T and B Cells in Periodontal Disease: New Functions in A Complex Scenario.

Periodontal disease is characterised by a dense inflammatory infiltrate in the connective tissue. When the resolution is not achieved, the activation of T and B cells is crucial in controlling chronic inflammation through constitutive cytokine secretion and modulation of osteoclastogenesis. The present narrative review aims to overview the recent findings of the importance of T and B cell subsets, as well as their cytokine expression, in the pathogenesis of the periodontal disease. T regulatory (Treg), CD8+ T, and tissue-resident γδ T cells are important to the maintenance of gingival homeostasis. In inflamed gingiva, however, the secretion of IL-17 and secreted osteoclastogenic factor of activated T cells (SOFAT) by activated T cells is crucial to induce osteoclastogenesis via RANKL activation. Moreover, the capacity of mucosal-associated invariant T cells (MAIT cells) to produce cytokines, such as IFN-γ, TNF-α, and IL-17, might indicate a critical role of such cells in the disease pathogenesis. Regarding B cells, low levels of memory B cells in clinically healthy periodontium seem to be important to avoid bone loss due to the subclinical inflammation that occurs. On the other hand, they can exacerbate alveolar bone loss in a receptor activator of nuclear factor kappa-B ligand (RANKL)-dependent manner and affect the severity of periodontitis. In conclusion, several new functions have been discovered and added to the complex knowledge about T and B cells, such as possible new functions for Tregs, the role of SOFAT, and MAIT cells, as well as B cells activating RANKL. The activation of distinct T and B cell subtypes is decisive in defining whether the inflammatory lesion will stabilise as chronic gingivitis or will progress to a tissue destructive periodontitis.

Clinical, immunological and microbial gingival profile of juvenile systemic lupus erythematosus patients.

Periodontal disease has been associated with rheumatic diseases; however, few studies have evaluated the association with systemic lupus erythematosus (SLE), and its impact on the local inflammatory and microbial profiles. Therefore, this study evaluated the levels of several cytokines in gingival crevicular fluid (GCF) and serum from juvenile SLE (jSLE) patients with gingival inflammation, compared with controls. In addition, we assessed their subgingival microbial profile. Thirty jSLE patients and 29 systemically healthy individuals were recruited. Participants were rheumatologically and periodontally examined, and GCF, serum and intrasulcular biofilm were collected. Cytokines were analysed by bead-based multiplex assays and the bacterial profile by checkerboard DNA-DNA hybridization. jSLE patients presented higher percentages of dental plaque and bleeding than controls, as well as increased mean probing depth and attachment loss. After adjustment for multiple comparisons, GCF levels of interleukin (IL)-1ß, IL-8, granulocyte colony-stimulating factor (G-CSF), interferon-γ and monocyte chemoattractant protein-1 were significantly higher, whereas the levels of granulocyte-macrophage colony-stimulating factor were significantly lower in jSLE patients. In serum, G-CSF levels tended to be higher in jSLE patients (adjusted p-value = 0.06). Intrasulcular counts of Aggregatibacter actinomycetemcomitans were significantly higher in jSLE patients as compared with controls. We conclude that patients with jSLE present a worse periodontal condition associated with altered levels of pro-inflammatory cytokines in GCF and increased counts of A. actinomycetemcomitans in the intrasulcular biofilm.

Oral-gut connection: one step closer to an integrated view of the gastrointestinal tract?

Although an enrichment of orally derived bacteria is reported in the gut microbiota of patients with several diseases, it is mostly unknown whether oral bacteria can colonize and induce intestinal inflammation. In a recent paper in Science, Atarashi et al.1 from Kenya Honda's laboratory show that a subset of orally derived bacteria colonizes and persists in the gut, leading to activation of the intestinal immune system and subsequent chronic inflammation in a susceptible host. The impact of oral health status as a potential contributor to inflammatory diseases at distal sites of the body deserves consideration.

Activity of inflammatory bowel disease influences the expression of cytokines in gingival tissue.

This study assessed the cytokine expression in gingival and intestinal tissues from periodontitis patients with inflammatory bowel disease (IBD) and evaluated if IBD activity is a covariate to the amount of gingival cytokines. Paired gingival and intestinal tissues were collected from 21 patients and homogenised using a cell disruptor. Cytokine expression (IL-1ß, IL-4, IL-6, IL-10, IL-21, IL-22, IL-23, IL-25, IL-31, IL-33, IL-17A, IL-17F, IFN-γ, sCD40L, and TNF-α) was evaluated using bead-based multiplex technology. An inflammation score was developed using the intestinal cytokines that showed good accuracy to discriminate IBD active patients from those in remission and then a similar score was applied to gingival tissue. IL-4, IL-10 and IL-21 expressions were significantly increased in gingival tissue from patients with an active disease as compared to those with a disease in remission. The inflammation score (mean value of IL-1ß, IL-6, IL-21, and sCD40L) was significantly higher in gingival tissue from patients with IBD activity. There was a significant correlation between gingival and intestinal inflammation scores (rho=0.548; P=0.01). Significantly higher IL-23 and IFN-γ levels and lower IL-31 and TNF-α levels were observed in gingival tissues than in intestinal ones. Activity of inflammatory bowel disease influenced the cytokine expression in gingival tissue.

Serum creatinine and alkaline phosphatase levels are associated with severe chronic periodontitis.

BACKGROUND AND OBJECTIVE: Periodontitis may alter systemic homeostasis and influence creatinine and alkaline phosphatase levels. Therefore, the aim of this study was to evaluate the relationship between severe chronic periodontitis and serum creatinine and alkaline phosphatase levels. MATERIAL AND METHODS: One hundred patients were evaluated, 66 with severe chronic periodontitis (test group) and 34 periodontally healthy controls (control group). Medical, demographic and periodontal parameters were registered. Blood sample was collected after an overnight fast and serum creatinine and alkaline phosphatase levels were determined. RESULTS: There were significant differences between test and control groups in ethnicity, gender and educational level (p < 0.05). Patients with periodontitis showed a lower mean creatinine level (p < 0.05) and higher mean alkaline phosphatase level (p < 0.001) than the control group. There were significant correlations between periodontal parameters and serum creatinine and alkaline phosphatase levels. CONCLUSION: Severe chronic periodontitis was associated to lower creatinine and higher alkaline phosphatase levels.