From:  Epigenetic and metabolic reprogramming in autoimmune rheumatology: toward immune tolerance reprogramming

 Core cellular modules of the immune tolerance network.

Cell typeKey metabolic programKey epigenetic featuresFunctional outcomeReferences
Regulatory T cells (Tregs)Oxidative phosphorylation (OXPHOS); fatty-acid oxidation (FAO); high NAD+; AMPK-SIRT1 signalingFOXP3 CNS2 demethylation; repressive histone marks at effector lociMaintenance of immune suppression and tolerance stability[12, 37]
Regulatory B cells (Bregs)Balanced glycolysis/OXPHOS; low ROSBLIMP-1-dependent chromatin programSuppression of humoral autoimmunity and control of germinal-center responses[38, 39]
Tolerogenic dendritic cells (tolDCs)OXPHOS-dominant; IDO1-kynurenine pathwayReduced H3K27ac at costimulatory loci; tolerogenic enhancer landscapeInduction of Tregs and peripheral tolerance[4042]
M2-like macrophagesOXPHOS; low succinate; low HIF-1αRepressive chromatin at inflammatory gene lociTissue repair, anti-inflammatory signaling, and resolution of inflammation[4345]
Fibroblast-like synoviocytes (FLS)Increased glycolysis; altered mitochondrial/OXPHOS balance in inflammatory statesEpigenetic activation of inflammatory and tissue-remodeling programs, including EZH2- and non-coding RNA-associated regulationStromal activation, inflammatory mediator production, matrix remodeling, and persistence of synovial inflammation[4648]
Stromal & endothelial cellsOxidative tissue niche; retinoic acid and kynurenine productionRepressed adhesion molecule loci (ICAM1/VCAM1)Regulation of immune-cell trafficking and tissue-level equilibrium[49, 50]

AMPK: AMP-activated protein kinase; BLIMP-1: B lymphocyte-induced maturation protein 1; CNS2: conserved non-coding sequence 2; FOXP3: forkhead box P3; HIF-1α: hypoxia-inducible factor-1 alpha; ICAM1: intercellular adhesion molecule 1; IDO1: indoleamine 2,3-dioxygenase 1; ROS: reactive oxygen species; SIRT1: sirtuin 1.