Reduced human beta defensin 3 in individuals with periodontal disease.

The human beta defensin 3 (hBD3) is widely expressed in the oral cavity and exerts strong antibacterial and immunomodulatory activities. Hence, we hypothesized that hBD3 could play a protective role in the maintenance of periodontal homeostasis, and that it could be found in gingival crevicular fluid (GCF) of healthy individuals and those with periodontitis at levels correlating with the degree of periodontal health. By using an ELISA assay to quantify hBD3 in GCF, we demonstrated that the peptide is present at levels easily detectable in the majority of healthy individuals, but it is drastically reduced in GCF from those with periodontitis. Furthermore, hBD3 levels inversely correlate with the severity of the disease and the degree of colonization by combinations of bacterial species with elevated periodontopathogenic potential. Both genetic factors and host/bacterial proteases released in diseased sites may be responsible for the observed low/null hBD3 levels in GCF from individuals with periodontitis.