IL-35 may maintain homeostasis of the immune microenvironment in periodontitis

Interleukin-6, -17, and -35 levels in association with clinical status in stage III and stage IV periodontitis: a cross-sectional study

BACKGROUND

This study compared the concentrations of interleukin (IL)-6, IL-17, and IL-35 in the gingival crevicular fluid of periodontally healthy participants with individuals who had stage III and IV periodontitis.

METHODS

In total, 60 participants with stage III grade B-C (n = 12)-stage IV grade C (n = 18) periodontitis and 30 healthy controls were included in this cross-sectional study. Full-mouth clinical periodontal measurements were performed. Concentrations of IL-6, IL-17, and IL-35 were determined using enzyme-linked immunosorbent assays. Parametric/nonparametric methods, Pearson's/Spearman's correlation, and logistic regression methods were used for data analyses.

RESULTS

The periodontitis group exhibited significantly higher levels of IL-6, IL-17, and IL-35 compared with the healthy group (p < 0.001). IL-17 levels had a positive correlation with pocket depth (PD) (r = 0.395; p = 0.031) in the periodontitis group. IL-6, IL-17, and IL-35 levels were associated with periodontitis (odds ratio [OR] = 1.344, 95% confidence interval [CI] = 1.159-1.56; OR = 1.063, 95% CI = 1.025-1.102; OR = 1.261, 95% CI = 1.110-1.434, respectively) (p < 0.001, p = 0.001, p < 0.001, respectively). Full-mouth and sampling sites PD and clinical attachment loss (CAL) values were significantly higher in the periodontitis group than in the healthy group (p < 0.001).

CONCLUSIONS

This study revealed upregulated levels of IL-6, IL-17, and IL-35 in periodontitis patients compared to healthy individuals. IL-17 shows a correlation with increased PD. These findings suggest a potential association between these cytokines and severe and advanced periodontitis.

TRIAL REGISTRATION

The trial was registered in ClinicalTrials.gov with this identifier NCT05306860 on 24/01/2022.

IL-39 and IL-35 gingival crevicular fluid levels in diabetic patients with generalized periodontitis

OBJECTIVES

This research was performed to investigate if there is a role for IL-39 in immunopathogenesis of both systemically healthy and diabetic periodontitis patients. Additionally, to explore if we can consider IL-39 and IL-35 as biomarkers for periodontitis activity.

MATERIALS AND METHODS

A total of 38 periodontitis patients and 19 control volunteers were included in our study. The periodontitis patients were divided equally into (Group I), 19 patients with stage III grade C periodontitis with diabetes mellitus and (Group II), 19 patients with stage III grade B periodontitis and systemically healthy. Gingival crevicular fluid levels of each interleukin were measured pre- and postoperatively for all periodontitis patients as well as control subjects using ELISA.

RESULTS

Our study results showed that the highest level for IL-39 was in diabetic periodontitis patients that decreased significantly postoperatively. However, the highest level for IL-35 was revealed in control group while the lowest value was registered in diabetic periodontitis patients and statistically increased after periodontal treatment.

CONCLUSIONS

Based on the results of our research, both investigated biomarkers may have a potent role in pathogenesis of periodontitis.

CLINICAL RELEVANCE

We could consider both interleukins as accurate diagnostic markers for periodontitis patients, regardless of diabetes mellitus association, as well as promising markers that can aid in the prevention and treatment of periodontitis patients worldwide.

Estimating the salivary levels of IL-35 in smokers with periodontitis: A cross sectional study

Background

A refined network and integrated host immune response to bacteria are formed by anti-inflammatory cytokines and the cells that they are associated to IL-35 has been recognized as having strong suppressive activity in chronic inflammatory diseases, together with IL-10 and TGF-β. It is believed that inflammatory diseases like periodontitis trigger the inducible Treg population to express IL-35, expanding regulatory responses by increasing infection.

Aim

The objective is to estimate and compare the salivary IL-35 levels in Periodontally healthy subjects, smokers and non-smokers with Periodontitis in order to educate on the consequences of periodontal health among the diseased patients.

Materials and Methods

Totally 42 subjects were included and they were categorized into Group 1 (n = 14) as Periodontally healthy subjects, Group 2 (n = 14) as systemically healthy non-Smokers with periodontitis and Group 3 (n = 14) as systemically healthy smokers with periodontitis. Each subject was assessed for clinical parameters such as Plaque index, Gingival index, Probing depth, clinical attachment. A polypropylene tube was used to collect unstimulated saliva and centrifuged it at 800 × g for 10 min. Supernatants were collected and stored at -80◦C. A commercially available enzyme-linked immunosorbent assay kit was used to analyse levels of human salivary IL-35.

Results

The average age of the subjects in Group 1, Group 2 and Group 3 were 50.53, 52.93 and 52.07 years respectively. All three groups showed a statistically significant difference in clinical parameters including Plaque index, Gingival index, Probing depth and clinical attachment. The salivary IL-35 level was found to be elevated in non-smokers who have periodontitis compared to smokers with periodontitis and healthy individuals. Despite this, the salivary IL-35 levels were found to be statistically significant among three groups at P < 0.001.

Conclusion

The salivary levels of IL-35 were found to increase in Periodontitis patients with/without smoking, along with increased clinical parameters. IL-35 is considered a influential biomarker for periodontal disease.

Transcriptional regulation of VEGFA expression in T-regulatory cells from breast cancer patients

The initiation of new blood vessel formation (neo-angiogenesis) is one of the primary requirements for the establishment of tumor. As the tumor grows beyond a certain size, a hypoxic-condition arises in the inner core of tumor, triggering the release of chemokines, which attract T-regulatory (Treg) cells in the tumor-site. The presence of FOXP3, a lineage-specific transcription factor, expressing Treg cells in various types of tumor implements immunosuppressive and tumor-promoting strategies. One such strategy is the invitation of endothelial cells for neo-vascularization in the tumor site. Here we report that as the disease progresses, Treg cells from breast cancer patients are capable of secreting high-amount of VEGFA. The VEGFA promoter lacks Treg-specific transcription factor FOXP3 binding site. FOXP3 in association with locus-specific transcription factor STAT3 binds to VEGFA promoter to induce its transcription in Treg cells obtained from breast cancer patients. Treg cell-secreted VEGFA induces neo-angiogenesis from endothelial cells under in-vitro conditions. Targeting Tregs in mice with breast tumor reduces tumor growth as well as the level of neo-angiogenesis in the tumor tissue.

Central Regulatory Role of Cytokines in Periodontitis and Targeting Options

BACKGROUND

Periodontitis is an immune-inflammatory disease that leads to the progressive destruction of bone and connective tissue in the periodontal area. The cytokine network plays a primary role in tissue homeostasis, the recruitment of immune cells to control the pathogenic impact and the regulation of osteoclastic function, thus modulating the intensity and duration of the immune response. This review provides an update on the main cytokines implicated in the pathogenesis and progression of periodontitis and their targeting potential in order to enrich current treatment options.

METHODS

A structured search of bibliographic databases (PubMed, MEDLINE, Scopus) was performed for peer-reviewed cytokine studies focused on periodontitis the last ten years. A qualitative content analysis was performed in screened papers and a critical discussion of main findings is provided.

RESULTS

An altered cytokine profile has been detected in periodontitis patients and the interplay of pro-inflammatory and/or anti-inflammatory cytokines has been associated with disease pathogenesis. Among the most prominent pro-inflammatory cytokines, TNF-α, IL-1β, IL-17, IL-6 and the chemokines CXCL-6, CXCL-8 are overexpressed in periodontitis patients and correlate with disease progression. On the other hand, the anti-inflammatory IL-4 and IL- 11 levels are reduced while IL-12 and IFN-γ expression play a dual role in periodontal disease. Current periodontitis treatment strategies include selective antibiotics, antimicrobial photodynamic therapy and probiotics, which can modulate the cytokine network and when applied in combination with specific anti-cytokine agents can exert additional beneficial effects.

CONCLUSION

It is evident that cytokines play a central regulatory role in the inflammatory process and immune cell response that underlies bone destruction in periodontitis. Specific cytokine targeting should be considered as a complementary therapeutic scheme to current periodontal management.

Interleukin-35 pathobiology in periodontal disease: a systematic scoping review

BACKGROUND

Interleukin (IL)-35 is a novel anti-inflammatory cytokine that is produced by regulatory T cells. IL-35 mediates immunological functions and plays a protective role in several diseases such as asthma and rheumatoid arthritis. However, the role of IL-35 in gingivitis and periodontitis remains unclear. The aim of this study was to systematically review the literature and collecting the available evidence regarding the role of IL-35 in pathogenesis of periodontal disease.

METHODS

A systematic search of electronic databases including MEDLINE, Google Scholar, Cochrane Library, Web of Science, and Scopus was conducted in November 2020 to identify studies addressing the Interleukin-35 pathobiology in periodontal disease. The identified studies were subjected to pre-identified inclusion criteria. The retrived papers were assessed by the authours independently and consensus was reached in cases where disagreement occurred. Articles written in languages other than English, case reports, letters to editors, conference abstracts, theses, and dissertations were excluded from the review.

RESULTS

A total of 176 possibly relevant articles were identified through the search strategy. Finally, 15 papers which met the criteria of eligibility were included in this review by consensus. The included articles were classified based on their design and level of evidence.Three subclinical study, ten cross sectional investigation and two randomized clinical trials constituted the final set of studies in this review. At preclinical level, Il-35 showed inhibitory characteristics regarding alveolar bone resorption of animal periodontitis models. The results of observatory human studies confirmed the presence of high levels of IL-35 in saliva, GCF, serum, and gingival biopsies of patients suffering from inflammatory periodontal disease. Moreover, two included clinical trials showed that non-surgical periodontal therapy could downregulate IL-35 production in chronic periodontitis patients.

CONCLUSION

Interleukin-35 has an undeniable role in pathobiology of inflammatory periodontal disease. Further well-controlled studies are needed to better elucidate the functional pattern of IL-35 in pathogeneisis of gingival and periodontal disease.

Role of Wnt5a in periodontal tissue development, maintenance, and periodontitis: Implications for periodontal regeneration (Review)

The periodontium is a highly dynamic microenvironment constantly adapting to changing external conditions. In the processes of periodontal tissue formation and remodeling, certain molecules may serve an essential role in maintaining periodontal homeostasis. Wnt family member 5a (Wnt5a), as a member of the Wnt family, has been identified to have extensive biological roles in development and disease, predominantly through the non‑canonical Wnt signaling pathway or through interplay with the canonical Wnt signaling pathway. An increasing number of studies has also demonstrated that it serves crucial roles in periodontal tissues. Wnt5a participates in the development of periodontal tissues, maintains a non‑mineralized state of periodontal ligament, and regulates bone homeostasis. In addition, Wnt5a is involved in the pathogenesis of periodontitis. Recently, it has been shown to serve a positive role in the regeneration of integrated periodontal complex. The present review article focuses on recent research studies of Wnt5a and its functions in development, maintenance, and pathological disorders of periodontal tissues, as well as its potential effect on periodontal regeneration.

Cytokines and Their Genetic Polymorphisms Related to Periodontal Disease

Periodontal disease (PD) is a chronic inflammatory disease caused by the accumulation of bacterial plaque biofilm on the teeth and the host immune responses. PD pathogenesis is complex and includes genetic, environmental, and autoimmune factors. Numerous studies have suggested that the connection of genetic and environmental factors induces the disease process leading to a response by both T cells and B cells and the increased synthesis of pro-inflammatory mediators such as cytokines. Many studies have shown that pro-inflammatory cytokines play a significant role in the pathogenesis of PD. The studies have also indicated that single nucleotide polymorphisms (SNPs) in cytokine genes may be associated with risk and severity of PD. In this narrative review, we discuss the role of selected cytokines and their gene polymorphisms in the pathogenesis of periodontal disease.

Evaluation of Salivary Cytokines and Vitamin D Levels in Periodontopathic Patients

Periodontal disease (PD) is an inflammatory condition of the tissues supporting the teeth, which is widespread among the adult population. Evidence shows a relationship between PD and vitamin D levels, which is involved in the regulation of bone metabolism, mineral homeostasis, and inflammatory response. This study aimed to perform a simultaneous evaluation of inflammatory mediators and vitamin D levels in saliva in periodontopathic patients to better understand their role in periodontal disease. In this observational study, clinical periodontal parameter examination was performed for each patient. Moreover, the saliva levels of 25(OH)D₃, TGFβ, IL-35, IL-17A, and MMP9 were evaluated using an ELISA assay. An increase in TGFβ, IL-35, MMP9, and IL-17A salivary levels and a reduction in 25(OH)D₃ levels were observed in periodontopathic patients with respect to the healthy controls. The present study revealed significant positive correlation between cytokines and highly negative correlation between 25(OH)D₃ and salivary cytokine levels. Further studies are needed to better understand if salivary cytokines and vitamin D evaluation may represent a new approach for detection and prevention of progressive diseases, such as PD.

IL-35 and RANKL Synergistically Induce Osteoclastogenesis in RAW264 Mouse Monocytic Cells

Interleukin (IL)-35 is an immunosuppressive cytokine mainly produced by regulatory T cells. IL-35 mediates immunological functions by suppressing the inflammatory immune response. However, the role of IL-35 in bone-destructive diseases remains unclear, especially in terms of osteoclastogenesis. Therefore, the current study investigated the synergistic effect of IL-35 on osteoclastogenesis that is involved the pathogeneses of periodontitis and rheumatoid arthritis. Osteoclastic differentiation and osteoclastogenesis of RAW264 (RAW) cells induced by receptor activator of nuclear factor (NF)-κB ligand (RANKL) and IL-35 were evaluated by tartrate-resistant acid phosphate staining, hydroxyapatite resorption assays, and quantitative polymerase chain reaction. The effect of IL-35 on RANKL-stimulated signaling pathways was assessed by Western blot analysis. Costimulation of RAW cells by RANKL and IL-35 induced osteoclastogenesis significantly compared with stimulation by RANKL alone. Phosphorylations of extracellular signal-regulated kinase (ERK) and p38 mitogen-activated protein kinase tended to be increased by RANKL and IL-35 compared with RANKL or IL-35 alone. Additionally, the osteoclastogenesis induced by RANKL and IL-35 was suppressed by inhibition of ERK. In this study, IL-35 and RANKL induced osteoclastogenesis synergistically. Previous reports have shown that IL-35 suppresses the differentiation of osteoclasts. Therefore, IL-35 might play dual roles of destruction and protection in osteoclastogenesis.