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Establishing a nonproductive, quiescent infection within monocytes is essential for the spread of human cytomegalovirus (HCMV). We investigated the mechanisms through which HCMV establishes a quiescent infection in monocytes. US28 is a virally encoded G protein-coupled receptor (GPCR) that is essential for silent infections within cells of the myeloid lineage. We found that preformed US28 was rapidly delivered to monocytes by HCMV viral particles, whereas the de novo synthesis of US28 was delayed for several days. A recombinant mutant virus lacking US28 (US28Δ) was unable to establish a quiescent infection, resulting in a fully productive lytic infection able to produce progeny virus. Infection with US28Δ HCMV resulted in the phosphorylation of the serine and threonine kinase Akt at Ser473 and Thr308, in contrast with the phosphorylation of Akt only at Ser473 after WT viral infection. Inhibiting the dual phosphorylation of Akt prevented the lytic replication of US28Δ, and ectopic expression of a constitutively phosphorylated Akt variant triggered lytic replication of wild-type HCMV. Mechanistically, we found that US28 was necessary and sufficient to attenuate epidermal growth factor receptor (EGFR) signaling induced during the entry of WT virus, which led to the site-specific phosphorylation of Akt at Ser473. Thus, particle-delivered US28 fine-tunes Akt activity by limiting HCMV-induced EGFR activation during viral entry, enabling quiescent infection in monocytes.
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Citomegalovirus , Receptores ErbB , Monocitos , Proteínas Proto-Oncogénicas c-akt , Proteínas Virales , Replicación Viral , Citomegalovirus/fisiología , Citomegalovirus/genética , Citomegalovirus/metabolismo , Humanos , Monocitos/virología , Monocitos/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Proto-Oncogénicas c-akt/genética , Fosforilación , Proteínas Virales/metabolismo , Proteínas Virales/genética , Receptores ErbB/metabolismo , Receptores ErbB/genética , Virión/metabolismo , Virión/genética , Receptores de Quimiocina/metabolismo , Receptores de Quimiocina/genética , Infecciones por Citomegalovirus/metabolismo , Infecciones por Citomegalovirus/virología , Infecciones por Citomegalovirus/genética , Transducción de SeñalRESUMEN
Science is humanity's best insurance against threats from nature, but it is a fragile enterprise that must be nourished and protected. The preponderance of scientific evidence indicates a natural origin for SARS-CoV-2. Yet, the theory that SARS-CoV-2 was engineered in and escaped from a lab dominates media attention, even in the absence of strong evidence. We discuss how the resulting anti-science movement puts the research community, scientific research, and pandemic preparedness at risk.
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Type I and III interferons (IFNs) are robustly induced during infections and protect cells against viral infection. Both type I and III IFNs are also produced at low levels in the thymus at steady state; however, their role in T cell development and immune tolerance is unclear. Here, we found that both type I and III IFNs were constitutively produced by a very small number of AIRE+ murine thymic epithelial cells, independent of microbial stimulation. Antigen-presenting cells were highly responsive to thymic IFNs, and IFNs were required for the activation and maturation of thymic type 1 conventional dendritic cells, macrophages, and B cells. Loss of IFN sensing led to reduced regulatory T cell selection, reduced T cell receptor (TCR) repertoire diversity, and enhanced autoreactive T cell responses to self-antigens expressed during peripheral IFN signaling. Thus, constitutive exposure to IFNs in the thymus is required for generating a tolerant and diverse TCR repertoire.
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Interferones , Ratones Endogámicos C57BL , Timo , Animales , Timo/inmunología , Ratones , Interferones/inmunología , Ratones Noqueados , Receptores de Antígenos de Linfocitos T/inmunología , Linfocitos T/inmunologíaRESUMEN
KLRG1+ CD8 T cells persist for months after clearance of acute infections and maintain high levels of effector molecules, contributing protective immunity against systemic pathogens. Upon secondary infection, these long-lived effector cells (LLECs) are incapable of forming other circulating KLRG1- memory subsets such as central and effector memory T cells. Thus, KLRG1+ memory T cells are frequently referred to as a terminally differentiated population that is relatively short lived. Here, we show that after viral infection of mice, effector cells derived from LLECs rapidly enter nonlymphoid tissues and reduce pathogen burden but are largely dependent on receiving antigen cues from vascular endothelial cells. Single-cell RNA sequencing reveals that secondary memory cells in nonlymphoid tissues arising from either KLRG1+ or KLRG1- memory precursors develop a similar resident memory transcriptional signature. Thus, although LLECs cannot differentiate into other circulating memory populations, they still retain the flexibility to enter tissues and establish residency.
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Memoria Inmunológica , Lectinas Tipo C , Células T de Memoria , Receptores Inmunológicos , Animales , Femenino , Ratones , Linfocitos T CD8-positivos/inmunología , Memoria Inmunológica/inmunología , Lectinas Tipo C/inmunología , Células T de Memoria/inmunología , Ratones Endogámicos C57BL , Ratones Noqueados , Receptores Inmunológicos/inmunologíaRESUMEN
Vitamins are essential organic compounds that vary widely in chemical structure and are vital in small quantities for numerous biochemical and biological functions. They are critical for metabolism, growth, development and maintaining overall health. Vitamins are categorised into two groups: hydrophilic and lipophilic. Vitamin K (VK), a lipophilic vitamin, occurs naturally in two primary forms: phylloquinone (VK1), found in green leafy vegetables and algae, and Menaquinones (VK2), present in certain fermented and animal foods and widely formulated in VK supplements. This review explores the possible factors contributing to VK deficiency, including dietary influences, and discusses the pharmacological and therapeutic potential of supplementary VK2, examining recent global clinical studies on its role in treating diseases such as osteoporosis, osteoarthritis, rheumatoid arthritis, cardiovascular disease, chronic kidney disease, diabetes, neurodegenerative disorders and cancers. The analysis includes a review of published articles from multiple databases, including Scopus, PubMed, Google Scholar, ISI Web of Science and CNKI, focusing on human studies. The findings indicate that VK2 is a versatile vitamin essential for human health and that a broadly positive correlation exists between VK2 supplementation and improved health outcomes. However, clinical data are somewhat inconsistent, highlighting the need for further detailed research into VK2's metabolic processes, biomarker validation, dose-response relationships, bioavailability and safety. Establishing a Recommended Daily Intake for VK2 could significantly enhance global health.
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Foodborne illnesses can be infectious and dangerous, and most of them are caused by bacteria. Some common food-related bacteria species exist widely in nature and pose a serious threat to both humans and animals; they can cause poisoning, diseases, disabilities and even death. Rapid, reliable and cost-effective methods for bacterial detection are of paramount importance in food safety and environmental monitoring. Polymerase chain reaction (PCR), lateral flow immunochromatographic assay (LFIA) and electrochemical methods have been widely used in food safety and environmental monitoring. In this paper, the recent developments (2013-2023) covering PCR, LFIA and electrochemical methods for various bacterial species (Salmonella, Listeria, Campylobacter, Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli)), considering different food sample types, analytical performances and the reported limit of detection (LOD), are discussed. It was found that the bacteria species and food sample type contributed significantly to the analytical performance and LOD. Detection via LFIA has a higher average LOD (24 CFU/mL) than detection via electrochemical methods (12 CFU/mL) and PCR (6 CFU/mL). Salmonella and E. coli in the Pseudomonadota domain usually have low LODs. LODs are usually lower for detection in fish and eggs. Gold and iron nanoparticles were the most studied in the reported articles for LFIA, and average LODs were 26 CFU/mL and 12 CFU/mL, respectively. The electrochemical method revealed that the average LOD was highest for cyclic voltammetry (CV) at 18 CFU/mL, followed by electrochemical impedance spectroscopy (EIS) at 12 CFU/mL and differential pulse voltammetry (DPV) at 8 CFU/mL. LOD usually decreases when the sample number increases until it remains unchanged. Exponential relations (R2 > 0.95) between LODs of Listeria in milk via LFIA and via the electrochemical method with sample numbers have been obtained. Finally, the review discusses challenges and future perspectives (including the role of nanomaterials/advanced materials) to improve analytical performance for bacterial detection.
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Chronic pain and mental health issues occur at higher rates in Veterans than the general population. One widely recognized mental health issue faced by Veterans is post-traumatic stress disorder (PTSD). Trauma symptoms and pain frequently co-occur and are mutually maintained due to shared mechanisms. Many Veterans are also parents. Parental physical and mental health issues significantly predict children's chronic pain and related functioning, which can continue into adulthood. Only 1 U.S.-based study has examined pain in the offspring of Veterans, suggesting a heightened risk for pain. Research to date has not examined the associations between trauma and pain and the dyadic influences of these symptoms, among Veterans, and their children. The current study aimed to describe pain characteristics in Canadian Armed Forces Members/Veterans with chronic pain and their offspring (youth and adult children aged 9-38). Cross-lagged panel models were conducted to examine dyadic relationships between pain interference and trauma symptoms of Canadian Armed Forces Members/Veterans and their offspring. Over half of adult offspring and over one-quarter of youth offspring reported chronic pain. Results revealed effects between one's own symptoms of PTSD and pain interference. No significant effects of parents on offspring or offspring on parents were found. The findings highlight the interconnection between pain and PTSD consistent with mutual maintenance models and a lack of significant interpersonal findings suggestive of resiliency in this unique population. PERSPECTIVE: We characterized chronic pain in the offspring of Canadian Armed Forces Members/Veterans with chronic pain and examined dyadic relationships between PTSD symptoms and chronic pain interference. Findings revealed that PTSD symptoms and pain interference were related within Veterans and offspring, but no dyadic relationships were found, which could reflect resiliency.
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Hijos Adultos , Dolor Crónico , Personal Militar , Trastornos por Estrés Postraumático , Veteranos , Humanos , Trastornos por Estrés Postraumático/epidemiología , Dolor Crónico/epidemiología , Canadá/epidemiología , Veteranos/estadística & datos numéricos , Femenino , Masculino , Adulto , Niño , Personal Militar/estadística & datos numéricos , Personal Militar/psicología , Adolescente , Adulto Joven , Persona de Mediana EdadRESUMEN
G protein coupled receptors (GPCRs) are seven-transmembrane domain proteins that modulate cellular processes in response to external stimuli. These receptors represent the largest family of membrane proteins, and in mammals, their signaling regulates important physiological functions, such as vision, taste, and olfaction. Many organisms, including yeast, slime molds, and viruses encode GPCRs. Cytomegaloviruses (CMVs) are large, betaherpesviruses, that encode viral GPCRs (vGPCRs). Human CMV (HCMV) encodes four vGPCRs, including UL33, UL78, US27, and US28. Each of these vGPCRs, as well as their rodent and primate orthologues, have been investigated for their contributions to viral infection and disease. Herein, we discuss how the CMV vGPCRs function during lytic and latent infection, as well as our understanding of how they impact viral pathogenesis.
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Infecciones por Citomegalovirus , Receptores Acoplados a Proteínas G , Humanos , Animales , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Transducción de Señal , Citomegalovirus/genética , Infecciones por Citomegalovirus/metabolismo , Mamíferos/metabolismoRESUMEN
Androgen receptor (AR) drives prostate cancer (PC) growth and progression, and targeting AR signaling is the mainstay of pharmacological therapies for PC. Resistance develops relatively fast as a result of refueled AR activity. A major gap in the field is the lack of understanding of targetable mechanisms that induce persistent AR expression in castrate-resistant PC (CRPC). This study uncovers an unexpected function of active Stat5 signaling, a known promoter of PC growth and clinical progression, as a potent inducer of AR gene transcription. Stat5 suppression inhibited AR gene transcription in preclinical PC models and reduced the levels of wild-type, mutated, and truncated AR proteins. Pharmacological Stat5 inhibition by a specific small-molecule Stat5 inhibitor down-regulated Stat5-inducible genes as well as AR and AR-regulated genes and suppressed PC growth. This work introduces the concept of Stat5 as an inducer of AR gene transcription in PC. Pharmacological Stat5 inhibitors may represent a new strategy for suppressing AR and CRPC growth.
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Neoplasias de la Próstata Resistentes a la Castración , Receptores Androgénicos , Masculino , Humanos , Receptores Androgénicos/genética , Receptores Androgénicos/metabolismo , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Neoplasias de la Próstata Resistentes a la Castración/genética , Neoplasias de la Próstata Resistentes a la Castración/metabolismo , Transducción de Señal , Transcripción Genética , Línea Celular Tumoral , Regulación Neoplásica de la Expresión GénicaRESUMEN
Human cytomegalovirus (HCMV) is a prevalent pathogen that establishes life-long latent infection in hematopoietic cells. While this infection is usually asymptomatic, immune dysregulation leads to viral reactivation, which can cause significant morbidity and mortality. However, the mechanisms underpinning reactivation remain incompletely understood. The HCMV major immediate early promoter (MIEP)/enhancer is a key factor in this process, as its transactivation from a repressed to active state helps drive viral gene transcription necessary for reactivation from latency. Numerous host transcription factors bind the MIE locus and recruit repressive chromatin modifiers, thus impeding virus reactivation. One such factor is CCCTC-binding protein (CTCF), a highly conserved host zinc finger protein that mediates chromatin conformation and nuclear architecture. However, the mechanisms by which CTCF contributes to HCMV latency were previously unexplored. Here, we confirm that CTCF binds two convergent sites within the MIE locus during latency in primary CD14+ monocytes, and following cellular differentiation, CTCF association is lost as the virus reactivates. While mutation of the MIE enhancer CTCF binding site does not impact viral lytic growth in fibroblasts, this mutant virus fails to maintain latency in myeloid cells. Furthermore, we show the two convergent CTCF binding sites allow looping to occur across the MIEP, supporting transcriptional repression during latency. Indeed, looping between the two sites diminishes during virus reactivation, concurrent with activation of MIE transcription. Taken together, our data reveal that three-dimensional chromatin looping aids in the regulation of HCMV latency and provides insight into promoter/enhancer regulation that may prove broadly applicable across biological systems.
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Infecciones por Citomegalovirus , Citomegalovirus , Humanos , Cromatina/genética , Citomegalovirus/genética , Infecciones por Citomegalovirus/genética , Regulación Viral de la Expresión Génica , Regiones Promotoras Genéticas , Activación Viral/genética , Latencia del Virus/genéticaRESUMEN
Interpretation of disease-causing genetic variants remains a challenge in human genetics. Current costs and complexity of deep mutational scanning methods hamper crowd-sourcing approaches toward genome-wide resolution of variants in disease-related genes. Our framework, Saturation Mutagenesis-Reinforced Functional assays (SMuRF), addresses these issues by offering simple and cost-effective saturation mutagenesis, as well as streamlining functional assays to enhance the interpretation of unresolved variants. Applying SMuRF to neuromuscular disease genes FKRP and LARGE1, we generated functional scores for over 99.8% of all possible coding single nucleotide variants and resolved 310 clinically reported variants of uncertain significance with high confidence, enhancing clinical variant interpretation in dystroglycanopathies. SMuRF also demonstrates utility in predicting disease severity, resolving critical structural regions, and providing training datasets for the development of computational predictors. Our approach opens new directions for enabling variant-to-function insights for disease genes in a manner that is broadly useful for crowd-sourcing implementation across standard research laboratories.
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In order to safeguard authentic whiskey products from fraudulent or counterfeit practices, high throughput solutions that provide robust, rapid, and reliable solutions are required. The implementation of some analytical strategies is quite challenging or costly in routine analysis. Qualitative screening of whiskey products has been explored, but due to the nonspecificity of the chemical compounds, a more quantitative confirmatory technique is required to validate the result of the whiskey analysis. Hence, combining analytical and chemometric methods has been fundamental in whiskey sample differentiation and classification. A comprehensive update on the most relevant and current analytical techniques, including spectroscopic, chromatographic, and novel technologies employed within the last 5 years in whiskey analysis for authentication, discrimination, and quality control, are presented. Furthermore, the technical challenges in employing these analytical techniques, future trends, and perspectives are emphasized.
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Bebidas Alcohólicas , Bebidas Alcohólicas/análisis , Análisis Espectral , Control de CalidadRESUMEN
Establishing a non-productive quiescent/silent infection within monocytes is essential for spread of human cytomegalovirus (HCMV). Yet, how HCMV establishes a quiescent infection in monocytes remains unclear. US28 is a viral G protein-coupled receptor (GPCR) essential for silent infections within cells of the myeloid lineage. We found virion-associated US28 was rapidly delivered to monocytes, while de novo synthesized US28 was delayed for several days. A recombinant mutant virus lacking US28 (US28Δ) was unable to establish a quiescent infection, resulting in a fully productive lytic replication cycle. Mechanistically, viral entry of US28Δ phosphorylated Akt at both serine 473 (S473) and threonine 308 (T308), which contrasted with the site-specific phosphorylation of Akt at S473 following WT infection. Preventing Akt bi-phosphorylation prevented lytic replication of US28Δ, and ectopic expression of a constitutively phosphorylated Akt variant triggered lytic replication of WT infection. Our data demonstrate that virion-delivered US28 fine-tunes Akt activity to permit HCMV infection to enter a quiescent state following primary infection of monocytes.
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Ga(III) polypyridyl catecholate complexes of type [Ga(bipy)2(O,O)](NO3) or [Ga(phen)2(O,O)](NO3) respectively were readily synthesised on reaction of Ga(NO3)3 in methanol with 1 equivalent of catecholate ligand (2,3-DHBA, 3,4-DHBA, 2,3,4-THBA or CafA) and then 2 equivalents of either bipy or phen. The complexes were characterised in full including by X-ray crystallography, which established that the catecholate ligands coordinate the Ga(III) centres in a bidentate manner via the two deprotonated hydroxy groups. All Ga(III) complexes exhibited good in vitro antibacterial activity against the Gram-negative pathogenic bacteria Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa. The complexes were inactive against the Gram-positive pathogenic bacteria Staphylococcus aureus including against a methicillin-resistant Staphylococcus aureus strain (MRSA). [Ga(bipy)2(2,3-DHBA-2H)](NO3)·1.5H2O (1) was shown to be non toxic in vivo in larvae of Galleria mellonella at doses up to 2000 µg mL-1 and to offer protection at doses of 100 and 250 µg mL-1 at 48 and 96 h to larvae infected with P. aeruginosa.
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Staphylococcus aureus Resistente a Meticilina , Pruebas de Sensibilidad Microbiana , Antibacterianos/química , Staphylococcus aureus , Bacterias Grampositivas , Escherichia coli , Bacterias Gramnegativas , Pseudomonas aeruginosaRESUMEN
Human cytomegalovirus (HCMV) is a betaherpesvirus that establishes lifelong infection in its host and can cause severe comorbidities in individuals with suppressed or compromised immune systems. The lifecycle of HCMV consists of lytic and latent phases, largely dependent upon the cell type infected and whether transcription from the major immediate early locus can ensue. Control of this locus, which acts as a critical "switch" region from where the lytic gene expression cascade originates, as well as regulation of the additional ~235 kilobases of virus genome, occurs through chromatinization with cellular histone proteins after infection. Upon infection of a host cell, an initial intrinsic antiviral response represses gene expression from the incoming genome, which is relieved in permissive cells by viral and host factors in concert. Latency is established in a subset of hematopoietic cells, during which viral transcription is largely repressed while the genome is maintained. As these latently infected cells differentiate, the cellular milieu and epigenetic modifications change, giving rise to the initial stages of virus reactivation from latency. Thus, throughout the cycle of infection, chromatinization, chromatin modifiers, and the recruitment of specific transcription factors influence the expression of genes from the HCMV genome. In this review, we discuss epigenetic regulation of the HCMV genome during the different phases of infection, with an emphasis on recent reports that add to our current perspective.
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Cromatina , Infecciones por Citomegalovirus , Humanos , Epigénesis Genética , Latencia del Virus/genética , Histonas/metabolismo , Citomegalovirus/fisiología , Regulación Viral de la Expresión GénicaRESUMEN
Vitamin K1 (VitK1) and Vitamin K2 (VitK2), two important naturally occurring micronutrients in the VitK family, found, respectively, in green leafy plants and algae (VitK1) and animal and fermented foods (VitK2). The present review explores the multiple biological functions of VitK2 from recently published in vitro and in vivo studies, including promotion of osteogenesis, prevention of calcification, relief of menopausal symptoms, enhancement of mitochondrial energy release, hepato- and neuro-protective effects, and possible use in treatment of coronavirus disease. The mechanisms of action associated with these biological effects are also explored. Overall, the findings presented here suggest that VitK, especially VitK2, is an important nutrient family for the normal functioning of human health. It acts on almost all major body systems and directly or indirectly participates in and regulates hundreds of physiological or pathological processes. However, as biological and clinical data are still inconsistent and conflicting, more in-depth investigations are warranted to elucidate its potential as a therapeutic strategy to prevent and treat a range of disease conditions.
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Interactions between tumor cells and the tumor microenvironment are critical for tumor growth, progression, and response to therapy. Effective targeting of oncogenic signaling pathways in tumors requires an understanding of how these therapies impact both tumor cells and cells within the tumor microenvironment. One such pathway is the janus kinase (JAK)/signal transducer and activator or transcription (STAT) pathway, which is activated in both breast cancer cells and in tumor associated macrophages. This study demonstrates that exposure of macrophages to JAK inhibitors leads to activation of NF-κB signaling, which results in increased expression of genes known to be associated with therapeutic resistance. Furthermore, inhibition of the NF-κB pathway improves the ability of ruxolitinib to reduce mammary tumor growth in vivo. Thus, the impact of the tumor microenvironment is an important consideration in studying breast cancer and understanding such mechanisms of resistance is critical to development of effective targeted therapies.
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Neoplasias de la Mama , Inhibidores de las Cinasas Janus , Humanos , Femenino , FN-kappa B/metabolismo , Inhibidores de las Cinasas Janus/farmacología , Inhibidores de las Cinasas Janus/uso terapéutico , Transducción de Señal , Quinasas Janus/metabolismo , Neoplasias de la Mama/tratamiento farmacológico , Factores de Transcripción STAT/metabolismo , Microambiente TumoralRESUMEN
The activation of thymic B cells is critical for their licensing as antigen presenting cells and resulting ability to mediate T cell central tolerance. The processes leading to licensing are still not fully understood. By comparing thymic B cells to activated Peyer's patch B cells at steady state, we found that thymic B cell activation starts during the neonatal period and is characterized by TCR/CD40-dependent activation, followed by immunoglobulin class switch recombination (CSR) without forming germinal centers. Transcriptional analysis also demonstrated a strong interferon signature, which was not apparent in the periphery. Thymic B cell activation and CSR were primarily dependent on type III IFN signaling, and loss of type III IFN receptor in thymic B cells resulted in reduced thymocyte regulatory T cell (Treg) development. Finally, from TCR deep sequencing, we estimate that licensed B cells induce development of a substantial fraction of the Treg cell repertoire. Together, these findings reveal the importance of steady-state type III IFN in generating licensed thymic B cells that induce T cell tolerance to activated B cells.