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Abstract Intracellular bacteria produce antigens, which serve as potent activators of γδ T cells. Phosphoantigens are presented via a complex of butyrophilins (BTN) to signal infection to human Vγ9+Vδ2+ T cells. Here, we established an in vitro system allowing for studies of Vγ9+Vδ2+ T cell activity in coculture with epithelial cells infected with the intracellular bacterial pathogen Listeria monocytogenes. We report that the Vγ9+Vδ2+ T cells efficiently control L. monocytogenes growth in such cultures. This effector function requires the expression of members of the BTN3A family on epithelial cells. Specifically, we observed a BTN3A1-independent BTN3A3 activity to present antigen to Vγ9+Vδ2+ T cells. Since BTN3A1 is the only BTN3A associated with phosphoantigen presentation, our study suggests that BTN3A3 may present different classes of antigens to mediate Vγ9+Vδ2+ T cell effector function against L. monocytogenes-infected epithelia.

Abstract Biomechanical cues are instrumental in guiding embryonic development and cell differentiation. Understanding how these physical stimuli translate into transcriptional programs will provide insight into mechanisms underlying mammalian pre-implantation development. Here, we explore this type of regulation by exerting microenvironmental control over mouse embryonic stem cells. Microfluidic encapsulation of mouse embryonic stem cells in agarose microgels stabilizes the naive pluripotency network and specifically induces expression of Plakoglobin (Jup), a vertebrate homolog of β-catenin. Overexpression of Plakoglobin is sufficient to fully re-establish the naive pluripotency gene regulatory network under metastable pluripotency conditions, as confirmed by single-cell transcriptome profiling. Finally, we find that, in the epiblast, Plakoglobin was exclusively expressed at the blastocyst stage in human and mouse embryos – further strengthening the link between Plakoglobin and naive pluripotency in vivo. Our work reveals Plakoglobin as a mechanosensitive regulator of naive pluripotency and provides a paradigm to interrogate the effects of volumetric confinement on cell-fate transitions.

Abstract Age-associated B cells (ABC) accumulate with age and in individuals with different immunological disorders, including cancer patients treated with immune checkpoint blockade and those with inborn errors of immunity. Here, we investigate whether ABCs from different conditions are similar and how they impact the longitudinal level of the COVID-19 vaccine response. Single-cell RNA sequencing indicates that ABCs with distinct aetiologies have common transcriptional profiles and can be categorised according to their expression of immune genes, such as the autoimmune regulator (AIRE). Furthermore, higher baseline ABC frequency correlates with decreased levels of antigen-specific memory B cells and reduced neutralising capacity against SARS-CoV-2. ABCs express high levels of the inhibitory FcγRIIB receptor and are distinctive in their ability to bind immune complexes, which could contribute to diminish vaccine responses either directly, or indirectly via enhanced clearance of immune complexed-antigen. Expansion of ABCs may, therefore, serve as a biomarker identifying individuals at risk of suboptimal responses to vaccination.

Here we report the application of a multi-disciplinary protocol for investigating thiazolidin-4-one-based compounds as new promising anti-inflammatory agents interfering with the eicosanoid biosynthesis pathways. The workflow foresaw the generation of a focused virtual library of ∼4.2 ​× ​104 molecules featuring the thiazolidin-4-one core based on the related one-pot synthetical combinatorial route. The built library was initially screened in silico against the microsomal prostaglandin E2 synthase-1 (mPGES-1) enzyme and, afterwards, 23 selected chemical items were synthesized for the subsequent biological screening, applying the one-pot multicomponent synthetic strategy. Preliminary results highlighted the moderate ability of several tested thiazolidin-4-one-based compounds in inhibiting mPGES-1. On the other hand, further computational repurposing investigations were performed on a set of synthesized compounds, highlighting the promising binding of a several items against the soluble epoxide hydrolase (sEH) enzyme, whose inhibition leads to an increase of epoxyeicosatrienoic acids (EETs) that are anti-inflammatory mediators. Three molecules (3, 9 and 21) were able to inhibit sEH featuring IC50 values in the low micromolar range. In order to further profile their anti-inflammatory properties, additional investigations of the three identified hits highlighted their ability to inhibit 5-lipoxygenase (5-LO) and thus to interfere with leukotriene biosynthesis in neutrophils, devoid of activity against cyclooxygenases (COXs) and cytotoxic effects on human monocytes. Our results, obtained by applying a multidisciplinary approach, highlight the thiazolidin-4-one-core as a valuable template for developing novel anti-inflammatory compounds able to synergistically inhibit different targets involved in the arachidonic acid cascade.

The soluble bioactive form of the transmembrane protein fibronectin type III domain containing 4 (sFNDC4) has anti-inflammatory effects and improves insulin sensitivity. Here the authors show that liver derived sFNDC4 signals through adipose tissue GPCR GPR116 to promote insulin-mediated glucose uptake.

Current methods to generate sequence-function data at large scale are either technically complex or limited to specific applications. Here the authors introduce DNA-based phenotypic recording to overcome these limitations and enable deep learning for accurate prediction of function from sequence.

Beta-adrenergic stimulation of brown adipose tissue leads to thermogenesis via the activating transcription factor 2 (ATF2) mediated expression of the thermogenic genes Ucp1 and Pgc-1α. Here, the authors show that the scaffold protein p62 regulates brown adipose tissue function through modifying ATF2 genomic binding and subsequent Ucp1 and Pgc-1α induction.

A rapid cellular response to interferons (IFNs) is critical for establishing antimicrobial immunity, but how cells switch from from homeostasis to IFN signaling is not fully understood. Here, the authors provide evidence that IFNs induce gene expression by alternating subunits of transcription factor ISGF3.

Abstract Background Expert psychiatrists conducting work disability evaluations often disagree on work capacity (WC) when assessing the same patient. More structured and standardised evaluations focusing on function could improve agreement. The RELY studies aimed to establish the inter-rater reproducibility (reliability and agreement) of ‘functional evaluations’ in patients with mental disorders applying for disability benefits and to compare the effect of limited versus intensive expert training on reproducibility. Methods We performed two multi-centre reproducibility studies on standardised functional WC evaluation (RELY 1 and 2). Trained psychiatrists interviewed 30 and 40 patients respectively and determined WC using the Instrument for Functional Assessment in Psychiatry (IFAP). Three psychiatrists per patient estimated WC from videotaped evaluations. We analysed reliability (intraclass correlation coefficients [ICC]) and agreement (‘standard error of measurement’ [SEM] and proportions of comparisons within prespecified limits) between expert evaluations of WC. Our primary outcome was WC in alternative work (WCalternative.work), 100–0%. Secondary outcomes were WC in last job (WClast.job), 100–0%; patients’ perceived fairness of the evaluation, 10–0, higher is better; usefulness to psychiatrists. Results Inter-rater reliability for WCalternative.work was fair in RELY 1 (ICC 0.43; 95%CI 0.22–0.60) and RELY 2 (ICC 0.44; 0.25–0.59). Agreement was low in both studies, the ‘standard error of measurement’ for WCalternative.work was 24.6 percentage points (20.9–28.4) and 19.4 (16.9–22.0) respectively. Using a ‘maximum acceptable difference’ of 25 percentage points WCalternative.work between two experts, 61.6% of comparisons in RELY 1, and 73.6% of comparisons in RELY 2 fell within these limits. Post-hoc secondary analysis for RELY 2 versus RELY 1 showed a significant change in SEMalternative.work (− 5.2 percentage points WCalternative.work [95%CI − 9.7 to − 0.6]), and in the proportions on the differences ≤ 25 percentage points WCalternative.work between two experts (p = 0.008). Patients perceived the functional evaluation as fair (RELY 1: mean 8.0; RELY 2: 9.4), psychiatrists as useful. Conclusions Evidence from non-randomised studies suggests that intensive training in functional evaluation may increase agreement on WC between experts, but fell short to reach stakeholders’ expectations. It did not alter reliability. Isolated efforts in training psychiatrists may not suffice to reach the expected level of agreement. A societal discussion about achievable goals and readiness to consider procedural changes in WC evaluations may deserve considerations.

Objective: The contribution of brown adipose tissue (BAT) to adult human metabolic control is a topic of ongoing investigation. In context, understanding the cellular events leading to BAT uncoupling, heat production, and energy expenditure is anticipated to produce significant insight into this endeavor. The phosphoinositide interacting regulator of transient receptor potentials (Pirt) was recently put forward as a key protein regulating cold sensing downstream of the transient receptor potential melastatin 8 (TRPM8). Notably, TRPM8 has been identified as a non-canonical regulator of BAT thermogenesis. The aim of this investigation was to delineate the role of Pirt in energy homeostasis and glucose metabolism - and the possible involvement of Pirt in TRPM8-elicited energy expenditure. Methods: To this end, we metabolically phenotyped male and female Pirt deficient (Pirt−/−) mice exposed to a low-fat chow diet or to a high-fat, high-sugar (HFHS) diet. Results: We identified that chow-fed female Pirt−/− mice have an increased susceptibility to develop obesity and glucose intolerance. This effect is abrogated when the mice are exposed to a HFHS diet. Conversely, Pirt−/− male mice display no metabolic phenotype on either diet relative to wild-type (WT) control mice. Finally, we observed that Pirt is dispensable for TRPM8-evoked energy expenditure. Conclusion: We here report subtle metabolic abnormalities in female, but not male, Pirt−/− mice. Future studies are required to tease out if metabolic stressors beyond dietary interventions, e.g. temperature fluctuations, are interacting with Pirt-signaling and metabolic control in a sex-specific fashion. Keywords: Signaling molecule, Sex differences, Body weight, Energy metabolism, TRPM8, Brown adipose tissue

The development of new bioactive compounds represents one of the main purposes of the drug discovery process. Various tools can be employed to identify new drug candidates against pharmacologically relevant biological targets, and the search for new approaches and methodologies often represents a critical issue. In this context, in silico drug repositioning procedures are required even more in order to re-evaluate compounds that already showed poor biological results against a specific biological target. 3D structure-based pharmacophoric models, usually built for specific targets to accelerate the identification of new promising compounds, can be employed for drug repositioning campaigns as well. In this work, an in-house library of 190 synthesized compounds was re-evaluated using a 3D structure-based pharmacophoric model developed on soluble epoxide hydrolase (sEH). Among the analyzed compounds, a small set of quinazolinedione-based molecules, originally selected from a virtual combinatorial library and showing poor results when preliminarily investigated against heat shock protein 90 (Hsp90), was successfully repositioned against sEH, accounting the related built 3D structure-based pharmacophoric model. The promising results here obtained highlight the reliability of this computational workflow for accelerating the drug discovery/repositioning processes.

We report the implementation of our in silico/synthesis pipeline by targeting the glutathione-dependent enzyme mPGES-1, a valuable macromolecular target in both cancer therapy and inflammation therapy. Specifically, by using a virtual fragment screening approach of aromatic bromides, straightforwardly modifiable by the Suzuki-Miyaura reaction, we identified 3-phenylpropanoic acid and 2-(thiophen-2-yl)acetic acid to be suitable chemical platforms to develop tighter mPGES-1 inhibitors. Among these, compounds 1c and 2c showed selective inhibitory activity against mPGES-1 in the low micromolar range in accordance with molecular modeling calculations. Moreover, 1c and 2c exhibited interesting IC50 values on A549 cell lines compared to CAY10526, selected as reference compound. The most promising compound 2c induced the cycle arrest in the G0/G1 phase at 24 h of exposure, whereas at 48 and 72 h, it caused an increase of subG0/G1 fraction, suggesting an apoptosis/necrosis effect.

Cutibacterium (previously Propionibacterium) acnes is an anaerobic, Gram-positive commensal of the human body. The bacterium has been associated with a variety of diseases, including acne vulgaris, prosthetic joint infections, prostate cancer, and sarcoidosis. The accumulation of C. acnes in diseases such as acne and prostate cancer has been shown to correlate with enhanced inflammation. While the C. acnes-induced proinflammatory axis, via NF-κB and MAPK signaling and inflammasome activation, has been investigated over the last few decades, the potential role of C. acnes in triggering the type I interferon (IFN-I) pathway has not been addressed. Our results show that C. acnes induces the IFN-I signaling axis in human macrophages by triggering the cGAS-STING pathway. In addition, IFN-I signaling induced by C. acnes strongly depends on the adapter protein TRIF in a non-canonical manner; these signaling events occurred in the absence of any detectable intracellular replication of the bacterium. Collectively, our results provide important insight into C. acnes-induced intracellular signaling cascades in human macrophages and suggest IFN-I as a factor in the etiology of C. acnes-induced diseases. This knowledge may be valuable for developing novel therapies targeting C. acnes in diseases where the accumulation of the bacterium leads to an inflammatory pathology.

BackgroundThere are currently no tools for assessing claimants' perceived fairness in work disability evaluations. In our study, we describe the development and validation of a questionnaire for this purpose.MethodIn cooperation with subject-matter experts of Swiss insurance medicine, we developed the 30-item Basel Fairness Questionnaire (BFQ). Claimants anonymously answered the questionnaire immediately after their disability evaluation, still unaware about its outcome. For each item, there were four response options, ranging from "strongly disagree" to "strongly agree". The construct validity of the BFQ was assessed by running a principal component analysis (PCA).ResultsIn 4% of the questionnaires, the claimants' perception on the disability evaluation was negative (below the median of the scale). The PCA of the items responses followed by an orthogonal rotation revealed four factors, namely (1) Interviewing Skills, (2) Rapport, (3) Transparency, and (4) Case Familiarity, explaining 63.5% of the total variance.DiscussionThe ratings presumably have some positive bias by sample selection and response bias. The PCA factors corresponded to dimensions that subject-matter experts had beforehand identified as relevant. However, all item ratings were highly intercorrelated, which suggests that the presumed underlying dimensions are not independent.ConclusionThe BFQ represents the first self-administered instrument for measuring claimants' perceived fairness of work disability evaluations, allowing the assessment of informational, procedural, and interactive justice from the perspective of claimants. In cooperation with Swiss assessment centres, we plan to implement a refined version of the BFQ as feedback instrument in work disability evaluations.

Tanshinone IIA (TIIA) and cryptotanshinone (CRY) from Salvia miltiorrhiza Bunge were investigated for their inhibitory activity against the cyclooxygenase-2 (COX-2)/microsomal prostaglandin E synthase-1 (mPGES-1)/endothelial prostaglandin 3 (EP3) pathway using in silico, in vitro, in vivo, and ex vivo assays. From the analysis of the docking poses, both diterpenoids were able to interact significantly with COX-2, 5-lipoxygenase (5-LO), platelet-activating factor receptor (PAFR), and mPGES-1. This evidence was further corroborated by data obtained from a cell-free assay, where CRY displayed a significant inhibitory potency against mPGES-1 (IC50 = 1.9 ± 0.4 µM) and 5-LO (IC50 = 7.1 µM), while TIIA showed no relevant inhibition of these targets. This was consistent with their activity to increase mice bleeding time (CRY: 2.44 ± 0.13 min, p ≤ 0.001; TIIA: 2.07 ± 0.17 min p ≤ 0.01) and with the capability to modulate mouse clot retraction (CRY: 0.048 ± 0.011 g, p ≤ 0.01; TIIA: 0.068 ± 0.009 g, p ≤ 0.05). For the first time, our results show that TIIA and, in particular, CRY are able to interact significantly with the key proteins involved not only in the onset of inflammation but also in platelet activity (and hyper-reactivity). Future preclinical and clinical investigations, together with this evidence, could provide the scientific basis to consider these compounds as an alternative therapeutic approach for thrombotic- and thromboembolic-based diseases.

Tobacco smoking and cold exposure are environmental modulators of human energy metabolism suppressing appetite and increasing energy expenditure, respectively. Here, the authors develop a novel pharmacological strategy in which they simultaneously mimic the metabolic benefits of both phenomena through small-molecule combination therapy, and show that this treatment improves metabolic health of obese mice.

DExD/H box RNA helicases, such as the RIG-I-like receptors (RLR), are important components of the innate immune system. Here we demonstrate a pivotal and sex-specific role for the heterosomal isoforms of the DEAD box RNA helicase DDX3 in the immune system. Mice lacking DDX3X during hematopoiesis showed an altered leukocyte composition in bone marrow and spleen and a striking inability to combat infection with Listeria monocytogenes. Alterations in innate immune responses resulted from decreased effector cell availability and function as well as a sex-dependent impairment of cytokine synthesis. Thus, our data provide further in vivo evidence for an essential contribution of a non-RLR DExD/H RNA helicase to innate immunity and suggest it may contribute to sex-related differences in resistance to microbes and resilience to inflammatory disease.

Circadian clocks are fundamental physiological regulators of energy homeostasis, but direct transcriptional targets of the muscle clock machinery are unknown. To understand how the muscle clock directs rhythmic metabolism, we determined genome-wide binding of the master clock regulators brain and muscle ARNT-like protein 1 (BMAL1) and REV-ERBα in murine muscles. Integrating occupancy with 24-hr gene expression and metabolomics after muscle-specific loss of BMAL1 and REV-ERBα, here we unravel novel molecular mechanisms connecting muscle clock function to daily cycles of lipid and protein metabolism. Validating BMAL1 and REV-ERBα targets using luciferase assays and in vivo rescue, we demonstrate how a major role of the muscle clock is to promote diurnal cycles of neutral lipid storage while coordinately inhibiting lipid and protein catabolism prior to awakening. This occurs by BMAL1-dependent activation of Dgat2 and REV-ERBα-dependent repression of major targets involved in lipid metabolism and protein turnover (MuRF-1, Atrogin-1). Accordingly, muscle-specific loss of BMAL1 is associated with metabolic inefficiency, impaired muscle triglyceride biosynthesis, and accumulation of bioactive lipids and amino acids. Taken together, our data provide a comprehensive overview of how genomic binding of BMAL1 and REV-ERBα is related to temporal changes in gene expression and metabolite fluctuations.

CRISPR interference (CRISPRi) using dCas9-sgRNA is a powerful tool for the exploration and manipulation of gene functions. Here we quantify the reversible switching of a central process of the bacterial cell cycle by CRISPRi and an antisense RNA mechanism. Reversible induction of filamentous growth in E. coli has been recently demonstrated by controlling the expression levels of the bacterial cell division proteins FtsZ/FtsA via CRISPRi. If FtsZ falls below a critical level, cells cannot divide. However, the cells remain metabolically active and continue with DNA replication. We surmised that this makes them amenable to an inducible antisense RNA strategy to counteract FtsZ inhibition. We show that both static and inducible thresholds can adjust the characteristics of the switching process. Combining bulk data with single cell measurements, we characterize the efficiency of the switching process. Successful restoration of division is found to occur faster in the presence of antisense sgRNAs than upon simple termination of CRISPRi induction.

Abstract We assessed the efficacy of simultaneous agonism at the glucagon‐like peptide‐1 receptor (GLP‐1R) and the melanocortin‐4 receptor (MC4R) for the treatment of obesity and diabetes in rodents. Diet‐induced obese (DIO) mice were chronically treated with either the long‐acting GLP‐1R agonist liraglutide, the MC4R agonist RM‐493 or a combination of RM‐493 and liraglutide. Co‐treatment of DIO mice with RM‐493 and liraglutide improves body weight loss and enhances glycemic control and cholesterol metabolism beyond what can be achieved with either mono‐therapy. The superior metabolic efficacy of this combination therapy is attributed to the anorectic and glycemic actions of both drugs, along with the ability of RM‐493 to increase energy expenditure. Interestingly, compared to mice treated with liraglutide alone, hypothalamic Glp‐1r expression was higher in mice treated with the combination therapy after both acute and chronic treatment. Further, RM‐493 enhanced hypothalamic Mc4r expression. Hence, co‐dosing with MC4R and GLP‐1R agonists increases expression of each receptor, indicative of minimized receptor desensitization. Together, these findings suggest potential opportunities for employing combination treatments that comprise parallel MC4R and GLP‐1R agonism for the treatment of obesity and diabetes.

Nitrate reductase (NR) is important for higher land plants, as it catalyzes the rate-limiting step in the nitrate assimilation pathway, the two-electron reduction of nitrate to nitrite. Furthermore, it is considered to be a major enzymatic source of the important signaling molecule nitric oxide (NO), that is produced in a one-electron reduction of nitrite. Like many other plants, the model plant Arabidopsis thaliana expresses two isoforms of NR (NIA1 and NIA2). Up to now, only NIA2 has been the focus of detailed biochemical studies, while NIA1 awaits biochemical characterization. In this study, we have expressed and purified functional fragments of NIA1 and subjected them to various biochemical assays for comparison with the corresponding NIA2-fragments. We analyzed the kinetic parameters in multiple steady-state assays using nitrate or nitrite as substrate and measured either substrate consumption (nitrate or nitrite) or product formation (NO). Our results show that NIA1 is the more efficient nitrite reductase while NIA2 exhibits higher nitrate reductase activity, which supports the hypothesis that the isoforms have special functions in the plant. Furthermore, we successfully restored the physiological electron transfer pathway of NR using reduced nicotinamide adenine dinucleotide (NADH) and nitrate or nitrite as substrates by mixing the N-and C-terminal fragments of NR, thus, opening up new possibilities to study NR activity, regulation and structure.

In the original PDF version of this article, affiliation 1, ‘Institute for Diabetes and Obesity, Helmholtz Diabetes Center (HDC), Helmholtz Zentrum Muenchen & German Center for Diabetes Research (DZD), Neuherberg, Germany’, was incorrectly given as ‘Institute of Diabetes and Regeneration Research, Helmholtz Zentrum Muenchen, German Research Center for Environmental Health (GmbH), Neuherberg, Germany ‘. This has now been corrected in the PDF version of the article; the HTML version was correct at the time of publication.

QUESTIONS: In Switzerland, evaluation of work capacity in individuals with mental disorders has come under criticism. We surveyed stakeholders about their concerns and expectations of the current claim process. METHODS: We conducted a nationwide online survey among five stakeholder groups. We asked 37 questions addressing the claim process and the evaluation of work capacity, the maximum acceptable disagreement in judgments on work capacity, and its documentation. RESULTS: Response rate among 704 stakeholders (95 plaintiff lawyers, 285 treating psychiatrists, 129 expert psychiatrists evaluating work capacity, 64 social judges, 131 insurers) varied between 71% and 29%. Of the lawyers, 92% were dissatisfied with the current claim process, as were psychiatrists (73%) and experts (64%), whereas the majority of judges (72%) and insurers (81%) were satisfied. Stakeholders agreed in their concerns, such as the lack of a transparent relationship between the experts’ findings and their conclusions regarding work capacity, medical evaluations inappropriately addressing legal issues, and the experts’ delay in finalising the report. Findings mirror the characteristics that stakeholders consider important for an optimal work capacity evaluation. For a scenario where two experts evaluate the same claimant, stakeholders considered an inter-rater difference of 10%‒20% in work capacity at maximum acceptable. CONCLUSIONS: Plaintiff lawyers, treating psychiatrists and experts perceive major problems in work capacity evaluation of psychiatric claims whereas judges and insurers see the process more positively. Efforts to improve the process should include clarifying the basis on which judgments are made, restricting judgments to areas of expertise, and ensuring prompt submission of evaluations.

Genetic recombination between pathogens derived from humans and livestock has the potential to create novel pathogen strains, highlighted by the influenza pandemic H1N1/09, which was derived from a re-assortment of swine, avian and human influenza A viruses. Here we investigated whether genetic recombination between subspecies of the protozoan parasite, Trypanosoma brucei, from humans and animals can generate new strains of human pathogen, T. b. rhodesiense (Tbr) responsible for sleeping sickness (Human African Trypanosomiasis, HAT) in East Africa. The trait of human infectivity in Tbr is conferred by a single gene, SRA, which is potentially transferable to the animal pathogen Tbb by sexual reproduction. We tracked the inheritance of SRA in crosses of Tbr and Tbb set up by co-transmitting genetically-engineered fluorescent parental trypanosome lines through tsetse flies. SRA was readily transferred into new genetic backgrounds by sexual reproduction between Tbr and Tbb, thus creating new strains of the human pathogen, Tbr. There was no evidence of diminished growth or transmissibility of hybrid trypanosomes carrying SRA. Although expression of SRA is critical to survival of Tbr in the human host, we show that the gene exists as a single copy in a representative collection of Tbr strains. SRA was found on one homologue of chromosome IV in the majority of Tbr isolates examined, but some Ugandan Tbr had SRA on both homologues. The mobility of SRA by genetic recombination readily explains the observed genetic variability of Tbr in East Africa. We conclude that new strains of the human pathogen Tbr are being generated continuously by recombination with the much larger pool of animal-infective trypanosomes. Such novel recombinants present a risk for future outbreaks of HAT.

Molybdenum and tungsten cofactors share a similar pterin-based scaffold, which hosts an ene-dithiolate function being essential for the coordination of either molybdenum or tungsten. The biosynthesis of both cofactors involves a multistep pathway, which ends with the activation of the metal binding pterin (MPT) by adenylylation before the respective metal is incorporated. In the hyperthermophilic organism Pyrococcus furiosus, the hexameric protein MoaB (PfuMoaB) has been shown to catalyse MPT-adenylylation. Here we determined the crystal structure of PfuMoaB at 2.5 Å resolution and identified key residues of α3-helix mediating hexamer formation. Given that PfuMoaB homologues from mesophilic organisms form trimers, we investigated the impact on PfuMoaB hexamerization on thermal stability and activity. Using structure-guided mutagenesis, we successfully disrupted the hexamer interface in PfuMoaB. The resulting PfuMoaB-H3 variant formed monomers, dimers and trimers as determined by size exclusion chromatography. Circular dichroism spectroscopy as well as chemical cross-linking coupled to mass spectrometry confirmed a wild-type-like fold of the protomers as well as inter-subunits contacts. The melting temperature of PfuMoaB-H3 was found to be reduced by more than 15 °C as determined by differential scanning calorimetry, thus demonstrating hexamerization as key determinant for PfuMoaB thermal stability. Remarkably, while a loss of activity at temperatures higher than 50 °C was observed in the PfuMoaB-H3 variant, at lower temperatures, we determined a significantly increased catalytic activity. The latter suggests a gain in conformational flexibility caused by the disruption of the hexamerization interface.

QUESTIONS UNDER STUDY: In Switzerland, psychiatric evaluations of work capacity for determining a person’s eligibility for disability benefits are being criticised for a lack of transparency and high inter-rater variability. The aims of this study were to learn about the current practice of psychiatrists, to explore possible sources for lack of transparency and variability, and to contrast practice with current professional guidance. METHODS: A national online-survey among psychiatrists who performed five or more evaluations of work capacity per year. Based on discussions with experts and a literature review, we structured questions focusing on reporting on work capacity, the description of a claimant’s previous job, and measures of quality assurance. RESULTS: A total of 129 psychiatrists responded (31% of estimated 412 eligible psychiatrists). The majority reported using instructions of the insurers (77%), peer consulting (65%) and process guidelines (51%). They expressed a claimant’s work capacity as free text and percentage work capacity (49%), percentage only (23%), or free text only (14%). A total of 13% used instruments to document work capacity. Psychiatrists considered three different interpretations of percentage work capacity as equally applicable. A job description was regarded as mandatory to determine work capacity by 90% but only 26% received it and found it mostly deficient. CONCLUSIONS: The transparency and reliability of Swiss psychiatrists’ conclusions on a claimant's work capacity may be reduced by unsystematic reporting, variable interpretation of the percentage work capacity, lack of a detailed job description and insufficient quality control. Education, engagement of insurers and new guidelines might be effective means of implementing improvements.

Human endogenous retrovirus (HERV) genomes are chromosomally integrated in all cells of an individual. They are normally transcriptionally silenced and transmitted only vertically. Enhanced expression of HERV-K accompanied by the emergence of anti-HERV-K-directed immune responses has been observed in tumor patients and HIV-infected individuals. As HERV-K is usually not expressed and immunological tolerance development is unlikely, it is an appropriate target for the development of immunotherapies. We generated a recombinant vaccinia virus (MVA-HKenv) expressing the HERV-K envelope glycoprotein (ENV), based on the modified vaccinia virus Ankara (MVA), and established an animal model to test its vaccination efficacy. Murine renal carcinoma cells (Renca) were genetically altered to express E. coli beta-galactosidase (RLZ cells) or the HERV-K ENV gene (RLZ-HKenv cells). Intravenous injection of RLZ-HKenv cells into syngenic BALB/c mice led to the formation of pulmonary metastases, which were detectable by X-gal staining. A single vaccination of tumor-bearing mice with MVA-HKenv drastically reduced the number of pulmonary RLZ-HKenv tumor nodules compared to vaccination with wild-type MVA. Prophylactic vaccination of mice with MVA-HKenv precluded the formation of RLZ-HKenv tumor nodules, whereas wild-type MVA-vaccinated animals succumbed to metastasis. Protection from tumor formation correlated with enhanced HERV-K ENV-specific killing activity of splenocytes. These data demonstrate for the first time that HERV-K ENV is a useful target for vaccine development and might offer new treatment opportunities for diverse types of cancer.