Journal of Clinical Periodontology. The relationship between neutrophil numbers, Human Neutrophil Peptides 1-3 and Matrix Metalloproteinase 8 in Periodontal Disease. Wan-Chien Cheng , Fahd Saleh , Belkais Abuaisha Karim, Francis J. Hughes. (SUBMITTED AND AWAITING REVIEW)

Aim: to assess whether polymorphonuclear leucocyte (PMN) numbers are directly correlated with human neutrophil peptide 1,2,3 (HNP) concentrations or matrix metalloproteinase-8 (MMP8) in gingival crevicular fluid (GCF) and to investigate the relationship between salivary and GCF HNP and MMP8 concentrations.

Materials and Methods: A total of 35 saliva samples were collected from 35 participants (5 with aggressive periodontitis (AgP), 18 with chronic periodontitis (CP) and 12 with gingivitis or healthy (H/G)). GCF samples were collected using Durapore® filter strips from 3 sites with probing depth >5mm (DS) from each AgP and CP participant and 3 sites with probing depth ≤3mm (NS) from all participants. PMN numbers were determined using an automated cell counter and HNP and MMP8 concentrations were assessed by ELISA.

Results: PMN numbers significantly correlate with GCF HNP (R2=0.21) and MMP8 (R2=0.67) concentrations when analysed by site.  Intra and inter- group analysis revealed no correlation between salivary and GCF HNP or MMP8 concentrations. Salivary HNP concentration ≥ 3.65µg/ml was diagnostic of periodontitis with 100% sensitivity and 65% specificity. Salivary MMP8 concentration ≥ 264ng/ml was diagnostic of chronic periodontitis with 94% sensitivity and 100% specificity.

Conclusion: GCF HNP concentrations are not a surrogate marker for PMN numbers. Other complex factors may control their levels in GCF. GCF MMP8 concentrations moderately correlate with GCF PMN numbers possibly due to effect of the gingival environment on MMP8 production in the PMNs.  Salivary HNP and MMP8 concentrations are lower in health or gingivitis when compared to periodontitis and the difference cannot be attributed solely to GCF content.