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The expression of human antimicrobial peptide LL-37 in the human nasal mucosa
1Department of Otolaryngology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
Background:
LL-37, an antimicrobial peptide, has been discovered to be produced by a number of epithelial cells. It is identified as a key element in the innate host defense mechanism. Because little is known about the expression of LL-37 in human sinonasal tract, we conducted this study to investigate the expression of LL-37 in human nasal mucosa.
Methods:
We investigated the expression of LL-37 gene by the reverse transcription polymerase chain reaction (RT-PCR) and localization of LL-37 peptide by immunohistochemistry in the inferior turbinate mucosa of 7 normal subjects and the nasal polyps of 12 patients with chronic paranasal sinusitis.
Results:
The transcripts of the LL-37 gene were detected in all human nasal tissues analyzed by RT-PCR. There is a significant increase of LL-37 mRNA expression in nasal polyps as compared with the normal nasal mucosa. Using immunohistochemistry, LL-37 peptide was localized in surface epithelial cells and submucosal glands.
Conclusions:
Our findings suggest that LL-37 is expressed by nasal mucosa and is upregulated during inflammation.
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