Impaired neutrophil directional chemotactic accuracy in chronic periodontitis patients

Abstract

AimTo investigate the chemotactic accuracy of peripheral blood neutrophils from patients with chronic periodontitis compared with matched healthy controls, before and after non-surgical periodontal therapy.Material & MethodsNeutrophils 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-methionyl-leucyl-phenylalanine [fMLP (10 nM), or CXCL8 (200 ng/ml)]. Circular statistics were utilized for the analysis of cell movement.ResultsPrior to treatment, neutrophils from patients with chronic periodontitis 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.ConclusionsChronic periodontitis is associated with reduced neutrophil chemotaxis, and this is only partially restored by successful treatment. Dysfunctional neutrophil chemotaxis may predispose patients with periodontitis to their disease by increasing tissue transit times, thus exacerbating neutrophil-mediated collateral host tissue damage.

Modulation of Neutrophil Extracellular Trap and Reactive Oxygen Species Release by Periodontal Bacteria

“…Neutrophils are the predominant immune cell in periodontitis (18), and the results presented here support the suggestion that their stimulation with periodontal bacteria promotes extracellular, intracellular, and superoxide ROS release; however, data indicate that this may be species specific. Indeed, some species consistently elicited higher levels of neutrophil ROS production, while other bacteria, such as P. gingivalis or S. sanguinis, were not found to significantly promote ROS release.…”

“…It has also been reported that neutrophil chemotaxis is compromised in patients with chronic periodontitis and that these patients' neutrophils produce the chemoattractant interleukin-8 in excess when stimulated, potentially creating distracted chemotaxis (31). Such processes may increase neutrophil tissue transit times and thereby potentially exacerbate ROS-mediated collateral tissue damage (18).…”

Filifactor alocis Promotes Neutrophil Degranulation and Chemotactic Activity

“…Neutrophil migration toward sites of infection is a key early event in the process of protection against pathogenic microorganisms, and in peri-odontal disease, neutrophils are recruited in high numbers into the gingival tissues and crevicular fluid to control and combat the bacterial infection (35). However, neutrophils from chronic periodontitis patients show dysfunctional chemotactic function which increases the cell transit time in the gingival connective tissue, promoting collateral tissue damage (36). Using a mouse chamber model, we recently showed that F. alocis infection resulted in rapid neutrophil infiltration to the site of infection (10).…”

Periodontal and inflammatory bowel diseases: Is there evidence for complex pathogenic interactions?

“…Previous studies from our group have shown that neutrophils from periodontitis patients are hyper-reactive and contribute to tissue destruction [3,19,20] . These neutrophils have also been shown to present a cytokine hyper-reactivity [21] and a dysfunctional chemotaxis [22] . When the resolution of inflammation is not achieved, antigen-presenting cells are activated by bacterial pro-ducts and interact with naïve T helper cells (Th0), driving their differentiation into several subsets, such as Th1, Th2, Th17, and Treg.…”