Impaired neutrophil directional chemotactic accuracy in chronic periodontitis patients

AIM: To investigate the chemotactic accuracy of peripheral blood neutrophils from patients with chronic periodontitis compared with matched healthy controls, pre- and post- non-surgical periodontal therapy.

MATERIAL & METHODS: Neutrophils were isolated from patients and controls (n=18) by density centrifugation. Using the Insall chamber and video microscopy, neutrophils were analysed for directional chemotaxis towards N-formyl-methyionyl leucyl phenylalanine (fMLP (10 nM), or CXCL8 (200 ng/ml). Circular statistics were utilised for the analysis of cell movement.

RESULTS: Prior to treatment neutrophils from chronic periodontitis patients had significantly reduced speed, velocity and chemotactic accuracy compared to healthy controls for both chemoattractants. Following periodontal treatment patient neutrophils continued to display reduced speed in response to both chemoattractants. However velocity and accuracy were normalized for the weak chemoattractant CXCL8 while they remained significantly reduced for fMLP.

CONCLUSIONS: Chronic periodontitis is associated with reduced neutrophil chemotaxis and this is only partially restored by successful treatment. Dysfunctional neutrophil chemotaxis may predispose periodontitis patients to their disease by increasing tissue transit times, thus exacerbating neutrophil-mediated collateral host tissue damage.