Oral Neutrophil Transcriptome Changes Result in a Pro-Survival Phenotype in Periodontal Diseases

Abstract

BackgroundPeriodontal diseases are inflammatory processes that occur following the influx of neutrophils into the periodontal tissues in response to the subgingival bacterial biofilm. Current literature suggests that while neutrophils are protective and prevent bacterial infections, they also appear to contribute to damage of the periodontal tissues. In the present study we compare the gene expression profile changes in neutrophils as they migrate from the circulation into the oral tissues in patients with chronic periodontits and matched healthy subjects. We hypothesized that oral neutrophils in periodontal disease patients will display a disease specific transcriptome that differs from the oral neutrophil of healthy subjects.MethodsVenous blood and oral rinse samples were obtained from healthy subjects and chronic periodontitis patients for neutrophil isolation. mRNA was isolated from the neutrophils, and gene expression microarray analysis was completed. Results were confirmed for specific genes of interest by qRT-PCR and Western Blot analysis.Results and DiscussionChronic periodontitis patients presented with increased recruitment of neutrophils to the oral cavity. Gene expression analysis revealed differences in the expression levels of genes from several biological pathways. Using hierarchical clustering analysis, we found that the apoptosis network was significantly altered in patients with chronic inflammation in the oral cavity, with up-regulation of pro-survival members of the Bcl-2 family and down-regulation of pro-apoptosis members in the same compartment. Additional functional analysis confirmed that the percentages of viable neutrophils are significantly increased in the oral cavity of chronic periodontitis patients.ConclusionsOral neutrophils from patients with periodontal disease displayed an altered transcriptome following migration into the oral tissues. This resulted in a pro-survival neutrophil phenotype in chronic periodontitis patients when compared with healthy subjects, resulting in a longer-lived neutrophil. This is likely to impact the severity and length of the inflammatory response in this oral disease.

Neutrophil transcriptional profile changes during transit from bone marrow to sites of inflammation

“…Consistent with our previous report, where neutrophils altered their transcriptome and phenotype as they transited from circulation into the oral cavity in humans, 58,59 we also observed pathways not traditionally associated with neutrophil biology such as cell-to-cell signaling and interaction, IL-17 signaling and regulation of T-cell activation to be enriched in murine blood when compared with BM and the peritoneum. A large number of genes commonly expressed in T cells can also be expressed by neutrophils.…”

Neutrophil Dysfunction and Host Susceptibility to Periodontal Inflammation: Current State of Knowledge

“…Furthermore, many crevicular PMNs are in advanced stages of NET formation [66]. Similarly, in oral rinses from periodontitis patients, there are more viable and fewer apoptotic PMNs, suggesting increased cell survival in disease [67]. Fig.…”

Neutrophils Increase Oral Squamous Cell Carcinoma Invasion through an Invadopodia-Dependent Pathway

“…All cell cultures and experiments were performed in DMEM supplemented with 10% FBS, 100 nmol/L nonessential amino acids (Sigma), penicillin, and streptomycin (100 mg/mL). Peripheral blood neutrophils were isolated and purified from healthy donors as described before (22). Neutrophil viability by Trypan blue exclusion after 24 hours of incubation with cancer cells was 64.2% (AE0.04%).…”