The interplay of lipopolysaccharide-binding protein and cytokines in periodontal health and disease.

AIM: Periodontal pathogenesis is characterized by Gram-negative bacteria activation of series of pro- and anti-inflammatory cytokines from host cells through the pathway of lipopolysaccharide (LPS), LPS-binding protein (LBP) and CD14. The present study investigated the expression profiles of interleukin (IL)-1beta and IL-10 in periodontal health and disease, and examined the effects of Escherichia coli LPS and LBP interaction on the expression of IL-1beta and IL-10 by human gingival fibroblasts (HGF).

MATERIAL AND METHODS: Gingival biopsies were collected from 44 subjects with chronic periodontitis and 15 periodontally healthy subjects. The expression of IL-1beta and IL-10 was detected by immunohistochemistry. The mRNA expression of IL-1beta and IL-10 in HGF was detected by RT-PCR with or without recombinant human LBP (rhLBP), while the peptides were analysed by an enzyme-linked immunosorbent assay.

RESULTS: IL-1beta was detected in both oral sulcular epithelia of healthy controls and periodontal pocket epithelia of patients. IL-10 was mainly expressed in the intercellular spaces of connective tissues. IL-1beta displayed a reverse pattern of expression levels with reference to IL-10, and a negative correlation existed between LBP and the ratio of IL-1beta/IL-10. rhLBP suppressed E. coli LPS-induced IL-1beta expression by HGF.

CONCLUSION: An appropriate interplay of LBP and cytokines may have a beneficial effect on innate host defence, thereby contributing to periodontal homeostasis.