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In this study, we synthesized a novel ceramic material Bi0.5Na0.5Ti0.95 (Ni0.2Fe0.2Sb0.6)0.05O3 named BNT-NFS via the solid-state route and assessed its efficacy as a photocatalyst for removing methylene blue dye from wastewater. The synthesized samples underwent thorough characterization using thermogravimetric analysis combined differential thermal analysis TGA-TDA, X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET) analysis, and UV–Visible measurements. TGA-DTA and XRD analyses confirmed the successful formation of BNT-NFS material at 1150 °C, exhibiting a hexagonal phase structure. FTIR analysis revealed an intense band at 421 cm−1, corresponding to metal-oxide vibrations in the BNT-NFS spectrum. SEM observations unveiled a distinct microstructure of BNT-NFS composed of grains of varying sizes. BET analysis indicated that the prepared BNT-NFS powder possessed a significant specific surface area of 261.36 m2/g. Optical and photocatalytic assessments demonstrated that BNF-NFS perovskite is a semiconductor material with a band gap of 2.73 eV, exhibiting satisfactory photocatalytic activity for methylene blue MB dye removal. Notably, the removal efficiency reached 60% after 210 min of exposure to sunlight irradiation. This result is better than that registered for the pristine BNT. [ABSTRACT FROM AUTHOR]

A diverse T cell receptor (TCR) repertoire is essential for protection against a variety of pathogens, and TCR repertoire size is believed to decline with age. However, the precise size of human TCR repertoires, in both total and subsets of T cells, as well as their changes with age, are not fully characterized. We conducted a longitudinal analysis of the human blood TCR[alpha] and TCR[beta] repertoire of [CD4.sup.+] and [CD8.sup.+] T cell subsets using a unique molecular identifier-based (UMI-based) RNA-seq method. Thorough analysis of 1.9 x [10.sup.8] T cells yielded the lower estimate of TCR repertoire richness in an adult at 3.8 x [10.sup.8]. Alterations of the TCR repertoire with age were observed in all 4 subsets of T cells. The greatest reduction was observed in naive [CD8.sup.+] T cells, while the greatest clonal expansion was in memory [CD8.sup.+] T cells, and the highest increased retention of TCR sequences was in memory [CD8.sup.+] T cells. Our results demonstrated that age-related TCR repertoire attrition is subset specific and more profound for [CD8.sup.+] than [CD4.sup.+] T cells, suggesting that aging has a more profound effect on cytotoxic as opposed to helper T cell functions. This may explain the increased susceptibility of older adults to novel infections., Introduction Naive T cells produced by the thymus have the potential to recognize any pathogen, whereas memory T cells are generated from a past immunological response and offer long-lasting protection [...]

Nanoparticles of pure and co-doped according to the formula Ca1−yCeyFe1−xMgxO3−δ (x = y = 0.0, y = 0.1; x = 0.0, 0.1, 0.2) have been successfully synthesized through a wet chemical sol–gel method using citric acid as a chelating agent. So, the prepared materials after calcination at 800 °C for 6 h were examined for structural, optical, and photocatalytic properties using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (IRTF), and ultraviolet–visible spectrophotometer (UV–Vis). The X-ray diffraction measurements of all the compositions confirm the formation of a single-phase orthorhombic perovskite-related structure, with a Pcmn space group without any other heterogeneity or structural transition. The crystallite size is found to decrease with increasing Mg2+ doping in Ca0.9Ce0.1Fe1−xMgxO3−δ. The results of the FTIR analysis confirmed the presence of the typical band characteristics of metal oxygen bonds, which are features of FeO6 octaedra in the oxide perovskite materials. UV–Vis optical spectra revealed that the band gap of pure CaFeO3−δ observed in the visible range was tuned by doping Ce3+ and Mg2+, which has improved the photodegradation efficiency and kinetic degradation rates of methylene blue under sunlight irradiation. The possible mechanism of the photocatalytic activity is also proposed in this contribution. [ABSTRACT FROM AUTHOR]

The decline of CD8+ T cell functions contributes to deteriorating health with aging, but the mechanisms that underlie this phenomenon are not well understood. We use single-cell RNA sequencing with both cross-sectional and longitudinal samples to assess how human CD8+ T cell heterogeneity and transcriptomes change over nine decades of life. Eleven subpopulations of CD8+ T cells and their dynamic changes with age are identified. Age-related changes in gene expression result from changes in the percentage of cells expressing a given transcript, quantitative changes in the transcript level, or a combination of these two. We develop a machine learning model capable of predicting the age of individual cells based on their transcriptomic features, which are closely associated with their differentiation and mutation burden. Finally, we validate this model in two separate contexts of CD8+ T cell aging: HIV infection and CAR T cell expansion in vivo. The characterisation of T cells during aging is important to predict functional outcomes in vaccination or infection. Here the authors use flow cytometry and scRNA sequencing to transcriptionally age CD8 T cells and then use a machine learning model to interpret cell age from transcriptional profiles. [ABSTRACT FROM AUTHOR]

Background Follicular helper T (T FH ) cells support terminal B-cell differentiation. Human regulatory B (Breg) cells modulate cellular responses, but their control of T FH cell–dependent humoral immune responses is unknown. Objective We sought to assess the role of Breg cells on T FH cell development and function. Methods Human T cells were polyclonally stimulated in the presence of IL-12 and IL-21 to generate T FH cells. They were cocultured with B cells to induce their terminal differentiation. Breg cells were included in these cultures, and their effects were evaluated by using flow cytometry and ELISA. Results B-cell lymphoma 6, IL-21, inducible costimulator, CXCR5, and programmed cell death protein 1 (PD-1) expressions increased on stimulated human T cells, characterizing T FH cell maturation. In cocultures they differentiated B cells into CD138 + plasma and IgD − CD27 + memory cells and triggered immunoglobulin secretions. Breg cells obtained by Toll-like receptor 9 and CD40 activation of B cells prevented T FH cell development. Added to T FH cell and B-cell cocultures, they inhibited B-cell differentiation, impeded immunoglobulin secretions, and expanded Foxp3 + CXCR5 + PD-1 + follicular regulatory T cells. Breg cells modulated IL-21 receptor expressions on T FH cells and B cells, and their suppressive activities involved CD40, CD80, CD86, and intercellular adhesion molecule interactions and required production of IL-10 and TGF-β. Conclusion Human Breg cells control T FH cell maturation, expand follicular regulatory T cells, and inhibit the T FH cell–mediated antibody secretion. These novel observations demonstrate a role for the Breg cell in germinal center reactions and suggest that deficient activities might impair the T FH cell–dependent control of humoral immunity and might lead to the development of aberrant autoimmune responses. [ABSTRACT FROM AUTHOR]

Background. Anti- Saccharomyces cerevisiae antibodies (ASCA) had been known to be specific for Crohn's disease, but they had also been found in many other autoimmune diseases. Aim. The aim of this study was to evaluate the prevalence of ASCA in patients with autoimmune thyroid disease (AITD). Patients and Methods. One hundred and ninety-seven patients with AITD and 160 healthy controls were included in the study. One hundred and nineteen patients had Graves' disease (GD) and 78 patients had Hashimoto's thyroiditis (HT). ASCA IgG and IgA were determined by ELISA. Results. ASCA IgG were significantly more frequent in patients with GD than in control group (11.8% vs. 3.1%, p = 0.002). In HT, the frequency of ASCA IgG was similar to that of the control group (3.8% and 3.1% respectively). The frequency of ASCA IgA was similar in GD (0.8%), HT (2.6%), and the control group (3.1%). In all GD patients, the frequency of ASCA IgG was significantly higher than that of ASCA IgA (11.8% vs. 0.8%, p = 0.001). These results were also true even in male and female groups (10.4% vs. 1.3%, p = 0.01 and 14.3% vs. 0%, p = 0.01, respectively). ASCA IgG levels were significantly higher in GD patients (6.7 ± 11.1 vs. 2.2 ± 2.8, p = 3 × 10−6) and in HT patients (4.2 ± 4.7 vs. 2.2 ± 2.8, p = 0.0002) than those in the control group. ASCA IgA levels were comparable among patients with GD, HT, and the control group. In GD patients, the mean titer of ASCA IgG was significantly higher than that of ASCA IgA (6.7 ± 11.1 vs. 3.6 ± 4.2, p = 0.005). Conclusion. Patients with GD had a higher frequency of ASCA IgG than controls. [ABSTRACT FROM AUTHOR]

Aim. To evaluate, retrospectively, the frequency of antithyroid antibodies (ATA) in patients with type 1 diabetes (T1D). Materials and methods. Antithyroperoxidase antibodies (TPO-Ab), antithyroglobulin antibodies (TG-Ab), and antithyroid-stimulating hormone receptor antibodies (TSHR-Ab) were determined by enzyme-linked immunosorbent assay. Sera of 312 patients (166 children and 146 adults) with T1D were analyzed. Sera of 276 healthy subjects (87 children and 189 blood donors) served as controls. Results. Out of 312 patients with T1D, 44 (14%%) had ATA (TPO-Ab or TG-Ab or TSHR-Ab). The frequency of ATA in patients with T1D was significantly higher than in the control group (14%% vs. 2.8%%; p < 10−5). ATA were significantly more frequent in adult patients with T1D than in the blood donor group (20%% vs. 1.6%%; p < 10−8). The frequency of ATA in adult patients was significantly higher than in pediatric patients (20%% vs. 9%%; p == 0.006). The frequency of TPO-Ab and TG-Ab was significantly higher in patients with T1D than in the control group (13.5%% vs. 2%%; p < 10−8 and 7%% vs. 2.2%%, p == 0.008), respectively. Out of 312 patients with T1D, only one had TSHR-Ab. The simultaneous presence of three autoantibodies was found in one patient with T1D. Conclusion. ATA were frequent in patients with T1D. Serological screening of autoimmune thyroid disease is suggested in patients with T1D. [ABSTRACT FROM AUTHOR]

A diverse T cell receptor (TCR) repertoire is essential for protection against a variety of pathogens, and TCR repertoire size is believed to decline with age. However, the precise size of human TCR repertoires, in both total and subsets of T cells, as well as their changes with age, are not fully characterized. We conducted a longitudinal analysis of the human blood TCRα and TCRβ repertoire of CD4+ and CD8+ T cell subsets using a unique molecular identifier-based (UMI-based) RNA-seq method. Thorough analysis of 1.9 × 108 T cells yielded the lower estimate of TCR repertoire richness in an adult at 3.8 × 108. Alterations of the TCR repertoire with age were observed in all 4 subsets of T cells. The greatest reduction was observed in naive CD8+ T cells, while the greatest clonal expansion was in memory CD8+ T cells, and the highest increased retention of TCR sequences was in memory CD8+ T cells. Our results demonstrated that age-related TCR repertoire attrition is subset specific and more profound for CD8+ than CD4+ T cells, suggesting that aging has a more profound effect on cytotoxic as opposed to helper T cell functions. This may explain the increased susceptibility of older adults to novel infections. [ABSTRACT FROM AUTHOR]

Thymic regulatory T cells (tTreg) are critical in the maintenance of normal T cell immunity and tolerance. The role of TCR in tTreg selection remains incompletely understood. In this study, we assessed TCRα and TCRβ sequences of mouse tTreg and thymic conventional CD4+ T cells (Tconv) by high-throughput sequencing. We identified αβ TCR sequences that were unique to either tTreg or Tconv and found that these were distinct as recognized by machine learning algorithm and by preferentially used amino acid trimers in αβ CDR3 of tTreg. In addition, a proportion of αβ TCR sequences expressed by tTreg were also found in Tconv, and machine learning classified the great majority of these shared αβ TCR sequences as characteristic of Tconv and not tTreg. These findings identify two populations of tTreg, one in which the regulatory T cell fate is associated with unique properties of the TCR and another with TCR properties characteristic of Tconv for which tTreg fate is determined by factors beyond TCR sequence. [ABSTRACT FROM AUTHOR]

Mechanims of peripheral tolerance include molecular controls and the presence of regulatory lymphocytes. Regulatory T lymphocytes (Tregs) correspond to different sub-populations of T cells that control immune responses due to the production of cytokines, such as IL-10 and with direct cell-to-cell contacts. Tregs targets are antigen presenting cells, such as dendritic cells, effector CD4(+) and CD8(+) lymphocytes but also effector antibody-producing B lymphocytes. Regulatory B lymphocytes (Bregs) have been more recently described and likely represent different sub-populations of B cells that control the development of autoimmune and inflammatory diseases due to the production of IL-10 and using intercellular contacts. Bregs targets encompass all the cells involved in the immune responses which are thus under a dual control by regulatory lymphocytes. Development and efficient activity of Tregs appear dependent of Bregs for a better regulation of autoimmune reactions, of anti-infectious reactions, but also of anti-tumor reactions., (Copyright © 2013 Elsevier Masson SAS. All rights reserved.)