The novel human beta‐defensin‐3 is widely expressed in oral tissues

Abstract

The purpose of this study was to investigate the expression of human beta‐defensins (hBD), especially of the recently discovered hBD‐3, in oral tissues by reverse‐transcription polymerase chain reaction (RT‐PCR). Primary oral keratinocytes ( n = 3) and fibroblasts ( n = 3), 64 non‐inflamed and 40 inflamed oral tissue samples, and 10 samples of salivary glands, were examined. The transcripts for hBD‐3 (61/64), as well as for hBD‐1 (64/64) and hBD‐2 (54/64), were found to be widely expressed in non‐inflamed oral tissues. In contrast, only 23, 22 and 24 of the 40 inflamed tissues showed detectable hBD‐1, ‐2 and ‐3 transcripts, respectively. In salivary glands, mRNA expression was constitutive for hBD‐1, frequent for hBD‐2 (9/10), and infrequent for hBD‐3 (4/10). Oral keratinocytes, but not fibroblasts, contained transcripts for all beta‐defensins, suggesting that the novel hBD‐3 is also produced in the epithelial compartment of oral tissues. The results indicate an important role for the novel hBD‐3, as well as for hBD‐1 and hBD‐2, in the innate oral epithelial host defense.