Antigen-specific B cells direct T follicular-like helper cells into lymphoid follicles to mediate Mycobacterium tuberculosis control.

Tuberculosis (TB), caused by Mycobacterium tuberculosis (Mtb), is a global cause of death. Granuloma-associated lymphoid tissue (GrALT) correlates with protection during TB, but the mechanisms of protection are not understood. During TB, the transcription factor IRF4 in T cells but not B cells is required for the generation of the TH1 and TH17 subsets of helper T cells and follicular helper T (TFH)-like cellular responses. A population of IRF4+ T cells coexpress the transcription factor BCL6 during Mtb infection, and deletion of Bcl6 (Bcl6fl/fl) in CD4+ T cells (CD4cre) resulted in reduction of TFH-like cells, impaired localization within GrALT and increased Mtb burden. In contrast, the absence of germinal center B cells, MHC class II expression on B cells, antibody-producing plasma cells or interleukin-10-expressing B cells, did not increase Mtb susceptibility. Indeed, antigen-specific B cells enhance cytokine production and strategically localize TFH-like cells within GrALT via interactions between programmed cell death 1 (PD-1) and its ligand PD-L1 and mediate Mtb control in both mice and macaques.

Defining inflammatory cell states in rheumatoid arthritis joint synovial tissues by integrating single-cell transcriptomics and mass cytometry.

To define the cell populations that drive joint inflammation in rheumatoid arthritis (RA), we applied single-cell RNA sequencing (scRNA-seq), mass cytometry, bulk RNA sequencing (RNA-seq) and flow cytometry to T cells, B cells, monocytes, and fibroblasts from 51 samples of synovial tissue from patients with RA or osteoarthritis (OA). Utilizing an integrated strategy based on canonical correlation analysis of 5,265 scRNA-seq profiles, we identified 18 unique cell populations. Combining mass cytometry and transcriptomics revealed cell states expanded in RA synovia: THY1(CD90)+HLA-DRAhi sublining fibroblasts, IL1B+ pro-inflammatory monocytes, ITGAX+TBX21+ autoimmune-associated B cells and PDCD1+ peripheral helper T (TPH) cells and follicular helper T (TFH) cells. We defined distinct subsets of CD8+ T cells characterized by GZMK+, GZMB+, and GNLY+ phenotypes. We mapped inflammatory mediators to their source cell populations; for example, we attributed IL6 expression to THY1+HLA-DRAhi fibroblasts and IL1B production to pro-inflammatory monocytes. These populations are potentially key mediators of RA pathogenesis.

Deconstruction of rheumatoid arthritis synovium defines inflammatory subtypes.

Rheumatoid arthritis is a prototypical autoimmune disease that causes joint inflammation and destruction1. There is currently no cure for rheumatoid arthritis, and the effectiveness of treatments varies across patients, suggesting an undefined pathogenic diversity1,2. Here, to deconstruct the cell states and pathways that characterize this pathogenic heterogeneity, we profiled the full spectrum of cells in inflamed synovium from patients with rheumatoid arthritis. We used multi-modal single-cell RNA-sequencing and surface protein data coupled with histology of synovial tissue from 79 donors to build single-cell atlas of rheumatoid arthritis synovial tissue that includes more than 314,000 cells. We stratified tissues into six groups, referred to as cell-type abundance phenotypes (CTAPs), each characterized by selectively enriched cell states. These CTAPs demonstrate the diversity of synovial inflammation in rheumatoid arthritis, ranging from samples enriched for T and B cells to those largely lacking lymphocytes. Disease-relevant cell states, cytokines, risk genes, histology and serology metrics are associated with particular CTAPs. CTAPs are dynamic and can predict treatment response, highlighting the clinical utility of classifying rheumatoid arthritis synovial phenotypes. This comprehensive atlas and molecular, tissue-based stratification of rheumatoid arthritis synovial tissue reveal new insights into rheumatoid arthritis pathology and heterogeneity that could inform novel targeted treatments.

Publisher Correction: Group 3 innate lymphoid cells mediate early protective immunity against tuberculosis.

An Amendment to this paper has been published and can be accessed via a link at the top of the paper.

Group 3 innate lymphoid cells mediate early protective immunity against tuberculosis.

Tuberculosis is the leading cause of death by an infectious disease worldwide1. However, the involvement of innate lymphoid cells (ILCs) in immune responses to infection with Mycobacterium tuberculosis (Mtb) is unknown. Here we show that circulating subsets of ILCs are depleted from the blood of participants with pulmonary tuberculosis and restored upon treatment. Tuberculosis increased accumulation of ILC subsets in the human lung, coinciding with a robust transcriptional response to infection, including a role in orchestrating the recruitment of immune subsets. Using mouse models, we show that group 3 ILCs (ILC3s) accumulated rapidly in Mtb-infected lungs and coincided with the accumulation of alveolar macrophages. Notably, mice that lacked ILC3s exhibited a reduction in the accumulation of early alveolar macrophages and decreased Mtb control. We show that the C-X-C motif chemokine receptor 5 (CXCR5)-C-X-C motif chemokine ligand 13 (CXCL13) axis is involved in Mtb control, as infection upregulates CXCR5 on circulating ILC3s and increases plasma levels of its ligand, CXCL13, in humans. Moreover, interleukin-23-dependent expansion of ILC3s in mice and production of interleukin-17 and interleukin-22 were found to be critical inducers of lung CXCL13, early innate immunity and the formation of protective lymphoid follicles within granulomas. Thus, we demonstrate an early protective role for ILC3s in immunity to Mtb infection.

Fermionic wave functions from neural-network constrained hidden states.

We introduce a systematically improvable family of variational wave functions for the simulation of strongly correlated fermionic systems. This family consists of Slater determinants in an augmented Hilbert space involving "hidden" additional fermionic degrees of freedom. These determinants are projected onto the physical Hilbert space through a constraint that is optimized, together with the single-particle orbitals, using a neural network parameterization. This construction draws inspiration from the success of hidden-particle representations but overcomes the limitations associated with the mean-field treatment of the constraint often used in this context. Our construction provides an extremely expressive family of wave functions, which is proved to be universal. We apply this construction to the ground-state properties of the Hubbard model on the square lattice, achieving levels of accuracy that are competitive with those of state-of-the-art variational methods.

Phospholipase C epsilon-1 (PLCƐ1) mediates macrophage activation and protection against tuberculosis.

Tuberculosis (TB) caused by Mycobacterium tuberculosis (Mtb) infects up to a quarter of the world's population. Although immune responses can control Mtb infection, 5%-10% of infected individuals can progress to active TB disease (progressors). A myriad of host factors regulate disease progression in TB and a better understanding of immune correlates of protection and disease is pivotal for the development of new therapeutics. Comparison of human whole blood transcriptomic metadata with that of macaque TB progressors and Mtb-infected diversity outbred mice (DO) led to the identification of differentially regulated gene (DEG) signatures, associated with TB progression or control. The current study assessed the function of Phospholipase C epsilon (PLCƐ1), the top downregulated gene across species in TB progressors, using a gene-specific knockout mouse model of Mtb infection and in vitro Mtb-infected bone marrow-derived macrophages. PLCƐ1 gene expression was downregulated in TB progressors across species. PLCε1 deficiency in the mouse model resulted in increased susceptibility to Mtb infection, coincident accumulation of lung myeloid cells, and reduced ability to mount antibacterial responses. However, PLCε1 was not required for the activation and accumulation of T cells in mice. Our results suggest an important early role for PLCƐ1 in shaping innate immune response to TB and may represent a putative target for host-directed therapy.

Recurrent bacteremia and endocarditis due to Staphylococcus capitis in a patient with Bowen's disease: a case report.

This case report details the management of a 79-year-old male with recurrent methicillin-resistant Staphylococcus capitis bacteremia and endocarditis. The patient's clinical journey encompassed multiple hospital admissions, with challenges in managing endocarditis, pacemaker replacements, and potential cutaneous sources of infection. The treatment regimen included intravenous antibiotic therapy during hospitalization and suppressive antibiotic treatment upon discharge, alongside a decolonization strategy for his scalp lesions.

Portable smartphone-based molecular test for rapid detection of Leishmania spp.

PURPOSE: Leishmaniasis, caused by the parasite of the genus Leishmania, is a neglected tropical disease which is endemic in more than 60 countries. In South-East Asia, Brazil, and East Africa, it mainly occurs as kala-azar (visceral leishmaniasis, VL), and subsequently as post kala-azar dermal leishmaniasis (PKDL) in a smaller portion of cases. As stated per WHO roadmap, accessibility to accurate diagnostic methods is an essential step to achieve elimination. This study aimed to test the accuracy of a portable minoo device, a small battery-driven, multi-use fluorimeter operating with isothermal technology for molecular diagnosis of VL and PKDL. METHODS: Fluorescence data measured by the device within 20 min are reported back to the mobile application (or app) via Bluetooth and onward via the internet to a backend. This allows anonymous analysis and storage of the test data. The test result is immediately returned to the app displaying it to the user. RESULTS: The limit of detection was 11.2 genome copies (95% CI) as determined by screening a tenfold dilution range of whole Leishmania donovani genomes using isothermal recombinase polymerase amplification (RPA). Pathogens considered for differential diagnosis were tested and no cross-reactivity was observed. For its diagnostic performance, DNA extracted from 170 VL and PKDL cases, comprising peripheral blood samples (VL, n = 96) and skin biopsies (PKDL, n = 74) from India (n = 108) and Bangladesh (n = 62), was screened. Clinical sensitivity and specificity were 88% and 91%, respectively. CONCLUSION: Minoo devices can offer a convenient, cheaper alternative to other molecular diagnostics. Its easy handling makes it ideal for use in low-resource settings to identify parasite burden.

Near-field detection and peak frequency metric for substrate and activation mapping of ventricular tachycardias in two- and three-dimensional circuits.

AIMS: Successful ventricular arrhythmia (VA) ablation requires identification of functionally critical sites during contact mapping. Estimation of the peak frequency (PF) component of the electrogram (EGM) may improve correct near-field (NF) annotation to identify circuit segments on the mapped surface. In turn, assessment of NF and far-field (FF) EGMs may delineate the three-dimensional path of a ventricular tachycardia (VT) circuit. METHODS AND RESULTS: A proprietary NF detection algorithm was applied retrospectively to scar-related re-entry VT maps and compared with manually reviewed maps employing first deflection (FDcorr) for VT activation maps and last deflection (LD) for substrate maps. Ventricular tachycardia isthmus location and characteristics mapped with FDcorr vs. NF were compared. Omnipolar low-voltage areas, late activating areas, and deceleration zones (DZ) in LD vs. NF substrate maps were compared. On substrate maps, PF estimation was compared between isthmus and bystander sites. Activation mapping with entrainment and/or VT termination with radiofrequency (RF) ablation confirmed critical sites. Eighteen patients with high-density VT activation and substrate maps (55.6% ischaemic) were included. Near-field detection correctly located critical parts of the circuit in 77.7% of the cases compared with manually reviewed VT maps as reference. In substrate maps, NF detection identified deceleration zones in 88.8% of cases, which overlapped with FDcorr VT isthmus in 72.2% compared with 83.3% overlap of DZ assessed by LD. Applied to substrate maps, PF as a stand-alone feature did not differentiate VT isthmus sites from low-voltage bystander sites. Omnipolar voltage was significantly higher at isthmus sites with longer EGM durations compared with low-voltage bystander sites. CONCLUSION: The NF algorithm may enable rapid high-density activation mapping of VT circuits in the NF of the mapped surface. Integrated assessment and combined analysis of NF and FF EGM-components could support characterization of three-dimensional VT circuits with intramural segments. For scar-related substrate mapping, PF as a stand-alone EGM feature did not enable the differentiation of functionally critical sites of the dominant VT from low-voltage bystander sites in this cohort.

Experimental Tumor Induction and Evaluation of Its Treatment in the Chicken Embryo Chorioallantoic Membrane Model: A Systematic Review.

The chorioallantoic membrane (CAM) model, generated during avian development, can be used in cancer research as an alternative in vivo model to perform tumorigenesis in ovo due to advantages such as simplicity, low cost, rapid growth, and being naturally immunodeficient. The aim of this systematic review has been to compile and analyze all studies that use the CAM assay as a tumor induction model. For that, a systematic search was carried out in four different databases: PubMed, Scopus, Cochrane, and WOS. After eliminating duplicates and following the established inclusion and exclusion criteria, a total of 74 articles were included. Of these, 62% use the in ovo technique, 13% use the ex ovo technique, 9% study the formation of metastasis, and 16% induce tumors from patient biopsies. Regarding the methodology followed, the main species used is chicken (95%), although some studies use quail eggs (4%), and one article uses ostrich eggs. Therefore, the CAM assay is a revolutionary technique that allows a simple and effective way to induce tumors, test the effectiveness of treatments, carry out metastasis studies, perform biopsy grafts of patients, and carry out personalized medicine. However, unification of the methodology used is necessary.

Transcriptomic Analysis of Extracellular Vesicles in the Search for Novel Plasma and Thrombus Biomarkers of Ischemic Stroke Etiologies.

Accurate etiologic diagnosis provides an appropriate secondary prevention and better prognosis in ischemic stroke (IS) patients; still, 45% of IS are cryptogenic, urging us to enhance diagnostic precision. We have studied the transcriptomic content of plasma extracellular vesicles (EVs) (n = 21) to identify potential biomarkers of IS etiologies. The proteins encoded by the selected genes were measured in the sera of IS patients (n = 114) and in hypertensive patients with (n = 78) and without atrial fibrillation (AF) (n = 20). IGFBP-2, the most promising candidate, was studied using immunohistochemistry in the IS thrombi (n = 23) and atrium of AF patients (n = 13). In vitro, the IGFBP-2 blockade was analyzed using thromboelastometry and endothelial cell cultures. We identified 745 differentially expressed genes among EVs of cardioembolic, atherothrombotic, and ESUS groups. From these, IGFBP-2 (cutoff > 247.6 ng/mL) emerged as a potential circulating biomarker of embolic IS [OR = 8.70 (1.84-41.13) p = 0.003], which was increased in patients with AF vs. controls (p < 0.001) and was augmented in cardioembolic vs. atherothrombotic thrombi (p < 0.01). Ex vivo, the blockage of IGFBP-2 reduced clot firmness (p < 0.01) and lysis time (p < 0.001) and in vitro, diminished endothelial permeability (p < 0.05) and transmigration (p = 0.06). IGFBP-2 could be a biomarker of embolic IS and a new therapeutic target involved in clot formation and endothelial dysfunction.

The development of inducible bronchus-associated lymphoid tissue depends on IL-17.

Ectopic or tertiary lymphoid tissues, such as inducible bronchus-associated lymphoid tissue (iBALT), form in nonlymphoid organs after local infection or inflammation. However, the initial events that promote this process remain unknown. Here we show that iBALT formed in mouse lungs as a consequence of pulmonary inflammation during the neonatal period. Although we found CD4(+)CD3(-) lymphoid tissue-inducer cells (LTi cells) in neonatal lungs, particularly after inflammation, iBALT was formed in mice that lacked LTi cells. Instead, we found that interleukin 17 (IL-17) produced by CD4(+) T cells was essential for the formation of iBALT. IL-17 acted by promoting lymphotoxin-α-independent expression of the chemokine CXCL13, which was important for follicle formation. Our results suggest that IL-17-producing T cells are critical for the development of ectopic lymphoid tissues.

Automatic identification of areas with low-voltage fragmented electrograms for the detection of the critical isthmus of atypical atrial flutters.

INTRODUCTION: Critical isthmuses of atypical atrial flutters (AAFLs) are usually located at slow conduction areas that exhibit fractionated electrograms. We tested a novel software, intended for integration with a commercially available navigation system, that automatically detects fractionated electrograms, to identify the critical isthmus in patients with AAFL ablation. METHODS AND RESULTS: All available patients were analyzed; 27 patients with 33 AAFLs were included. The PentaRay NAV catheter (Biosense Webster) was used for mapping. The novel software was retrospectively applied; fractionated points with duration ≥80 ms and bipolar voltage between 0.05 and 0.5 mV were highlighted on the surface of maps. In 10 randomly chosen AAFLs, an expert electrophysiologist evaluated the positive predictive value of the algorithm to detect true fractionation: 74.4%. We tested the capacity of the software to identify areas of fractionation (defined as clusters of ≥3 adjacent points with fractionation) at the critical isthmus of the AAFLs (defined using conventional mapping criteria). An area of fractionation was identified at the critical isthmus in 30 cases (91%). Globally, 144 areas of fractionation (median number per AAFL 4 [3-6]) were identified. Duration of the fractionation or the surface of the areas was not different between areas at critical isthmuses and the rest. Setting the fractionation score filter of the software in nine provided best performance. CONCLUSIONS: The novel software detected areas of fractionation at the critical isthmus in most AAFLs, which may help identify the critical isthmus in clinical practice.

Impact of different activation wavefronts on ischemic myocardial scar electrophysiological properties during high-density ventricular tachycardia mapping and ablation.

INTRODUCTION: Scar-related ventricular tachycardia (VT) usually results from an underlying reentrant circuit facilitated by anatomical and functional barriers. The later are sensitive to the direction of ventricular activation wavefronts. We aim to evaluate the impact of different ventricular activation wavefronts on the functional electrophysiological properties of myocardial tissue. METHODS: Patients with ischemic heart disease referred for VT ablation underwent high-density mapping using Carto®3 (Biosense Webster). Maps were generated during sinus rhythm, right and left ventricular pacing, and analyzed using a new late potential map software, which allows to assess local conduction velocities and facilitates the delineation of intra-scar conduction corridors (ISCC); and for all stable VTs. RESULTS: In 16 patients, 31 high-resolution substrate maps from different ventricular activation wavefronts and 7 VT activation maps were obtained. Local abnormal ventricular activities (LAVAs) were found in VT isthmus, but also in noncritical areas. The VT isthmus was localized in areas of LAVAs overlapping surface between the different activation wavefronts. The deceleration zone location differed depending on activation wavefronts. Sixty-six percent of ISCCs were similarly identified in all activating wavefronts, but the one acting as VT isthmus was simultaneously identified in all activation wavefronts in all cases. CONCLUSION: Functional based substrate mapping may improve the specificity to localize the most arrhythmogenic regions within the scar, making the use of different activation wavefronts unnecessary in most cases.

Conformal Bounds in Three Dimensions from Entanglement Entropy.

The entanglement entropy of an arbitrary spacetime region A in a three-dimensional conformal field theory (CFT) contains a constant universal coefficient, F(A). For general theories, the value of F(A) is minimized when A is a round disk, F_{0}, and in that case it coincides with the Euclidean free energy on the sphere. We conjecture that, for general CFTs, the quantity F(A)/F_{0} is bounded above by the free scalar field result and below by the Maxwell field one. We provide strong evidence in favor of this claim and argue that an analogous conjecture in the four-dimensional case is equivalent to the Hofman-Maldacena bounds. In three dimensions, our conjecture gives rise to similar bounds on the quotients of various constants characterizing the CFT. In particular, it implies that the quotient of the stress-tensor two-point function coefficient and the sphere free energy satisfies C_{T}/F_{0}≤3/(4π^{2}log2-6ζ[3])≃0.14887 for general CFTs. We verify the validity of this bound for free scalars and fermions, general O(N) and Gross-Neveu models, holographic theories, N=2 Wess-Zumino models and general ABJM theories.

Rapid synthesis of auxin via a new tryptophan-dependent pathway is required for shade avoidance in plants.

Plants grown at high densities perceive a decrease in the red to far-red (R:FR) ratio of incoming light, resulting from absorption of red light by canopy leaves and reflection of far-red light from neighboring plants. These changes in light quality trigger a series of responses known collectively as the shade avoidance syndrome. During shade avoidance, stems elongate at the expense of leaf and storage organ expansion, branching is inhibited, and flowering is accelerated. We identified several loci in Arabidopsis, mutations in which lead to plants defective in multiple shade avoidance responses. Here we describe TAA1, an aminotransferase, and show that TAA1 catalyzes the formation of indole-3-pyruvic acid (IPA) from L-tryptophan (L-Trp), the first step in a previously proposed, but uncharacterized, auxin biosynthetic pathway. This pathway is rapidly deployed to synthesize auxin at the high levels required to initiate the multiple changes in body plan associated with shade avoidance.

Effect of Zinc Oxide Nanoparticles on Biomass and Photosynthetic Pigments in Avena sativa.

The nanotechnology applications in agricultural systems are multiple since they offer the potential to significantly improve plant development as well as reduce economic and environmental costs. Zinc oxide nanoparticles (NpsZnO) and other metals have been shown to have positive effects in this field. In this work, NpsZnO were synthesized and their impact on the Avena sativa plant was evaluated. The synthesis of nanoparticles (NPs) was carried out using the sol-gel method and the application of these was carried out in the seeds prior to their sowing. The results indicate that mesoporous NPs were obtained. The results indicated that the plants exposed to the application of NpsZnO had a significantly higher biomass production compared to the control treatment plants, showing values ​​of up to 0.45 (g) compared to the control that contained an average of 0.2 g an increase in the chlorophyll index was observed, obtaining concentrations up to 4 times the control. The growth-promoting effect of the applied NPs could be due to the activity of zinc as a precursor in the synthesis of auxins that promote cell division and elongation.

Effect of Multi-walled Carbon Nanotubes and Manganese and Zinc Doped Ferrites on the Development of Capsicum annuum.

Nanotechnology applied to agriculture (nanoagriculture) represents a watershed in the study and development of novel alternatives that could strongly influence agricultural practices. In this research, we documented the comparative study with multi-walled carbon nanotube (MWCNT) and ferrites doped with zinc-manganese in C. annuum development, due to the nanoparticles study in plant crops has been showing beneficial effects.

Effect of Multi-walled Carbon Nanotubes Functionalized with Indol-3-butyric Acid on the Development of Avena sativa.

In pioneering research, it has been documented that the CNT influences the development of plants through the balance of phytoregulators. Therefore, in this work the objective is to evaluate the effects of CNT functionalized by non-covalent method with indole-3-butyric acid that they have on Avena sativa. The CNT was characterized by FTIR and Raman to confirm functionalization. It was observed that in the germination stage the seeds treated with IBA inhibited germination, however, when functionalizing the CNT with IBA it was observed that the CNT is contributing to counteract this inhibition.