Table 3.
Summary of relevant microRNAs, target genes and target gene functions in immune cells and their putative regulatory roles in periodontal tissues
| Immune cells | miRNAs | miRNA in diseased tissues | Target genes | Target gene function in immune cells | Putative regulatory role of the miRNA in periodontal tissues | Ref. |
|---|---|---|---|---|---|---|
| Neutrophil | miR-9 | Up | NF-κ B1 | NF-κB family member | Feedback regulation of NF-κB pathway | 36 |
| miR-17 | Up | ICAM-1 | Endothelial adhesion molecule | Neutrophil adhesion to endothelial cells | 26 | |
| miR-34 | Up | Dock8 | Rho family member | Neutrophil emigration | 30 | |
| miR-155 | Up | FGD4, Rac1 | Rho family member | Neutrophil emigration | 30 | |
| SHIP-1 | Phosphoinositide lipid phosphatase | IL-8 mRNA stability | 28, 29 | |||
| miR-223 | Up | CXCL2, CCL3, IL-6 | Chemoattractants | Leukocyte chemotaxis | 32 | |
| NLRP3 | Inflammasome | Processing of inflammatory cytokines and pyroptosis | 34 | |||
| miR-31 | Down | E-selectin | Endothelial adhesion molecule | Neutrophil adhesion to endothelial cells | 26 | |
| miR-451 | Down | CPNE3, Rab5a, 14-3-3 | Binding proteins | Neutrophil chemotaxis | 31 | |
| Macrophage | miR-21 | Up | STAT3 | Transcription factor in inflammation | Prevent PGE-mediated M2 generation | 63 |
| miR-24 | Up | PKCα, CD163, CD206 | Components of pattern recognition receptor (PRR) signalling | Inhibit NF-κB activation | 42 | |
| P110δ | Kinase in class IAPI3 signalling | Promote M2 phenotype | 64 | |||
| miR-29b | Up | IL-6Rα, IFI30 | Components of cytokine signalling | Fine-tuning host response | 43, 44 | |
| miR-30 | Up | PKCα, CD163, CD206 | Components of PRR signalling | Inhibit NF-κB activation | 42 | |
| miR-125a | Up | KLF13 | Transcription factor in T cell activation and inflammation | Suppress classical but promote alternative activation of macrophage | 62 | |
| miR-125b | Up | IRF4 | Member of interferon response factor family | Enhance M1 phenotype | 59, 60 | |
| miR-142 | Up | PKCα, CD163, CD206 | Components of PRR signalling | Inhibit NF-κB activation | 42 | |
| miR-146 | Up | TRAF6, IRAK1, IRAK2 | Regulatory molecules in TLR/NF-κB pathway | Feedback regulation of inflammation | 48, 49 | |
| miR-155 | Up | MAP3K10 | Inflammatory pathway-related kinase | Endocytosis function | 51 | |
| SOSC1 | Negative regulator of type IFN signalling | Macrophage sensitivity and tolerance | 52, 53 | |||
| BCL6 | Transcription factor counter-regulating NF-κB activity | Enhance inflammation | 54 | |||
| IL13Ra1 | Component of the type II IL-4 receptor | Promote M1 phenotype | 56 | |||
| SMAD2 | Signalling molecule of TGF-β pathway | Regulation of macrophage polarization | 57, 58 | |||
| Let-7f | Up | SOCS4, TSP-1 | Regulators of inflammation | Regulate proinflammatory macrophage activity | 43, 44 | |
| Let-7 | Up | C/EB-d | Transcription factor in inflammatory response | Promote M2 phenotype | 61 | |
| Dendritic cells | miR-24 | Up | PKCα, CD14, TLR4, MD-1 | Components of PRR signalling | Inhibit NF-κB activation | 82 |
| miR-30 | Up | PKCα, CD14, TLR4, MD-1 | Components of PRR signalling | Inhibit NF-κB activation | 82 | |
| miR-126 | Up | TSC-1 | Negative regulator of mTOR | Survival and function of plasmacytoid DC | 79 | |
| miR-142 | Up | PKCα, CD14, TLR4, MD-1 | Components of PRR signalling | Inhibit NF-κB activation | 82 | |
| miR-155 | Up | c-FOS, PU.1 | Transcription factors | DC maturation | 73 | |
| SOCS-1 | Negative regulator of IL-2 signalling | DC maturation and pathogen binding | 71 | |||
| let-7 | Up | SOCS-1 | Negative regulator of IL-2 signalling | Enhance a proinflammatory phenotype of mature DC | 74, 75 | |
| T cells | miR-17 | Up | IKZF4 | Member of the Ikaros family transcription factors | Promote Th17 phenotype | 95 |
| TGFβRII | TGF-β signalling | Enhance Th1 differentiation and prevent Treg response | 104 | |||
| CREB1 | Transcription factor regulating FoxP3 expression | Enhance Th1 differentiation and prevent Treg response | 104 | |||
| miR-19 | Up | PTEN | Negative regulation of PI3K-AKT-mTOR axis | Enhance Th17 polarization | 95 | |
| miR-24 | Up | FoxP3 | Lineage-specific factor of Treg cells | Inhibit Treg differentiation | 113, 114 | |
| miR-29 | Up | TBX21EOMES | Transcription factors for INF-γ | Inhibit Th1 differentiation | 103 | |
| miR-31 | Up | FoxP3 | Lineage-specific factor of Treg cells | Inhibit Treg differentiation | 113, 114 | |
| miR-125a | Up | STAT3, IL-13, INF-γ | Critical factors for effector lineages | Inhibit Treg differentiation | 115 | |
| miR-146 | Up | TRAF6, IRAK1 | Regulatory molecules in TLR/NF-κB pathway | Feedback regulation of NF-κB signalling in T cells | 92, 96 | |
| STAT1 | Transcription factor for INF-γ | Suppress Th1 response | 112 | |||
| miR-155 | Up | SOCS-1 | Inhibitor of STAT5 signalling | Maintain Treg homeostasis and function | 104 | |
| INF-γRA | Cytokine receptor | Inhibit Th2 differentiation | 105 | |||
| miR-181 | Up | SHP2, PTPN22, DUSPS5, DUSPS6 | Phosphatases | Elevate steady-state levels of phosphorylated interaction and reduce T cell receptor signalling threshold | 89, 90 | |
| miR-301 | Up | PIAS3 | Inhibitor of STAT3 pathway Transcription factors for plasma cell differentiation | Promote Th17 response | 119 | |
| let-7 | Up | IL-13 | Cytokine | Inhibit Th2 differentiation | 106 | |
| miR-214 | Down | PTEN | Negative regulator of AKT signalling | Enhance Th17 polarization | 94 | |
| B cells | miR-125b | Up | Blimp1, IRF4 | Transcription factors for plasma cell differentiation | Promote B cell diversification in GC | 123 |
| miR-148 | Up | PTEN, Bim | Proapoptotic factors in B cells | Promote plasmablast survival | 125 | |
| Bach2, Mitf | Transcription factors for plasma cell differentiation | Promote plasma cell differentiation | 124 | |||
| miR-155 | Up | AID | A potent DNA mutator | Antibody affinity maturation | 127 | |
| miR-181 | Up | AID | A potent DNA mutator | Antibody affinity maturation | 128 |