α-IRAK-4 Suppresses the Activation of RANK/RANKL Pathway on Macrophages Exposed to Endodontic Microorganisms.

Periapical lesions are common pathologies affecting the alveolar bone, often initiated by intraradicular lesions resulting from microbial exposure to dental pulp. These microorganisms trigger inflammatory and immune responses. When endodontic treatment fails to eliminate the infection, periapical lesions persist, leading to bone loss. The RANK/RANKL/OPG pathway plays a crucial role in both the formation and the destruction of the bone. In this study, the objective was to inhibit the RANK/RANKL pathway in vitro within exposed Thp-1 macrophages to endodontic microorganisms, specifically Enterococcus faecalis, which was isolated from root canals of 20 patients with endodontic secondary/persistent infection, symptomatic and asymptomatic, and utilizing an α-IRAK-4 inhibitor, we introduced endodontic microorganisms and/or lipoteichoic acid from Streptococcus spp. to cellular cultures in a culture plate, containing thp-1 cells and/or PBMC from patients with apical periodontitis. Subsequently, we assessed the percentages of RANK+, RANKL+, and OPG+ cells through flow cytometry and measured the levels of several inflammatory cytokines (IL-1ß, TNF-α, IL-6, IL-8, IL-10, and IL-12p70) in the cellular culture supernatant through a CBA kit and performed analysis by flow cytometry. A significant difference was observed in the percentages of RANK+RANKL+, OPG+ RANKL+ cells in thp-1 cells and PBMCs from patients with apical periodontitis. The findings revealed significant differences in the percentages of the evaluated cells, highlighting the novel role of the IRAK-4 inhibitor in addressing this oral pathology, apical periodontitis, where bone destruction is observed.

Analysis of T follicular and T peripheral helper lymphocytes in autoimmune thyroid disease.

PURPOSE: Peripheral helper T (Tph) cells have an important role in the induction of humoral immune responses and autoantibody production. Accordingly, it is feasible that this lymphocyte subset has a relevant role in the pathogenesis of autoimmune thyroid diseases (AITD). In this study we aim to analyze the levels and function of Tph cells in blood samples from patients with AITD. METHODS: We performed an observational study with cases and controls. Blood samples were obtained from nineteen patients with Hashimoto's thyroiditis (HT), twenty-four with Graves' disease (GD), and fifteen healthy controls. In addition, the levels of follicular T helper (Tfh) cells and Tph cells, the release of interleukin-21 (IL-21) by these lymphocytes and the number of plasmablasts were analyzed by multi-parametric flow cytometry analyses. RESULTS: Increased percentages of Tfh and Tph lymphocytes were detected in patients with HT and GD. Furthermore, an enhanced synthesis of the cytokine IL-21 by these cells was observed. Accordingly, we detected significant higher percentages of plasmablasts in patients with GD, and these values tended to be also higher in HT patients. Moreover, significant positive associations were observed between the levels of Tfh or Tph and the number of plasmablast or anti-TSHR Ab titers in patients with AITD. CONCLUSION: Our data suggest that Tph lymphocytes may have a relevant role in the pathogenesis of AITD.

Increased IL-12p70 and IL-8 Produced by Monocytes in Response to Streptococcus spp. and Actinomyces spp. Causals of Endodontic Primary Infections.

We sought to evaluate the effect of endodontic-causative microorganisms of primary infections on mononuclear cells such as CD14+, CD4+, CD8+, CD19+ and Tregs Foxp3+. Facultative anaerobic microorganisms were isolated from radicular conducts and peripheral blood samples, which were taken from patients with primary infections. Cellular cultures were performed with peripheral blood mononuclear cells (PBMC) with and without Actinomyces spp. and Streptococcus spp. during 48, 72, and 96 h of contact in culture (concentration 5 × 105 cells/well) in a round plate bound with 48 wells. Later, PBMC was collected for analysis by flow cytometry, with the monoclonal antibodies αCD14, αCD4, αCD8, αCD19 and αFoxp3, and acquired using an FACSCanto II cytometer. The supernatant of cellular cultures was analyzed for the quantification of inflammatory cytokines. Data analysis was performed in FlowJo v10.8.2 and FCAPArray software, and statistical analysis was performed using GraphPad v5.0. software. We observed an increase in the percentage of CD14+ cells in patients at different hours of cellular culture in the presence of both Actinomyces spp. and Streptococcus spp. microorganisms, compared to healthy controls. This study demonstrates the role played by the innate immune system in the pathogeny of endodontic primary infections, explaining the effects that generate the more common microorganisms in this oral pathology.

Increased levels of pathogenic Th17 cells and diminished function of CD69+ Treg lymphocytes in patients with overweight.

A low-grade inflammatory phenomenon is a feature of overweight and metabolic syndrome. The involvement of a pro-inflammatory Th17 lymphocyte subset and the CD69+ T regulatory (Treg) cell subtype in patients with metabolic dysfunction associated with or without overweight has not been fully elucidated. The aim of this study was to perform a quantitative and functional analysis of pathogenic Th17 lymphocytes and CD69+ Treg cells in patients with metabolic dysfunction (insulin resistance and dyslipidemia). The number of pathogenic Th17 cells and the levels and function of CD69+ Treg cells were analyzed in blood samples from individuals with metabolic dysfunction, associated with or without overweight. Pathogenic and non-pathogenic Th17 lymphocytes as well as Th22 cells were determined by eight-color flow cytometry analysis, whereas the levels and suppressive function of CD69+ Treg cells were also analyzed by multiparametric flow cytometry. We detected increased levels of pro-inflammatory Th17 pathogenic cells and Th22 lymphocytes in overweight unhealthy individuals (P < 0.001, compared to normal weight healthy). Conversely, diminished numbers of CD69+ Treg lymphocytes were observed in metabolically unhealthy individuals, with or without overweight. Likewise, the immunosuppressive function of CD69+ Treg cells was also defective in these patients. The increased levels of pathogenic Th17 cells along with a diminished number and function of CD69+ Treg lymphocytes may significantly contribute to the low-grade inflammatory phenomenon of metabolically unhealthy patients.

Quantitative and Functional Analysis of PD-1+ NK Cells in Patients With Autoimmune Thyroid Disease.

CONTEXT: Natural killer (NK) cells have an important role in innate immunity and in the regulation of immune response. The role of NK cells expressing the programmed cell death protein-1 (PD-1) regulatory receptor has not been explored in patients with autoimmune thyroid disease (AITD). PURPOSE: To analyze the levels and function of PD-1+ NK cells in samples from AITD patients. DESIGN: Cases and controls, observational study. SETTING: Hospital Universitario la Princesa, Spain. PATIENTS: Forty patients with AITD, 16 with Hashimoto thyroiditis (HT), 24 with Graves' disease (GD), and 15 healthy controls. INTERVENTION: Multiparametric flow cytometry analysis of peripheral blood NK cells. In vitro assays of cytotoxic activity of NK cells, and synthesis of cytokines. MAIN OUTCOME MEASURES: Levels and function of PD-1+ NK cells in blood samples from AITD patients and controls. RESULTS: Increased levels of NK cells and the CD56dimPD-1+ subset were observed in GD patients. In HT, an enhanced expression of the regulatory receptors NKG2A and NKG2C by CD56brightPD-1+ NK cells was detected. AITD patients showed an increased synthesis of IL-10 by CD56brightPD-1- NK cells, whereas CD56dimPD-1+ cells from GD patients exhibited an enhanced production of interferon-γ. PD-1+ NK cells from patients with GD and HT showed an increased cytotoxic activity. Significant associations were observed in patients with GD or HT between the levels of PD-1+ NK cells and clinical laboratory parameters. CONCLUSIONS: The different abnormalities in NK cell subset levels, in the expression of PD-1 and its function in AITD patients' further support the complex role of these cells in this pathogenesis.