Toll-like receptor expression in the human nasopharyngeal tonsil (adenoid) and palantine tonsils: a preliminary report.
OBJECTIVE
The Waldeyer's ring, comprised of the nasopharyngeal tonsil (adenoid), the paired tubal tonsils, the paired palantine tonsils, and the lingual tonsil, is arranged in a circular orientation around the wall of the throat. This orientation allows direct contact between the tissues of the Waldeyer's ring and inhaled or ingested material, which may contain potential antigenic substances. Previous studies involving the tissues of the Waldeyer's ring have been focused on the adaptive immune system, with little consideration toward the innate immune system. Since studies have demonstrated that the adenoids and tonsils are capable of producing proinflammatory cytokines, we postulate that toll-like receptors (TLRs), which recognize components of pathogenic organisms, may be involved in the immune response in these tissues. TLRs are innate pattern recognition receptors, which produce proinflammatory cytokines and chemokines upon ligation. In this pilot study, we address expression of TLRs, which are vital components of the innate immune system, in adenoid and tonsil tissue.


METHODS
To determine whether TLRs are expressed in the human adenoid and palantine tonsils, we utilized endpoint RT-PCR and real time RT-PCR. Endpoint PCR was performed on all tissue obtained from adenotonsillectomy patients. Real time RT-PCR was performed only on adenoid tissue.


RESULTS
All of the ten TLRs examined are expressed in the adenoid and tonsil tissue with varying band intensities. TLR3, TLR7, TLR8, and TLR9 expression is highly variable between patients.


CONCLUSIONS
TLRs are expressed in human adenoid and tonsil tissue, and may play a vital role in the immunological outcomes of these tissues.
Lesmeister
Margaret J
MJ
Department of Molecular Microbiology and Immunology, University of Missouri-Columbia, School of Medicine, 1 Hospital Drive, M616 Medical Sciences Building, Columbia, MO 65212, USA.
Bothwell
Marcella R
MR
Misfeldt
Michael L
ML
D000234:Adenoids / Q000276:immunology*; D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D004587:Electrophoresis, Agar Gel; D006801:Humans; D007113:Immunity, Innate / Q000276:immunology; D007223:Infant; D018836:Inflammation Mediators / Q000032:analysis; D014066:Palatine Tonsil / Q000276:immunology*; D010865:Pilot Projects; D012313:RNA / Q000032:analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D051194:Toll-Like Receptor 1 / Q000032:analysis; D051195:Toll-Like Receptor 2 / Q000032:analysis; D051196:Toll-Like Receptor 3 / Q000032:analysis; D051197:Toll-Like Receptor 4 / Q000032:analysis; D051199:Toll-Like Receptor 7 / Q000032:analysis; D051200:Toll-Like Receptor 8 / Q000032:analysis; D051217:Toll-Like Receptor 9 / Q000032:analysis; D051193:Toll-Like Receptors / Q000032:analysis*
D018836:Inflammation Mediators; D051194:Toll-Like Receptor 1; D051195:Toll-Like Receptor 2; D051196:Toll-Like Receptor 3; D051197:Toll-Like Receptor 4; D051199:Toll-Like Receptor 7; D051200:Toll-Like Receptor 8; D051217:Toll-Like Receptor 9; D051193:Toll-Like Receptors; D012313:RNA