Send to

Choose Destination
J Dent Res. 2006 Jan;85(1):49-53.

Trigeminal nociceptors express TLR-4 and CD14: a mechanism for pain due to infection.

Author information

Department of Endodontics, UTHSCSA, 7703 Floyd Curl Drive, San Antonio, TX 78229, USA.


Although certain bacterial species appear to be risk factors for pain due to odontogenic infections, comparatively little is known about the potential mechanisms mediating this effect. In this study, we tested the hypothesis that trigeminal nociceptive neurons express the TLR4 or CD14 receptors, thus enabling sensory neurons to detect and respond to tissue levels of bacterial substances such as lipopolysaccharide (LPS). Immunohistochemical analyses of human and rat trigeminal neurons demonstrated that a capsaicin-sensitive subclass of nociceptors (defined by expression of TRPV1, a capsaicin receptor) expresses both TLR4 and CD14. Moreover, human dental pulp collected from patients with caries lesions demonstrated co-localization of TLR4 and CD14, with markers of peripheral sensory neurons. Collectively, these studies indicate that the capsaicin-sensitive subclass of trigeminal nociceptors expresses TLR4 and CD14. These results indicate that pain due to bacterial infections may result, in part, from direct activation of nociceptors by bacterial products such as LPS.

[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Atypon Icon for PubMed Central
Loading ...
Support Center