Response In Periodontitis Research Articles

Exploring the interplay between Porphyromonas gingivalis KGP gingipain, herpes virus MicroRNA-6, and Icp4 transcript in periodontitis: Computational and clinical insights.

Porphyromonas gingivalis, a major pathogen in periodontitis, produces KGP (Lys-gingipain), a cysteine protease that enhances bacterial virulence by promoting tissue invasion and immune evasion. Recent studies highlight microRNAs' role in viral latency, potentially affecting lytic replication through host mechanisms. Herpes virus (HSV) establishes latency via interactions between microRNA-6 (miRH-6) and the ICP4 transcription factor in neural ganglia. This suggests a potential link between periodontitis and HSV-induced latency. This study aims to identify and validate the insilico inhibitory interaction of P. gingivalis KGP with ICP4 transcripts and correlate the presence of viral latency-associated transcript micro-RNA-6 with periodontitis. Computational docking analysis was performed to investigate the potential interaction between ICP4 and KGP gingipain. The binding energy and RMSD ligand values were calculated to determine the interaction's strength. Ten patients with recurrent clinical attachment loss despite conventional therapy were included in the clinical study. Subgingival tissue samples were collected post-phase I therapy, and HSV microRNA-6 presence was detected via polymerase chain reaction and confirmed through gel electrophoresis. Computational docking identified the ICP4-KGP gingipain complex with the lowest binding energy (-288.29 kJ mol^1) and an RMSD ligand of 1.5 Angstroms, indicating strong interaction potential. Gel electrophoresis confirmed miRH-6 presence in all samples. The identification of miRNA-6 in periodontitis patients and the strong interaction potential between P. gingivalis KGP gingipain and ICP4 transcripts indicate a possible link between bacterial virulence factors and viral latency dynamics in periodontal tissues. These results highlight the complex interplay between oral pathogens, viral microRNAs, and host immune responses in periodontitis.

Spatial Transcriptomics Unravel the Tissue Complexity of Oral Pathogenesis.

Spatial transcriptomics (ST) is a cutting-edge methodology that enables the simultaneous profiling of global gene expression and spatial information within histological tissue sections. Traditional transcriptomic methods lack the spatial resolution required to sufficiently examine the complex interrelationships between cellular regions in diseased and healthy tissue states. We review the general workflows for ST, from specimen processing to ST data analysis and interpretations of the ST dataset using visualizations and cell deconvolution approaches. We show how recent studies used ST to explore the development or pathogenesis of specific craniofacial regions, including the cranium, palate, salivary glands, tongue, floor of mouth, oropharynx, and periodontium. Analyses of cranial suture patency and palatal fusion during development using ST identified spatial patterns of bone morphogenetic protein in sutures and osteogenic differentiation pathways in the palate, in addition to the discovery of several genes expressed at critical locations during craniofacial development. ST of salivary glands from patients with Sjögren's disease revealed co-localization of autoimmune antigens with ductal cells and a subpopulation of acinar cells that was specifically depleted by the dysregulated autoimmune response. ST of head and neck lesions, such as premalignant leukoplakia progressing to established oral squamous cell carcinomas, oral cancers with perineural invasions, and oropharyngeal lesions associated with HPV infection spatially profiled the complex tumor microenvironment, showing functionally important gene signatures of tumor cell differentiation, invasion, and nontumor cell dysregulation within patient biopsies. ST also enabled the localization of periodontal disease-associated gene expression signatures within gingival tissues, including genes involved in inflammation, and the discovery of a fibroblast subtype mediating the transition between innate and adaptive immune responses in periodontitis. The increased use of ST, especially in conjunction with single-cell analyses, promises to improve our understandings of craniofacial development and pathogenesis at unprecedented tissue-level resolution in both space and time.

Hypoxia-inducible Factor 1α Contributes to Matrix Metalloproteinases 2/9 and Inflammatory Responses in Periodontitis.

Periodontitis is a prevalent condition characterized by inflammation and tissue destruction within the periodontium, with hypoxia emerging as a contributing factor to its pathogenesis. Hypoxia-inducible factor 1α (HIF-1α) has a crucial role in orchestrating adaptive responses to hypoxic microenvironments and has been implicated in various inflammatory-related diseases. Understanding the interplay between HIF-1α, matrix metalloproteinases (MMPs), and inflammatory responses in periodontitis could provide insights into its molecular mechanisms. We investigated the relationship between HIF-1α, MMP2, and MMP9 in gingival crevicular fluid (GCF) and periodontal ligament stem cells (PDLSCs) from periodontitis patients. The expression levels of HIF-1α, MMP2, MMP9, and inflammatory factors (IL-6, IL-1β, TNF-α) were assessed using enzyme-linked immunosorbent assay (ELISA) and real-time PCR (RT-PCR). Additionally, osteogenic differentiation of PDLSCs was identified by alkaline phosphatase activity. Significantly elevated levels of HIF-1α, MMP2, and MMP9 were observed in GCF of periodontitis patients compared to controls. Positive correlations were found between HIF-1α and MMP2/MMP9, as well as with IL-6, IL-1β, and TNF-α. Modulation of HIF-1α expression in PDLSCs revealed its involvement in MMP2/9 secretion and inflammatory responses, with inhibition of HIF-1α mitigating these effects. Furthermore, HIF-1α inhibition alleviated the reduction in osteogenic differentiation induced by inflammatory stimuli. Our findings elucidate the regulatory role of HIF-1α in MMP expression, inflammatory responses, and osteogenic differentiation in periodontitis. In conclusion, targeting HIF-1α signaling pathways may offer therapeutic opportunities for managing periodontitis and promoting periodontal tissue regeneration.

THE IMMUNOMODULATORY ROLE OF CYTOKINES IN THE PATHOGENESIS OF PERIODONTAL DISEASE

Background:Inflammatory periodontal diseases are one of the most acute problems of modern dentistry, which is associated with their widespread prevalence in the world. In the structure of periodontal diseases, periodontitis a leading place in the age group of 40-50 years. Many factors play a role in the etiology of periodontitis, the most important of which are the local microbiota and the host immune response. Cytokines play an extremely important role. Cytokines are key modulators of both homeostasis and inflammatory processes, acting in the first wave of responses against pathogens, stimuli at barrier sites and linking tissue cells to lymphocytes and additional cell populations. Objective:The aim of the study was to analyze modern literature on the role of cytokines in the etiology and pathogenesis of inflammatory periodontal diseases. Materials and methods:Data Extraction: A comprehensive electronic literature search was performed in the following databases:PubMed, Scopus,Web of Scienc, Google Scholar, EBSCO host from 2000 to 2024 terms: periodontitis, infection, inflammation, immunity, cytokines, interleukin. 124 articles were found and 50 full-text articles of high methodological quality were selected according to the review method used, the PRISMA. Inclusion criteria:included clinical trials, considered randomized controlled trials, cross-sectional studies, casecontrol studies, and cohort studies in human subjects that evaluated the current literature on the periodontitis, infection, inflammation, immunity, cytokines, interleukin written in English articles.There was no limitation on minimal quality, minimal sample size, or the number of patients. Exclusion criteria were:original primary studies, due to language limitations , abstracts, letters to the editor, book chapters, case reports, conference abstracts, duplicate publications, and in vitro and in vivo animal experimental studies. Result:Many factors of general and local origin are involved in the development and progression of inflammatory periodontal diseases. Microorganisms and their products cause activation of the host immune system, which results in the release of cytokines and other proinflammatory biomarkers that cause tissue damage. The inflammatory process in periodontal tissues progresses through various stages, beginning with the infiltration of immune cells into the gingival tissue. Immune cells secrete proinflammatory cytokines such as interleukin-1 (IL-1), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α),which further promote inflammation and tissue destruction. The interaction between bacterial biofilm and the immune response, which is mainly controlled by cytokines, determines the course of periodontal disease. Conclusion:The etiology and pathogenesis of periodontal disease is quite complex, diverse and not yet fully disclosed. Cytokines are control and modulate the immune response in periodontitis

Salivary IL-1β, IL-6, and IL-10 Are Key Biomarkers of Periodontitis Severity.

To explore severity and progression biomarkers, we examined the clinical relevance of multiple cytokines and mediators involved in the inflammatory response in periodontitis. A cohort of 68 patients was enrolled in the study and periodontal status assessed by the current classification of periodontal diseases. Immune mediators present in saliva, of both patients and healthy controls, were quantified using a Legendplex-13 panel. Clinic parameters were significantly higher in PD patients compared with HC, with a strong significant association with the disease severity (stage) (p < 0.001), but not with progression (grade). The panel of immune mediators evidenced elevated levels of pro-inflammatory cytokines IL-6 and IL-1β as disease established (p < 0.01). IL-1β/IL-1RA ratio was increased in PD patients, being associated with disease stage. An anti-inflammatory response was spotted by higher IL-10. Lower levels of IL-23 and IP-10 were associated with disease severity. No significant statistical differences were found by grade classification. Moreover, salivary IL-1β and IL-6 exhibited significant positive correlations with several clinical measurements (PI, BOP, PPD, CAL), while IP-10 showed a statistical negative correlation with BOP, PPD, and CAL. These insights highlight the complexity of the periodontitis inflammatory network and the potential of cytokines as biomarkers for refined diagnostic and therapeutic strategies.

Type VI Collagen Deficiency Causes Enhanced Periodontal Tissue Destruction

The periodontal ligament (PDL) is a fibrillar connective tissue that lies between the alveolar bone and the tooth and is composed of highly specialized extracellular matrix (ECM) molecules and a heterogeneous population of cells that are responsible for collagen formation, immune response, bone formation, and chewing force sensation. Type VI collagen (COL6), a widely distributed ECM molecule, plays a critical role in the structural integrity and mechanical properties of various tissues including muscle, tendon, bone, cartilage, and skin. However, its role in the PDL remains largely unknown. Our study shows that deficiency of COL6 impairs PDL fibrillogenesis and exacerbates tissue destruction in ligature-induced periodontitis (LIP). We found that COL6-deficient mice exhibited increased bone loss and degraded PDL in LIP and that fibroblasts expressing high levels of Col6α2 are pivotal in ECM organization and cell-ECM interactions. Moreover, COL6 deficiency in the PDL led to an increased number of fibroblasts geared toward the inflammatory response. We also observed that cultured COL6-deficient fibroblasts from the PDL exhibited decreased expression of genes related to collagen fiber turnover and ECM organization as well as migration and proliferation. Our findings suggest that COL6 plays a crucial role in the PDL, influencing fibroblast function in fibrillogenesis and affecting the immune response in periodontitis. These insights advance our understanding of the molecular mechanisms underlying PDL maturation and periodontal disease.

Retraction Note: Screening of feature genes related to immune and inflammatory responses in periodontitis

Retraction Note: Screening of feature genes related to immune and inflammatory responses in periodontitis

Regulatory role of PDK1 via integrated gene analysis of mitochondria-immune response in periodontitis

AimsTo investigate the association between mitochondrial events and immune response in periodontitis and related regulatory genes. Main methodsGene expression profiles in gingival tissues were retrieved from the Gene Expression Omnibus. Mitochondria-immune response-related differentially expressed genes (MIR-DEGs) between the healthy and periodontitis samples were determined. WGCNA, GO, and KEGG were used to investigate the function and the enriched pathways of MIR-DEGs. The correlation between MIR-DEGs expression and clinical probing pocket depth was analyzed. The MIR-DEGs were further identified and verified in animal samples. A periodontitis model was established in C57BL/6 mice with silk ligation. Micro-computed tomography was used to assess alveolar bone loss. Western blot, quantitative real-time polymerase chain reaction, and immunohistochemical analyses further validated the differential expression of the MIR-DEGs. Key findingsA total of ten MIR-DEGs (CYP24A1, PRDX4, GLDC, PDK1, BCL2A1, CBR3, ARMCX3, BNIP3, IFI27, and UNG) were identified, the expression of which could effectively distinguish patients with periodontitis from the healthy controls. Enhanced immune response was detected in the periodontitis group with that in the healthy controls, especially in B cells. PDK1 was a critical MIR-DEG correlated with B cell immune response and clinical periodontal probing pocket depth. Both animal and clinical periodontal samples presented higher gene and protein expression of PDK1 than the control samples. Additionally, PDK1 colocalized with B cells in both animal and clinical periodontal tissues. SignificanceMitochondria participate in the regulation of the immune response in periodontitis. PDK1 may be the key mitochondria-related gene regulating B-cell immune response in periodontitis.

Periodontitis and lipopolysaccharides: How far have we understood?

Periodontitis is a ubiquitous chronic inflammatory worldwide disease. The multiplicity of gram-negative microbiomes and their endotoxins, such as lipopolysaccharides (LPS), play a crucial role in its pathogenesis. The detection and consequent effects of LPS occur either via membrane-based cluster of differentiation 14 (CD14)/myeloid differentiation factor 2 (MD2)/Toll-like receptor (TLR)-4 complex activation or through intracellular cytosolic LPS detection that further cascades its effects, resulting in a variety of cell death processes, including apoptosis, pyroptosis, necroptosis, NETosis, and their crosstalk. Irrespective of the detection of LPS, the cellular response is for protecting and resolving the inflammation. However, chronic and exaggerated responses in periodontitis result in the destruction of periodontal structures. This review summarizes the extracellular and cytosolic detection of LPS and its further consequences. Then, it sheds light on methods reported to mitigate the adverse effects of LPS.

Salivary levels of azurocidin and soluble azurophilic granules in periodontal disease.

Periodontitis is an infection-driven inflammatory condition of the periodontium. Neutrophils are one of the most important first-line immune cells that protect against pathogen microorganisms in the saliva, but they may also mediate tissue death in inflammatory disorders. The aim of our study was to estimate salivary levels of azurocidin and extracellular azurophilic granules cluster of differentiation (CD63) as biomarkers of neutrophil activation in patients with periodontal diseases and to study the correlation between the levels of these two biomarkers and clinical periodontal parameters. The study included 60 patients with periodontal disease (30 patients with periodontitis and 30 with gingivitis) and 25 healthy controls. The assessed parameters were bleeding on probing, the plaque index, clinical attachment loss, and probing pocket depth. Saliva samples were taken from each study participant, and azurocidin and CD63 levels were measured using ELISA. Azurocidin and CD63 levels were significantly higher in patients with periodontitis and patients with gingivitis than in controls (P < 0.05), and significantly higher in patients with periodontitis than in patients with gingivitis (P < 0.05). Moreover, we found a significant positive correlation between the two biomarkers with clinical attachment loss in the periodontitis group. This study has shown that increased salivary azurocidin and extracellular CD63 levels are associated with enhanced innate response in periodontal disease and can be considered biomarkers of neutrophil activation.

Transferrin receptor 2 mitigates periodontitis-driven alveolar bone loss.

Periodontitis is associated with significant alveolar bone loss. Patients with iron overload suffer more frequently from periodontitis, however, the underlying mechanisms remain largely elusive. Here, we investigated the role of transferrin receptor 2 (Tfr2), one of the main regulators of iron homeostasis, in the pathogenesis of periodontitis and the dental phenotype under basal conditions in mice. As Tfr2 suppresses osteoclastogenesis, we hypothesized that deficiency of Tfr2 may exacerbate periodontitis-induced bone loss. Mice lacking Tfr2 (Tfr2-/- ) and wild-type (Tfr2+/+ ) littermates were challenged with experimental periodontitis. Mandibles and maxillae were collected for microcomputed tomography and histology analyses. Osteoclast cultures from Tfr2+/+ and Tfr2-/- mice were established and analyzed for differentiation efficiency, by performing messenger RNA expression and protein signaling pathways. After 8 days, Tfr2-deficient mice revealed a more severe course of periodontitis paralleled by higher immune cell infiltration and a higher histological inflammation index than Tfr2+/+ mice. Moreover, Tfr2-deficient mice lost more alveolar bone compared to Tfr2+/+ littermates, an effect that was only partially iron-dependent. Histological analysis revealed a higher number of osteoclasts in the alveolar bone of Tfr2-deficient mice. In line, Tfr2-deficient osteoclastic differentiation ex vivo was faster and more efficient as reflected by a higher number of osteoclasts, a higher expression of osteoclast markers, and an increased resorptive activity. Mechanistically, Tfr2-deficient osteoclasts showed a higher p38-MAPK signaling and inhibition of p38-MAPK signaling in Tfr2-deficient cells reverted osteoclast formation to Tfr2+/+ levels. Taken together, our data indicate that Tfr2 modulates the inflammatory response in periodontitis thereby mitigating effects on alveolar bone loss.

Association between periodontitis treatment and dementia in Taiwanese adults

BackgroundThe chronic systemic inflammatory response in periodontitis may be a potential risk factor for dementia, especially in adults. This study determined the association between periodontal treatment and dementia in adults and evaluated the effect of regular scaling treatment on the risk of dementia in this population.MethodsThis case–control study identified 18,930 patients with a dementia-related diagnosis from the Taiwan National Health Insurance Research Database. Scaling and periodontal emergency treatments were evaluated after 1 year and 3 years. Using multivariable logistic regression analysis to evaluate the association between periodontal emergency treatment and dementia risk.ResultsThe results showed that scaling treatment rates were lower in the dementia cohort than the non-dementia cohort after 1 and 3 years. Patients who received periodontal emergency treatment within 3 years had a significantly increased risk of dementia. Furthermore, patients with periodontitis who did not receive scaling treatment within 3 years had a higher risk of dementia than patients without periodontitis (OR, 1.22; 95% CI, 1.10–1.35).ConclusionThis study demonstrated that periodontitis and dementia are associated, and that periodontitis is a risk factor for dementia in adults. The risk of dementia was dependent on the periodontal health status of adults, and our findings suggest that regular scaling can reduce the incidence of dementia in adults. Therefore, regular and routine scaling treatment is suggested for adults.

Proteomic and single-cell analysis shed new light on the anti-inflammatory role of interferonβ in chronic periodontitis.

Periodontitis, a condition that results in periodontal attachment loss and alveolar bone resorption, contributes to the global burden of oral disease. The underlying mechanism of periodontitis involves the dysbiosis and dyshomeostasis between host and oral microbes, among which the macrophage is one of the major innate immune cell players, producing interferon β (IFNβ) in response to bacterial infection. The objective of this research was to examine the interaction of macrophages with periodontitis and the role and mechanism of IFNβ on macrophages. IFNβ has been shown to have the potential to induce the differentiation of M1 to M2 macrophages, which are stimulated by low levels of lipopolysaccharide (LPS). Additionally, IFNβ has been demonstrated to promote the production of ISG15 by macrophages, which leads to the inhibition of the innate immune response. Moreover, our investigation revealed that IFNβ has the potential to augment the secretion of ISG15 and its downstream cytokine, IL10, in LPS-stimulated macrophages. Single-cell analysis was conducted on the gingival tissues of patients with periodontitis, which revealed a higher proportion of macrophages in the periodontitis-diseased tissue and increased expression of IFNβ, ISG15, and IL10. Gene Set Enrichment Analysis indicated that bacterial infection was associated with upregulation of IFNβ, ISG15, and IL10. Notably, only IL10 has been linked to immunosuppression, indicating that the IFNβ-ISG15-IL10 axis might promote an anti-inflammatory response in periodontitis through IL10 expression. It is also found that macrophage phenotype transitions in periodontitis involve the release of higher levels of IFNβ, ISG15, and IL10 by the anti-inflammatory M2 macrophage phenotype compared to the pro-inflammatory M1 phenotype and myeloid-derived suppressor cells (MDSCs). This implies that the IFNβ-induced production of IL10 might be linked to the M2 macrophage phenotype. Furthermore, cell communication analysis demonstrated that IL10 can promote fibroblast proliferation in periodontal tissues via STAT3 signaling.

Effect of bromelain on periodontal destruction and alveolar bone in rats with experimental periodontitis.

Several substances that have anti-inflammatory, antiproteinase, and anti-infective properties have been evaluated as modulators of the inflammatory response in periodontal disease. However, evidence for the anti-inflammatory and antioxidative activities of bromelain is limited. This study evaluated the impact of systemically administered bromelain on the progression of experimental periodontitis. Four equal groups of 32 Wistar albino rats were created as follows (n=8): control, periodontitis+saline, periodontitis+5mg/kg/day bromelain, and periodontitis+10mg/kg/day bromelain. To quantify the resorption of bone and bone volume/tissue volume, bone surface / bone volume, and connectivity, lower jawbones were fixed and then scanned using microcomputed tomography (micro CT). Blood samples were taken to measure the macrophage colony-stimulating factor(M-CSF) concentrations, receptor activator of nuclear factor kappa-Β ligand (RANKL), osteoprotegerin (OPG), tumor necrosis factor-alpha (TNF-α), matrix metalloproteinase-8 (MMP-8), interleukin-6(IL-6), glutathione peroxidase (GPx), superoxide dismutase (SOD), and malondialdehyde (MDA). Histopathological assessments were made to examine the tissue. Treatment with bromelain improved the healing of the periodontium by decreasing the number of leukocytes and ligament deterioration in the gingival connective tissue and by supporting reintegration with alveolar bone. Bromelain used in ligature-induced periodontitis reduced alveolar bone (AB) resorption as measured by microCT; reduced inflammatory parameters such as IL-6 and TNF-α; regulated oxidative-antioxidative processes by increasing GPx and SOD and reducing MDA levels; and regulated AB modeling by decreasing M-CSF, RANKL, and MMP-8 and increasing OPG levels. Bromelain may be an option in periodontal therapy by regulating cytokine levels, improving the healing process, and reducing bone resorption and oxidative stress.

Roles of trained immunity in the pathogenesis of periodontitis.

Periodontitis is a chronic, inflammatory, and destructive disease caused by the imbalance of host immune response and dental biofilm, and has strong epidemiological and pathogenesis correlations with systemic diseases. The immune response in periodontitis involves both innate and adaptive immunity, with numerous immune cells and inflammatory pathways participating in a complex network of interactions. In the past decade, the concept of "trained immunity" has emerged, which highlights the memory characteristics of innate immunity, thus opening up a new avenue of research. There is growing interest in exploring the role of trained immunity in chronic inflammatory and metabolic diseases such as atherosclerosis and diabetes mellitus. Evidence suggests that trained immunity may also regulate the onset and progression of periodontitis, serving as a bridge between periodontitis-related comorbidities. In this review, we summarize concepts related to trained immunity and its development. Furthermore, we present current evidence that endorses the notion of trained immunity in periodontitis and analyze possible roles it may assume regarding periodontitis-associated inflammatory reactions from a cellular perspective. Finally, we discuss various clinical therapeutic strategies for periodontitis and its associated comorbidities that target trained immunity. We hope that more researchers will pay attention to this emerging concept, thereby providing deeper insights into this novel field.

MiR-27a-5p alleviates periodontal inflammation by targeting phosphatase and tensin homolog deleted on chromosome ten.

MicroRNAs (miRNAs), a type of non-coding RNA, have been demonstrated to be essential posttranscriptional modulators in oral diseases and inflammatory responses. However, the specific role of miR-27a-5p in periodontitis requires further investigation. In this study, we used both cellular and animal models to determine how miR-27a-5p affects the pathogenesis of periodontitis and its associated biological functions. Quantitative real-time polymerase chain reaction and western blotting were used to analyze the expression of cytokines, phosphatase and tensin homolog deleted on chromosome ten (PTEN), and miR-27a-5p transcription. Investigation of alveolar bone resorption and inflammation of the periodontium in ligature-induced periodontitis in mice was performed using micro-computed tomography (micro-CT), hematoxylin-eosin (HE) staining, and tartrate-resistant acid phosphatase (TRAP) staining. The binding of miR-27a-5p and PTEN was predicted using the TargetScan database and experimentally confirmed using dual luciferase reporter gene assays. The inflamed gingiva showed lower levels of miR-27a-5p. Macrophages from miR-27a-5p-/- mice produced much higher quantities of pro-inflammatory cytokines owing to the stimulation of Porphyromonas gingivalis lipopolysaccharide, and miR-27a-5p-/- mice with ligature-induced periodontitis also exhibited more severe alveolar bone resorption and damage to the periodontium. Target validation assays identified PTEN as a direct target of bona. Blocking PTEN expression partially reduced inflammation, both in vitro and in vivo. miR-27a-5p alleviated the inflammatory response in periodontitis by targeting PTEN.

OC-STAMP-reactive IgG auto-antibody may upregulate osteoclastogenesis in association with elevated anti-P. gingivalisantibody

Abstract Objectives: Periodontal disease (PD) is a polymicrobial inflammatory lesion in which pathogenic bone loss is caused by osteoclasts (OC) differentiated from MCSF/RANKL-primed monocytes. Elevated IgG antibody to a keystone opportunistic pathogen, Porphyromonas gingivalis (Pg), is a hallmark humoral response in PD that is correlated with pathogenic bone loss. Whereas, a cell membrane protein, osteoclast stimulatory transmembrane protein (OC-STAMP), is engaged in cell-fusion event required for OC-genesis. This study examined the humoral immune responses to OC-STAMP expressed by human monocytes in relation to anti-Pg antibody. Methods: Blood serum (N=10) collected from systemically healthy human subjects (Precision for Medicine) were measured for IgG antibody titer to Pgor OC-STAMP peptides. Human peripheral blood mononuclear cells were stimulated with MCSF/RANKL with or without anti-OC-STAMP rabbit polyclonal antibody or control rabbit IgG. Affinity purified human anti-OC-STAMP antibody was also tested for its activity to alter the OC-genesis. OC-genesis induced in vitrowas evaluated by TRAP staining and pit formation assay. Results: IgG antibody titer to Pgpositively correlated with that to human OC-STAMP peptides (r=0.579, p&amp;lt;0.05). Anti-OC-STAMP auto-antibody purified from human serum with high IgG antibody titer to Pg, as well as anti-OC-STAMP rabbit antibody significantly promoted in vitroOC-genesis (p&amp;lt;0.05). Conclusions: The results indicated that Pginfection may be associated with development of anti-OC-STAMP auto-antibody which can promote OC-genesis, suggesting a novel immunological intervention in the pathogenesis of PD. Supported by grants from NIH NIDCR grants, DE-027851, DE-028715 and DE-331851

Role of mechanosensitive Piezo1 receptor expressed on macrophage in Periodontitis

Abstract Objectives: The mechanosensitive Ca 2+ion channels, Piezo1, converts the mechanical stimulus into cell signals in a variety of immune cells. However, the pathophysiological property of Piezo1 in the oral polymicrobial infectious disease of periodontitis is largely unknown. This study investigated the role of Piezo1 in the inflammatory and phagocytic reactions by RAW264.7 macrophages in response to the exposures to periodontal pathogen, P.gingivalis. Experimental methods: Short hairpin RNA (shRNA) vector for Piezo1 or control scrambled sequence was transfected to RAW264.7 cells. Then, RAW264.7 cells were incubated for 24 hours in the presence or absence of whole P.gingivalis(MOI; 10) or outer membrane vesicles (OMVs, 1 μg/ml) isolated from P.gingivalis, w or w/o Yoda1 (synthetic Piezo1 activator), or shear stress. qPCR was used to monitor the mRNA expressions of Piezo1, TNF-α, TLR-2, and TLR-4, whereas TNF-α protein was detected by ELISA. RAW264.7’s phagocytic ability was evaluated by cytoplasm-internalization of pHrodo-labeled whole P.gingivalisor OMVs using a flow cytometer. Results: OMVs induced more TNF-α production and phagocytosis by RAW264.7 cells than whole P.gingivalis, both of which were further upregulated by Yoda1 as well as shear stress (p&amp;lt;0.05, ANOVA). Shear stress combined with OMV-stimulation upregulated the gene expression of TLR-4, while downregulating TLR-2 gene in RAW264.7 cells. The shRNA-targeting Piezo1 significantly suppressed the TNF-α production and internalization of OMVs by RAW264.7 cells compared control scramble shRNA (p&amp;lt;0.05, ANOVA). Conclusion: The present study indicated that mechanical stress may dysregulate the macrophage-mediated innate immune responses in periodontitis. NIH NIDCR grants, DE-027851, DE-028715 and DE-029709

RETRACTED ARTICLE: Screening of feature genes related to immune and inflammatory responses in periodontitis

BackgroundImmune and inflammatory responses are important in the occurrence and development of periodontitis. The aim of this study was to screen for immune-related genes and construct a disease diagnostic model to further investigate the underlying molecular mechanisms of periodontitis.MethodsGSE16134 and GSE10334 datasets were used in this study. Differentially expressed genes (DEGs) between the periodontitis and control groups were selected. Immune-related genes were identified, and functional analysis and construction of an interaction network were conducted. Immune characteristics were evaluated using gene set variation analysis GSVA. Immunity-related modules were analyzed using weighted gene co-expression network analysis (WGCNA). The LASSO algorithm was applied to optimize the module genes. Correlation between optimized immune-related DEGs and immune cells was analyzed.ResultsA total of 324 immune-related DEGs enriched in immune- and inflammation-related functions and pathways were identified. Of which, 23 immune cells were significantly different between the periodontitis and control groups. Nine optimal immune-related genes were selected using the WGCNA and LASSO algorithms to construct a diagnostic model. Except for CXCL1, the other eight genes were significantly positively correlated with regulatory T cells, immature B cells, activated B cells, and myeloid-derived suppressor cells.ConclusionThis study identified nine immune-related genes and developed a diagnostic model for periodontitis.

Function of Innate Lymphoid Cells in Periodontal Tissue Homeostasis: A Narrative Review

Periodontitis is an irreversible inflammatory response that occurs in periodontal tissues. Given the size and diversity of natural flora in the oral mucosa, host immunity must strike a balance between pathogen identification and a complicated system of tolerance. The innate immune system, which includes innate lymphoid cells (ILCs), certainly plays a crucial role in regulating this homeostasis because pathogens are quickly recognized and responded to. ILCs are a recently discovered category of tissue-resident lymphocytes that lack adaptive antigen receptors. ILCs are found in both lymphoid and non-lymphoid organs and are particularly prevalent at mucosal barrier surfaces, where they control inflammatory response and homeostasis. Recent studies have shown that ILCs are important players in periodontitis; however, the mechanisms that govern the innate immune response in periodontitis still require further investigation. This review focuses on the intricate crosstalk between ILCs and the microenvironment in periodontal tissue homeostasis, with the purpose of regulating or improving immune responses in periodontitis prevention and therapy.