BACKGROUND: Epithelial cells can be called the first line of a defense barrier to microorganisms by the innate immune system. The antimicrobial peptides are the major participants of this system. Cathelicidins are a family of peptides thought to provide an innate defensive barrier against a variety of potential microbial pathogens.
OBJECTIVES: To evaluate the expression of the cathelicidin in recurrent throat infection.
PATIENTS AND METHODS: Reverse transcriptase-polymerase chain reaction (RT-PCR) and immunohistochemical staining were performed for 10 palatine tonsil tissues with hypertrophy and 10 palatine tonsil tissues with recurrent throat infection.
RESULTS: Cathelicidin mRNA transcripts were detected in recurrent throat infection. The expression levels of cathelicidin mRNA in recurrent throat infection was significantly higher compared with those in hypertrophic tonsils. Cathelicidin protein was localized on the tonsillar surface epithelium and inflammatory cells in the tonsillar crypt of recurrent throat infection patients.
CONCLUSION: These results suggest that cathelicidin is one of antimicrobial peptides in the human palatine tonsils, and that cathelicidin may also play an important role in innate host defense of human tonsils.