Although sharing a similar structure, genomic localization, and involvement in RNA sensing, TLR7 and TLR8 are found in distinct immune cells (Hornung et al. 2002). This selective expression correlates with distinct biological functionality and production of type I IFNs (Gorden et al. 2005; Cervantes et al. 2011).
The initial observations that TLR8-deficient mice did not show any defect in nucleic acid detection, due to a lack of response to imidazoquinolines and RNA (Heil et al. 2004; Jurk et al. 2002), lead to a relative lack of interest in this particular endosomal TLR. Very recently it has been reported that overexpression of mTLR8 is required for the activation of transcription factor NF-κB and the production of TNF-α (Li et al. 2016). These results demonstrate that mTLR8 is indeed functional and does play a role in the activation of innate immune responses.
Structural Features of the TLR8 Ligand Recognition Domain
KeywordsCholesterol Hepatitis Leukemia Tuberculosis Bacillus
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