49]
Multiple sclerosis	Upregulation:
	miR-326	[50]
	miR-34a	[51]
	miR-155	[51]
	Expression in Treg cells: miR-17-5p, miR-497, miR-193 and miR-126	[52]
	Disease Relapse: miR-18b and miR-599 Disease Remission: miR-96	[53]
	Brain-specific: miR-124	[54]
Type 1 diabetes	Overexpression of miRNA-510	[55]
	Decreased expression of miRNA-342 and miRNA-191	[55]
	Beta cell failure: miR-21, miR-34a, and miR-146a	[56]
Sjögren's syndrome	Overexpression: miR-547-3p and miR-168-3p	[57]
	Upregulated: miR-150 and miR-149	[57]