Transitional dendritic cells are distinct from conventional DC2 precursors and mediate proinflammatory antiviral responses.

High-dimensional approaches have revealed heterogeneity amongst dendritic cells (DCs), including a population of transitional DCs (tDCs) in mice and humans. However, the origin and relationship of tDCs to other DC subsets has been unclear. Here we show that tDCs are distinct from other well-characterized DCs and conventional DC precursors (pre-cDCs). We demonstrate that tDCs originate from bone marrow progenitors shared with plasmacytoid DCs (pDCs). In the periphery, tDCs contribute to the pool of ESAM+ type 2 DCs (DC2s), and these DC2s have pDC-related developmental features. Different from pre-cDCs, tDCs have less turnover, capture antigen, respond to stimuli and activate antigen-specific naïve T cells, all characteristics of differentiated DCs. Different from pDCs, viral sensing by tDCs results in IL-1ß secretion and fatal immune pathology in a murine coronavirus model. Our findings suggest that tDCs are a distinct pDC-related subset with a DC2 differentiation potential and unique proinflammatory function during viral infections.

Clonal lineage tracing reveals shared origin of conventional and plasmacytoid dendritic cells.

Developmental origins of dendritic cells (DCs) including conventional DCs (cDCs, comprising cDC1 and cDC2 subsets) and plasmacytoid DCs (pDCs) remain unclear. We studied DC development in unmanipulated adult mice using inducible lineage tracing combined with clonal DNA "barcoding" and single-cell transcriptome and phenotype analysis (CITE-seq). Inducible tracing of Cx3cr1+ hematopoietic progenitors in the bone marrow showed that they simultaneously produce all DC subsets including pDCs, cDC1s, and cDC2s. Clonal tracing of hematopoietic stem cells (HSCs) and of Cx3cr1+ progenitors revealed clone sharing between cDC1s and pDCs, but not between the two cDC subsets or between pDCs and B cells. Accordingly, CITE-seq analyses of differentiating HSCs and Cx3cr1+ progenitors identified progressive stages of pDC development including Cx3cr1+ Ly-6D+ pro-pDCs that were distinct from lymphoid progenitors. These results reveal the shared origin of pDCs and cDCs and suggest a revised scheme of DC development whereby pDCs share clonal relationship with cDC1s.

High-Dimensional Phenotypic Mapping of Human Dendritic Cells Reveals Interindividual Variation and Tissue Specialization.

Given the limited efficacy of clinical approaches that rely on ex vivo generated dendritic cells (DCs), it is imperative to design strategies that harness specialized DC subsets in situ. This requires delineating the expression of surface markers by DC subsets among individuals and tissues. Here, we performed a multiparametric phenotypic characterization and unbiased analysis of human DC subsets in blood, tonsil, spleen, and skin. We uncovered previously unreported phenotypic heterogeneity of human cDC2s among individuals, including variable expression of functional receptors such as CD172a. We found marked differences in DC subsets localized in blood and lymphoid tissues versus skin, and a striking absence of the newly discovered Axl+ DCs in the skin. Finally, we evaluated the capacity of anti-receptor monoclonal antibodies to deliver vaccine components to skin DC subsets. These results offer a promising path for developing DC subset-specific immunotherapies that cannot be provided by transcriptomic analysis alone.

Elevated serum hepatic transaminases in apical periodontitis individuals.

AIM: Apical periodontitis (AP) is the chronic inflammation of the periradicular tissues in response to root canal infection. Whilst AP has been linked with systemic inflammation and noncommunicable diseases, its potential association with nonalcoholic fatty liver disease (NAFLD) is unknown. We aimed to evaluate the serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels as surrogate markers of hepatic injury, and the systemic inflammatory burden in otherwise healthy individuals with and without AP diagnosis. METHODOLOGY: Cross-sectional study. Individuals with AP (n = 30) and healthy controls (n = 29) were recruited. The number, mean diameter (mm) and periapical index of the apical lesions of endodontic origin (ALEO) were assessed. ALT and AST levels (pg/mL) were measured through enzyme-linked immunosorbent assays. The serum levels of TNF-α, IL-4, IL-9, IL-10, IL-17A and IL-22 were evaluated by Multiplex assay. Inferential analysis was performed using t-test or Mann-Whitney tests according to data distribution and linear regression models. Data were analysed with StataV16 (p < .05). RESULTS: ALT and AST levels were significantly higher in individuals with AP compared to controls (p < .05). Serum inflammatory biomarkers showed no significant differences between the study groups. Bivariate and multivariate analyses confirmed that AP diagnosis was independently associated with ALT and AST elevations (p < .05). Additionally, the number of ALEO positively influenced AST levels (p = .002). IL-22 on the other hand, was associated with reduced ALT levels (p = .043). CONCLUSION: AP is associated with higher serum hepatic transaminases ALT and AST, potentially contributing to NAFLD physiopathology in young adults.

TNF-alpha gene promoter's hypomethylation mediates a pro-inflammatory phenotype in peripheral blood monocytes from apical periodontitis individuals.

AIM: Epigenetic regulation of the key inflammatory genes plays a crucial role in controlling monocyte/macrophage-mediated local and systemic responses to bacterial challenges. However, it has not been addressed in apical periodontitis (AP). We aimed to explore the methylation pattern of the TNF-α gene promoter and its association with the inflammatory phenotype of peripheral blood monocytes from individuals with AP and controls. METHODS: A cross-sectional study was conducted, including otherwise healthy individuals with AP (n = 25) and controls (n = 29). Monocytes were isolated from the volunteer's blood samples using a Ficoll gradient followed by negative immunoselection. RNA and DNA were extracted. The DNA methylation profiles of the TNF-α gene promoter region were analyzed using bisulfite sequencing PCR. The mRNA expression levels of DNA methyltransferases 3a (DNMT3a) and Ten Eleven Translocation enzymes 1(TET1) were assessed by qPCR. A fraction of primary monocytes was also cultured for 24 h, and the supernatant was collected to measure cytokine levels through a Luminex assay. Generalized structural equation models (GSEM) evaluated the association between AP, DNA methylation, and TNF-α protein expression controlled for potential covariates. Models included the effect of the methylation of TNF-α gene promoter as a mediator of the association between AP and TNF-α protein expression levels. RESULTS: Monocytes from AP individuals exhibited a heightened secretion of TNF-α and IL-1ß and hypomethylation of the TNF gene promoter (p < .05). AP diagnosis was associated with the TNF-α gene promoter´s hypomethylated profile and enhanced pro-inflammatory cytokine levels, while lower methylation of the gene promoter region and -163 CpG single site mediated TNF-α overexpression (p < .05). CONCLUSIONS: DNA hypomethylation at the TNF-α gene mediates a proinflammatory phenotype in monocytes from AP patients, supporting a role in the systemic response.

Reduced C-reactive protein levels after root canal treatment in clinically healthy young apical periodontitis individuals at cardiovascular risk. A prospective study.

AIM: To determine the systemic inflammatory burden, including hsCRP and its monomeric forms, in patients with apical lesions of endodontic origin treated with root canal treatment (RCT). METHODOLOGY: Prospective pre-/post-study. Apical periodontitis (AP) individuals aged 16-40 were included (N = 29). Individuals received RCT and were followed at 1 and 6 months. Fasting blood samples were obtained. Apical lesions of endodontic origin (ALEO) diameter (mm), and periapical index (PAI), were recorded. The serum concentrations of total hsCRP were determined by turbidimetry. Tumour necrosis factor (TNF)-α, interleukin (IL)-6, IL-10, IL-1ß, and soluble (s) E-selectin were assessed by Multiplex assay. Additionally, mCRP forms were determined in the serum of AP patients with a baseline moderate to high cardiovascular risk based on hsCRP stratification (hsCRP ≥1 mg/L) by immunowestern blot (n = 15). Also, CRP isoforms were explored in ALEOs from AP individuals (n = 4). Data were analysed with StataV16. RESULTS: Periapical index and ALEO sizes were reduced at both follow-up visits after RCT (p < .05). Serum levels of TNF-α, IL-6, IL-10, IL-1ß, and sE-selectin did not show significant differences. CRP was borderline reduced at 1 month (p = .04); however, in AP individuals at cardiovascular risk (hsCRP ≥ 1 mg/L), hsCRP and its monomeric isoform significantly decreased at 1 and 6 months (p < .05). CONCLUSIONS: High-sensitivity CRP and mCRP are reduced after RCT in AP individuals at cardiovascular risk.

Hematology of Liolaemus pacha (Iguania: Liolaemidae) and its relationship with mite infestation, reproductive period and body condition.

Variations in hematological profile in reptiles can be caused by multiple factors, including parasites presence. Our goals were to identify and morphologically describe blood cells of Liolaemus pacha and analyze their relationship with sex, body condition, individual reproductive/post-reproductive period and mite infestation. Blood smear analyses do not indicate the presence of hemoparasites, suggesting that the mites Neopterygosoma do not serve as vectors for these organisms, as has been proposed for other genera of ectoparasitic mites. In post-reproductive period, there was a reduction in specimens' body condition and a higher leukocyte count in uninfected lizards. This could be a consequence of the testosterone effects, in higher concentration during the reproductive season, which can increase the metabolic rate, decreasing feeding rate. Infested and non-infested lizards showed no differences in body condition, as well as in leukocyte count, hence the host's immune system could be developing infestation tolerance. Infested specimens had a higher count of monocytes, thrombocytes, heterophils and lymphocytes. Based on cells function, mites' effect could be associated with inflammatory processes, allergic reactions or infectious diseases. These results suggested a complex interaction between lizards' hematological parameters and factors associated to ectoparasites or body conditions. We consider this work as a diagnostic tool for genus Liolaemus, to evaluate health quality, with relevance to the conservation or management of this lizard's genus.

Machine learning and deep learning models for the diagnosis of apical periodontitis: a scoping review.

OBJECTIVES: To assess the existing literature on the use of machine learning (ML) and deep learning (DL) models for diagnosing apical periodontitis (AP) in humans. MATERIALS AND METHODS: A scoping review was conducted following the Arksey and O'Malley framework. The PubMed, SCOPUS, and Web of Science databases were searched, focusing on articles using ML/DL approaches for AP diagnosis. No restrictions were applied. Two independent reviewers screened publications and charted data in predefined Excel tables for analysis. RESULTS: Nineteen publications focused on diagnosing AP by identifying periapical radiolucent lesions (PRLs) in dental radiographs were included. The average sensitivity and specificity for reviewed models were 83% and 90%, respectively. Only three studies explored the direct impact of artificial intelligence (AI) assistance on clinicians' diagnostic performance. Both consistently showed improved sensitivity without compromising specificity. Significant variability in dataset sizes, labeling techniques, and algorithm configurations was noticed. CONCLUSIONS: Findings affirm AI models' effectiveness and transformative potential in diagnosing AP by improving the accurate detection of periapical radiolucencies using dental radiographs. However, the lack of standardized reporting on crucial aspects of methodology and performance metrics prevents establishing a definitive diagnostic approach using AI. Further studies are needed to expand AI applications in AP diagnosis beyond radiographic analysis. CLINICAL RELEVANCE: AI can potentially improve diagnostic accuracy in AP diagnosis by enhancing the sensitivity of PRL detection in dental radiographs without compromising specificity.

A Molecular Characterization of the Allelic Expression of the BRCA1 Founder Δ9-12 Pathogenic Variant and Its Potential Clinical Relevance in Hereditary Cancer.

Hereditary breast and ovarian cancer (HBOC) syndrome is a genetic condition that increases the risk of breast cancer by 80% and that of ovarian cancer by 40%. The most common pathogenic variants (PVs) causing HBOC occur in the BRCA1 gene, with more than 3850 reported mutations in the gene sequence. The prevalence of specific PVs in BRCA1 has increased across populations due to the effect of founder mutations. Therefore, when a founder mutation is identified, it becomes key to improving cancer risk characterization and effective screening protocols. The only founder mutation described in the Mexican population is the deletion of exons 9 to 12 of BRCA1 (BRCA1Δ9-12), and its description focuses on the gene sequence, but no transcription profiles have been generated for individuals who carry this gene. In this study, we describe the transcription profiles of cancer patients and healthy individuals who were heterozygous for PV BRCA1Δ9-12 by analyzing the differential expression of both alleles compared with the homozygous BRCA1 control group using RT-qPCR, and we describe the isoforms produced by the BRCA1 wild-type and BRCA1Δ9-12 alleles using nanopore long-sequencing. Using the Kruskal-Wallis test, our results showed a similar transcript expression of the wild-type allele between the healthy heterozygous group and the homozygous BRCA1 control group. An association between the recurrence and increased expression of both alleles in HBOC patients was also observed. An analysis of the sequences indicated four wild-type isoforms with diagnostic potential for discerning individuals who carry the PV BRCA1Δ9-12 and identifying which of them has developed cancer.

Lipopolysaccharides from Porphyromonas endodontalis and Porphyromonas gingivalis promote angiogenesis via Toll-like-receptors 2 and 4 pathways in vitro.

AIM: Angiogenesis contributes to the development of apical periodontitis, periodontitis, and other oral pathologies; however, it remains unclear how this process is triggered. The aim was to evaluate whether lipopolysaccharide (LPS) from Porphyromonas endodontalis and Porphyromonas gingivalis induced angiogenesis-related effects in vitro via TLR2 and TLR4. METHODOLOGY: Porphyromonas endodontalis LPS (ATCC 35406 and clinical isolate) was purified with TRIzol, whereas P. gingivalis LPS was obtained commercially. The effects of the different LPS (24 h) in endothelial cell migration were analysed by Transwell assays, following quantification in an optical microscope (40×). The effects of LPS on FAK Y397 phosphorylation were assessed by Western blotting. Angiogenesis in vitro was determined in an endothelial tube formation assay (14 h) in Matrigel in the absence or presence of either LPS. IL-6 and VEGF-A levels were determined in cell supernatants, following 24 h treatment with LPS, and measured in multiplex bead immunoassay. The involvement of TLR2 and TLR4 was assessed with blocking antibodies. The statistical analysis was performed using STATA 12® (StataCorp LP). RESULTS: The results revealed that P. endodontalis LPS, but not P. gingivalis LPS, stimulated endothelial cell migration. Pre-treatment with anti-TLR2 and anti-TLR4 antibodies prevented P. endodontalis LPS-induced cell migration. P. endodontalis LPS promoted FAK phosphorylation on Y397, as observed by an increased p-FAK/FAK ratio. Both P. gingivalis and P. endodontalis LPS (ATCC 35406) induced endothelial tube formation in a TLR-2 and -4-dependent manner, as shown by using blocking antibodies, however, only TLR2 blocking decreased tube formation induced by P. endodontalis (clinical isolate). Moreover, all LPS induced IL-6 and VEGF-A synthesis in endothelial cells. TLR2 and TLR4 were required for IL-6 induction by P. endodontalis LPS (ATCC 35406), while only TLR4 was involved in IL-6 secretion by the other LPS. Finally, VEGF-A synthesis did not require TLR signalling. CONCLUSION: Porphyromonas endodontalis and P. gingivalis LPS induced angiogenesis via TLR2 and TLR4. Collectively, these data contribute to understanding the role of LPS from Porphyromonas spp. in angiogenesis and TLR involvement.

Obesity is related to maternal periodontitis severity in pregnancy: a cross-sectional study.

OBJECTIVES: To evaluate the relationship between obesity and periodontitis staging compared with periodontal healthy or gingivitis in pregnant women. MATERIALS AND METHODS: An analytical cross-sectional study was conducted on pregnant women between 11 and 14 weeks of pregnancy. Sociodemographic, clinical, obstetric, and periodontal variables were studied. The exposure variable was obesity (body mass index [BMI] ≥ 30), and the primary outcome was periodontitis staging versus periodontal healthy/gingivitis. Data were analysed and estimated by multinomial logistic regression models. RESULTS: The present study screened 1086 pregnancies and analysed 972 women with a median age of 29 years; 36.8% were diagnosed as obese. 26.9% of patients were diagnosed as periodontal healthy or gingivitis, 5.5% with stage I periodontitis, 38.6% with stage II periodontitis, 24% with stage III periodontitis, and 5.1% with stage IV periodontitis. After identifying and adjusting for confounding variables (educational level and plaque index), obesity had a relative risk ratio (RRR) of 1.66 (95% CI: 1.05-2.64; p = 0.03) and 1.57 (95% CI: 1.09-2.27; p = 0.015) for stage III periodontitis compared to periodontal healthy/gingivitis and stage II periodontitis, respectively. CONCLUSION: Besides the already known risk indicators for periodontitis (age, smoking, and educational level), our study suggests a relationship between obesity and periodontitis staging in pregnancy. CLINICAL RELEVANCE: Obesity can alter host immune responses, leading to increased susceptibility to infections and overactive host immunity, which could influence the prevalence and severity of maternal periodontitis in pregnancy.

Association of Periodontitis and Atopic Dermatitis with the Levels of IL-13, IL-31, and TSLP in the Gingival Crevicular Fluid.

Emerging epidemiological evidence links atopic dermatitis (AD) and periodontitis, although the mechanisms remain unclear. Th2-derived cytokines are key in the development of both diseases, and different gingival crevicular fluid (GCF) profiles among healthy and diseased subjects have been previously reported. This case-control study examined the GCF levels of interleukins (IL)-13, IL-31, and thymic stromal lymphopoietin (TSLP) in 29 subjects with moderate-to-severe AD and 33 controls. All subjects underwent comprehensive clinical and oral evaluations, followed by GCF collection. GCF levels of IL-13, IL-31, and TSLP were assessed using a multiplex-bead immunoassay. Demographic and periodontal parameters were similar among groups (p > 0.05). The GCF levels of IL-31 and TSLP were higher in AD subjects compared to controls (p < 0.05), whereas no significant differences in the GCF levels of IL-13 were noticed (p = 0.377). Moderate-to-severe AD was positively associated with the GCF levels of IL-31 and TSLP, whereas severe periodontitis was negatively associated with IL-31 (p < 0.05). The GCF levels of IL-13 showed no significant associations with either condition (p = 0.689). There was no significant interaction between AD and periodontitis for IL-31 (p < 0.869). These results suggest that AD and periodontitis independently influence the GCF levels of IL-31 in opposing ways, whereas AD alone influences the levels of TSLP.

A Pathogenic Variant Reclassified to the Pseudogene PMS2P1 in a Patient with Suspected Hereditary Cancer.

The PMS2 gene is involved in DNA repair by the mismatch repair pathway. Deficiencies in this mechanism have been associated with Lynch Syndrome (LS), which is characterized by a high risk for colorectal, endometrial, ovarian, breast, and other cancers. Germinal pathogenic variants of PMS2 are associated with up to 5% of all cases of LS. The prevalence is overestimated for the existence of multiple homologous pseudogenes. We report the case of a 44-year-old woman diagnosed with breast cancer at 34 years without a relevant cancer family history. The presence of pathogenic variant NM_000535.7:c.1A > T, (p.Met1Leu) in PMS2 was determined by next-generation sequencing analysis with a panel of 322 cancer-associated genes and confirmed by capillary sequencing in the patient. The variant was determined in six family members (brothers, sisters, and a son) and seven non-cancerous unrelated individuals. Analysis of the amplified region showed high homology of PMS2 with five of its pseudogenes. We determined that the variant is associated with the PMS2P1 pseudogene following sequence alignment analysis. We propose considering the variant c.1A > T, (p.Met1Leu) in PMS2 for reclassification as not hereditary cancer-related, given the impact on the diagnosis and treatment of cancer patients and families carrying this variant.

lncRNAs in mesenchymal differentiation.

In recent years, technological advances have revealed a large potential number of long noncoding RNAs (lncRNAs). Findings recognize lncRNAs as orchestrating molecules in a wide range of processes, at the transcriptional and posttranscriptional levels, although fewer studies address function. For differentiation, which consists of rearrangements in the gene expression profile and activation of stage- and cell type-dependent signaling mechanisms, the relevance of lncRNAs becomes crucial. The relationship between lncRNAs and key molecular factors in differentiation is strengthening; therefore the present review aims to comprehensively explain the role of lncRNAs in the signaling network involved in the main types of mesenchymal differentiation: adipogenesis, chondrogenesis, myogenesis, and osteogenesis. Notably, a step toward the integration of lncRNAs in the field of cell differentiation promises an exceptional impact.

Leveraging WHO's Global Benchmarking Tool to strengthen capacity in clinical trials oversight for public health emergencies: the GHPP VaccTrain model.

BACKGROUND: A stable, well-functioning and integrated national medicines regulatory system is a core component of health systems resilient against infectious disease outbreaks. In many low- and middle-income countries, however, sizable gaps exist in the emergency preparedness framework of national regulatory authorities (NRAs). RegTrain-VaccTrain is a project of Germany Ministry of Health's Global Health Protection Programme that contributes to global efforts aimed at strengthening such regulatory systems by providing technical support and advice to partner NRAs. In this study, we probed the outputs of our capacity-strengthening activities for clinical trials oversight (CTO) to take stock of progress made and examine remaining priorities in order to provide specialized technical assistance in addressing them to improve operational readiness for emergencies. METHOD: Data validated from NRA self-benchmarking results in 2017 and worksheet records of November 2021 were utilized to assess the emergency preparedness capacity for CTO in three VaccTrain partner NRAs (Liberia, Sierra Leone, The Gambia) before and after interventional capacity-strengthening partnership, using specific public health emergency-related (sub-)indicators of the WHO Global Benchmarking Tool. RESULTS: A generally weak and vulnerable structural framework for CTO characterized the emergency preparedness capacity in all three partner NRAs at baseline, thus putting their operational readiness for public health emergencies at risk. VaccTrain's collaborative work was successful at supporting individual NRAs to develop the full spectrum of operational structures (including (draft) regulations, guidelines, and standard operating procedures) required to improve regulatory preparedness. A gap in the formal approval and implementation of developed legal documents in two of three NRAs still remains. Notwithstanding, a robust emergency framework now exists and the NRAs stand better prepared to respond to (future) locally-concerning health emergencies, during which time clinical trials activity was observed to heighten. CONCLUSIONS: These results exemplify a north-south capacity-strengthening partnership model that effectively contributes in developing structures to enhance regulatory oversight and support expeditious product development in response to crises. They further underscore the equally critical role local/national processes play in facilitating the full implementation of developed structures.

Polarization Profiles of T Lymphocytes and Macrophages Responses in Periodontitis.

Periodontitis is a multifactorial, chronic inflammatory disease affecting the supporting structures of teeth triggered by the complex interactions between a dysbiotic bacterial biofilm and the host's immune response that results in the characteristic loss of periodontal attachment and alveolar bone. The differential phenotypic presentations of periodontitis emerge from inter-individual differences in immune response regulatory mechanisms. The monocyte-macrophage system has a crucial role in innate immunity and the initiation of the T and B lymphocyte adaptive immune responses. Macrophages involve a heterogeneous cell population that shows wide plasticity and differentiation dynamics. In response to the inflammatory milieu, they can skew at the time of TLR ligation to predominant M1 -pro-inflammatory- or M2 -anti-inflammatory/healing- functional phenotypes. The perpetuation of inflammation by M1 macrophages leads to the recruitment of the adaptive immune response, promoting Th1, Th17, and Th22 differentiation, which are directly associated with periodontal breakdown. In contrast, M2 macrophages induce Th2 and Treg responses which are associated with periodontal homeostasis. In this article, we review the recent advances comprising the role of macrophages and lymphocyte polarization profiles and their reprogramming as potential therapeutic strategies. For this purpose, we reviewed the available literature targeting periodontitis, macrophage, and lymphocyte subpopulations with an emphasis in the later 5 years. The active reprogramming of macrophages and lymphocytes polarization crosstalk opens a promising area for therapeutic development.

Role of TLR9 methylation on its active transcription in apical inflammation.

AIM: To explore the methylation pattern, its role in transcriptional regulation and potential modifiers of methylation of the TLR9 gene in chronic periapical inflammation. METHODOLOGY: In this cross-sectional study, apical lesions of endodontic origin (ALEO, n = 61) and healthy periodontal ligaments (HPL, n = 15) were included. Products from bisulfited and PCR-amplified DNA were analysed for their methylation profiles in the promoter region and at each CpG island. Additionally, TLR9 mRNA levels were quantified by qPCR and bivariate and multiple modelling were performed to better understand the influence of methylation on gene transcription. RESULTS: TLR9 mRNA levels were upregulated in ALEO compared to HPL (p < .001). TLR9 promoter CpG sites and CpG +2086 in the intragenic island 1 were demethylated in ALEO compared to HPL (p < .05). Multivariate analysis, adjusted by smoking and gender, revealed that demethylation of TLR9 promoter sites enhanced transcriptional activity, specifically demethylated CpGs at positions -736 and -683, (p = .02), which are close to CRE binding. Although ALEO reduced the global methylation of the gene promoter and intragenic-island 2 (p < .05) by -42.5 and -9.5 percentage points, respectively, age reduced the global methylation of intragenic-island 3 within the exon 2. CONCLUSIONS: Demethylations of TLR9 promoter CpG sites, along with the intragenic DNA methylation status, were involved in higher transcription in ALEO. Hence, chronic periapical inflammation and ageing modify the methylation status both in the gene promoter and in intragenic CpG islands.

Systemic burden and cardiovascular risk to Porphyromonas species in apical periodontitis.

OBJECTIVE: Porphyromonas (P.) species (spp.) are a major etiological agent of apical periodontitis (AP), which in turn represents a risk factor for cardiovascular diseases. This study explored the associations between endodontic infection with Porphyromonas species, the systemic bacterial burden, and cardiovascular risk, based on high-sensitivity C-reactive protein (hsCRP), in young adults with AP. MATERIALS AND METHODS: Cross-sectional study. Otherwise, healthy individuals with AP and controls (n = 80, ≤ 40 years) were recruited at the University Dental Clinic. Oral parameters and classic cardiovascular risk factors were registered. Endodontic Porphyromonas endodontalis and Porphyromonas gingivalis were identified using conventional PCR. Serum concentrations of anti-P. endodontalis and anti-P. gingivalis antibodies, and endotoxins were determined through ELISA and Limulus-amebocyte assays. Serum hsCRP was determined for cardiovascular risk stratification. RESULTS: Intracanal detection of P. endodontalis and P. gingivalis in AP were 33.3% and 22.9%, respectively. Serum anti-P. endodontalis and anti-P. gingivalis IgG was higher in AP than controls (p < 0.05 and p = 0.057, respectively). Intracanal P. endodontalis associated with higher endotoxemia (p < 0.05). Among endodontic factors, the presence (OR 4.2-5.5, p < 0.05) and the number of apical lesions (OR 2.3, p < 0.05) associated with moderate-severe cardiovascular risk, whereas anti-P. endodontalis IgG were protective (OR 0.3, p > 0.05). CONCLUSIONS: AP and infection with P. endodontalis positively associated with cardiovascular risk based on hsCRP levels and endotoxemia, respectively, whereas anti-P. endodontalis IgG response seems to be protective against low-grade systemic inflammation. CLINICAL RELEVANCE: Apical periodontitis and endodontic P. endodontalis can influence the systemic burden with impact on the surrogate cardiovascular risk marker hsCRP, providing mechanistic links.

Lipopolysaccharide from Porphyromonas gingivalis, but Not from Porphyromonas endodontalis, Induces Macrophage M1 Profile.

Apical Lesions of Endodontic Origin (ALEO) are initiated by polymicrobial endodontic canal infection. Porphyromonas gingivalis (Pg) and Porphyromonas endodontalis (Pe) lipopolysaccharides (LPS) can induce a pro-inflammatory macrophage response through their recognition by TLR2 and TLR4. However, polarization responses induced by Pg and/or Pe LPS in macrophages are not fully understood. We aimed to characterize the polarization profiles of macrophages differentiated from THP-1 cells following Pg and/or Pe LPS stimulation from reference strain and clinical isolates. A modified LPS purification protocol was implemented and the electrophoretic LPS profiles were characterized. THP-1 human monocytes differentiated to macrophages were stimulated with Pg and Pe LPS. Polarization profiles were characterized through cell surface markers and secreted cytokines levels after 24 h of stimulation. TLR2 and TLR4 cell surfaces and transcriptional levels were determined after 24 or 2 h of LPS stimulation, respectively. LPS from Pg induced a predominant M1 profile in macrophages evidenced by changes in the expression of the surface marker CD64 and pro-inflammatory cytokine profiles, TNF-α, IL-1ß, IL-6, and IL-12. Pe LPS was unable to induce a significant response. TLR2 and TLR4 expressions were neither modified by Pg or Pe LPS. Pg LPS, but not Pe LPS, induced a macrophage M1 Profile.

Exploring the Expression of Pro-Inflammatory and Hypoxia-Related MicroRNA-20a, MicroRNA-30e, and MicroRNA-93 in Periodontitis and Gingival Mesenchymal Stem Cells under Hypoxia.

Hypoxia associated with inflammation are common hallmarks observed in several diseases, and it plays a major role in the expression of non-coding RNAs, including microRNAs (miRNAs). In addition, the miRNA target genes for hypoxia-inducible factor-1α (HIF-1α) and nuclear factor of activated T cells-5 (NFAT5) modulate the adaptation to hypoxia. The objective of the present study was to explore hypoxia-related miRNA target genes for HIF-1α and NFAT5, as well as miRNA-20a, miRNA-30e, and miRNA-93 expression in periodontitis versus healthy gingival tissues and gingival mesenchymal stem cells (GMSCs) cultured under hypoxic conditions. Thus, a case-control study was conducted, including healthy and periodontitis subjects. Clinical data and gingival tissue biopsies were collected to analyze the expression of miRNA-20a, miRNA-30e, miRNA-93, HIF-1α, and NFAT5 by qRT-PCR. Subsequently, GMSCs were isolated and cultured under hypoxic conditions (1% O2) to explore the expression of the HIF-1α, NFAT5, and miRNAs. The results showed a significant upregulation of miRNA-20a (p = 0.028), miRNA-30e (p = 0.035), and miRNA-93 (p = 0.026) in periodontitis tissues compared to healthy gingival biopsies. NFAT5 mRNA was downregulated in periodontitis tissues (p = 0.037), but HIF-1α was not affected (p = 0.60). Interestingly, hypoxic GMSCs upregulated the expression of miRNA-20a and HIF-1α, but they downregulated miRNA-93e. In addition, NFAT5 mRNA expression was not affected in hypoxic GMSCs. In conclusion, in periodontitis patients, the expression of miRNA-20a, miRNA-30e, and miRNA-93 increased, but a decreased expression of NFAT5 mRNA was detected. In addition, GMSCs under hypoxic conditions upregulate the HIF-1α and increase miRNA-20a (p = 0.049) expression. This study explores the role of inflammatory and hypoxia-related miRNAs and their target genes in periodontitis and GMSCs. It is crucial to determine the potential therapeutic target of these miRNAs and hypoxia during the periodontal immune-inflammatory response, which should be analyzed in greater depth in future studies.