Copyright
©The Author(s) 2016.
World J Hepatol. Nov 18, 2016; 8(32): 1354-1369
Published online Nov 18, 2016. doi: 10.4254/wjh.v8.i32.1354
Published online Nov 18, 2016. doi: 10.4254/wjh.v8.i32.1354
TLR subfamily | Members | Expression of cell population in the liver (protein level) | Location | Ligand (origin) | Signaling | Final product-effect |
TLR2 subfamily | TLR1/2 | NK cells, DCs (h) | Plasma membrane | Bacterial lipoproteins Triacylated lipopeptides | TIRAP-MyD88-NF-κB/AP-1/IRF5 pathway | Pro- and anti-inflammatory cytokines excluding type 1 IFNs; the apoptotic cascade via recruiting FADD leading to caspase-8 activation |
TLR2/6 | Hepatocytes, Kupffer cells, NK cells, B cells, activated T cells, DCs (m), biliary epithelial cells | Diacylated lipopeptides LPS of Gram-positive bacteria Fungal zymosan Mycoplasma lipopeptides | TIRAP-MyD88-NF-κB/AP-1 pathway | |||
TLR10 | Unknown | ND | ||||
TLR3 subfamily | TLR3 | Hepatocytes, LSECs, Kupffer cells, NK cells, NKT cells, activated T cells, cDCs (m), biliary epithelial cells | Endosome | Double-stranded RNA (viruses) | PI3K/TRIF-IRF3 pathway TRAM-TRIF-NF-κB pathway PI3K/TRIF-RIP1-NF-κB pathway | Production of type 1 IFNs; the apoptotic cascade via recruiting FADD leading to caspase 8 activation; DC maturation |
TLR4 subfamily | TLR41 | Hepatocytes, LSECs, Kupffer cells, NK cells, B cells, activated T cells, DCs (m), biliary epithelial cells, HSCs | Plasma membrane | LPS of Gram-negative bacteria; fusion protein (respiratory syncytial virus), envelope protein (mouse mammary-tumor virus); HMGB1, hyaluronan, HSP60, free fatty acids (endogenous ligands); HSP72 (cells during stress and injury) surfactant protein A; fibrinogen; fibronectin extra domain A | TIRAP-MyD88-NF-κB/AP-1 pathway TRAM-TRIF-NF-κB/IRF3 pathway | Pro- and anti-inflammatory cytokines excluding type 1 IFNs; the apoptotic cascade via recruiting FADD leading to caspase 8 activation; DC maturation; activating caspase-1 through adaptor molecule apoptosis associated speck-like protein2 |
TLR5 subfamily | TLR5 | Biliary epithelial cells | Plasma membrane | Flagellin protein (bacteria) | MyD88-NF-κB/IRF5 pathway | Pro- and anti-inflammatory cytokines excluding type 1 IFNs |
TLR9 subfamily | TLR7/8 | NK cells, B cells, DCs (h), DCs (m) | Endosome | Single-stranded RNA (viruses), double-stranded, shortinterfering RNA (siRNA) | MyD88 and endosomal acidification (maturation)-IRF7 pathway; MyD88- NF-κB pathway | High levels of type 1 IFN production in pDCs; proinflammatory cytokine production |
TLR9 | LSECs, Kupffer cells, NK cells, B in mDCs and macrophages | Imidazoquinoline CpG-containing viral or bacterial DNA Endogenous host-DNA |
- Citation: Kiziltas S. Toll-like receptors in pathophysiology of liver diseases. World J Hepatol 2016; 8(32): 1354-1369
- URL: https://www.wjgnet.com/1948-5182/full/v8/i32/1354.htm
- DOI: https://dx.doi.org/10.4254/wjh.v8.i32.1354