Expression of human beta-defensin 2 in human nasal mucosa.

Human beta-defensin (HBD)-2, 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 HBD-2 in the human sinonasal tract, we conducted this study to investigate the expression of the HBD-2 mRNA gene by the reverse transcription polymerase chain reaction (RT-PCR) and localization of HBD-2 peptide by immunohistochemistry in human nasal inferior turbinates and nasal polyps. RT-PCR showed significantly higher expression of HBD-2 mRNA in nasal polyps than in inferior turbinates. Using immunohistochemistry, HBD-2 peptide was predominantly localized in surface epithelial cells. Thus, it is feasible that HBD-2 is expressed in nasal mucosa and is upregulated in a condition of chronic inflammation.