FcγRIIA-specific DARPins as novel tools in blood cell analysis and platelet aggregation.

Fc receptors are involved in a variety of physiologically and disease-relevant responses. Among them, FcγRIIA (CD32a) is known for its activating functions in pathogen recognition and platelet biology, and, as potential marker of T lymphocytes latently infected with HIV-1. The latter has not been without controversy due to technical challenges complicated by T-B cell conjugates and trogocytosis as well as a lack of antibodies distinguishing between the closely related isoforms of FcγRII. To generate high-affinity binders specific for FcγRIIA, libraries of designed ankyrin repeat proteins (DARPins) were screened for binding to its extracellular domains by ribosomal display. Counterselection against FcγRIIB eliminated binders cross-reacting with both isoforms. The identified DARPins bound FcγRIIA with no detectable binding for FcγRIIB. Their affinities for FcγRIIA were in the low nanomolar range and could be enhanced by cleavage of the His-tag and dimerization. Interestingly, complex formation between DARPin and FcγRIIA followed a two-state reaction model, and discrimination from FcγRIIB was based on a single amino acid residue. In flow cytometry, DARPin F11 detected FcγRIIA+ cells even when they made up less than 1% of the cell population. Image stream analysis of primary human blood cells confirmed that F11 caused dim but reliable cell surface staining of a small subpopulation of T lymphocytes. When incubated with platelets, F11 inhibited their aggregation equally efficient as antibodies unable to discriminate between both FcγRII isoforms. The selected DARPins are unique novel tools for platelet aggregation studies as well as the role of FcγRIIA for the latent HIV-1 reservoir.

The temporal association between social isolation, distress, and psychotic experiences in individuals at clinical high-risk for psychosis.

BACKGROUND: Psychotic experiences (PEs) and social isolation (SI) seem related during early stages of psychosis, but the temporal dynamics between the two are not clear. Literature so far suggests a self-perpetuating cycle wherein momentary increases in PEs lead to social withdrawal, which, subsequently, triggers PEs at a next point in time, especially when SI is associated with increased distress. The current study investigated the daily-life temporal associations between SI and PEs, as well as the role of SI-related and general affective distress in individuals at clinical high risk (CHR) for psychosis. METHODS: We used experience sampling methodology in a sample of 137 CHR participants. We analyzed the association between SI, PEs, and distress using time-lagged linear mixed-effects models. RESULTS: SI did not predict next-moment fluctuations in PEs, or vice versa. Furthermore, although SI-related distress was not predictive of subsequent PEs, general affective distress during SI was a robust predictor of next-moment PEs. CONCLUSIONS: Our results suggest that SI and PEs are not directly related on a moment-to-moment level, but a negative emotional state when alone does contribute to the risk of PEs. These findings highlight the role of affective wellbeing during early-stage psychosis development.

Magic cluster sizes of cationic and anionic sodium chloride clusters explained by statistical modeling of the complete phase space.

As one of the main components of sea salt aerosols, sodium chloride is involved in numerous atmospheric processes. Gas-phase clusters are ideal models to study fundamental physical and chemical properties of sodium chloride, which are significantly affected by the cluster size. Of particular interest are magic cluster sizes, which exhibit high intensities in mass spectra. In order to understand the origin of these magic cluster sizes, quantum chemical calculations at the CCSD(T)//DFT level are performed, yielding structures and binding energies of neutral (NaCl)x, anionic (NaCl)xCl- and cationic (NaCl)xNa+ clusters up to x = 8. Our calculations show that the clusters can easily isomerize, enabling dissociation into the lowest-energy isomers of the fragments. Energetics can explain the special stability of (NaCl)4Cl-, but (NaCl)4Na+ actually offers low-lying dissociation channels, despite being a magic cluster size. Collision-induced dissociation experiments reveal that the loss of neutral clusters (NaCl)x, x = 2, 4, is in most cases more favorable than the loss of NaCl or the atomic ion, i.e. sodium chloride clusters actually fragment via the cleavage of the entire cluster, not by evaporating small cluster building blocks. This is rationalized by the calculated high stability of even-numbered neutral clusters (NaCl)x, especially x = 2, 4. Analysis of the density of states and rate constants calculated with a modified Rice-Ramsperger-Kassel-Marcus (RRKM) equation called AWATAR - considering all energetically accessible isomers of reactants and fragments - shows that entropic effects are responsible for the magic cluster character of (NaCl)4Na+. In particular, low-lying vibrational modes provide a high density of states of the near-planar cluster. Together with the small contribution of an atomic ion to the sum of states in a loose transition state for dissociation, this leads to a very small unimolecular rate constant for dissociation into (NaCl)4 and Na+, which is the lowest energy fragmentation pathway. Thus, entropic effects may override energetics for certain magic cluster sizes.

[Public mental health from an international perspective: from "shifting the curve" to inclusion of vulnerable populations]. / Public Mental Health in internationaler Perspektive: vom Shifting the Curve zur Inklusion vulnerabler Populationen.

In recent years, efforts in the field of public mental health have increased that seek to promote mental health and mental health literacy at population level and yield advances in the prevention, treatment and care of mental health conditions. This paper provides an overview of contemporary conceptualisations of indicators and determinants of public mental health as well as population-based intervention strategies from an international perspective. Current conceptual and methodological challenges of so-called high-risk, whole-population and vulnerable population strategies are critically discussed. Future efforts in research, policy and practice need to address fundamental causes of social and health inequalities, drawing on all societal fields, to contribute to improving population mental health.

Subjective and objective sleep in young people with borderline personality disorder features.

Characterising sleep in young people (aged 15-25 years) with borderline personality disorder (BPD) features is crucial given the association between BPD features and sleep disturbance, negative consequences of poor sleep, and normative developmental sleep changes that occur in this age group. The present study aimed to characterise the sleep profile of young people with BPD to determine whether this profile is non-normative and specific to BPD. Participants were 96 young people (40 with BPD features, 38 healthy individuals, and 18 young people seeking help for mental health difficulties without BPD). Sleep was measured subjectively (self-report questionnaires) and objectively (10 days of actigraphy). Young people with BPD features reported poorer subjective sleep quality, greater insomnia symptoms and later chronotype than same-age healthy and clinical comparison groups. Young people with BPD features also displayed irregular sleep timing, later rise times, greater time in bed and longer sleep durations than healthy young people. Those with BPD features had superior sleep quality (greater sleep efficiency, less wake after sleep onset) and longer sleep durations than the clinical comparison group. Sleep profiles were similar across young people with BPD features with and without co-occurring depression. Overall, the findings revealed a subjective-objective sleep discrepancy and suggest that sleep-improvement interventions might be beneficial to improve subjective sleep in young people with BPD features.

Size-dependent H and H2 formation by infrared multiple photon dissociation spectroscopy of hydrated vanadium cations, V+(H2O)n, n = 3-51.

Infrared spectra of the hydrated vanadium cation (V+(H2O)n; n = 3-51) were measured in the O-H stretching region employing infrared multiple photon dissociation (IRMPD) spectroscopy. Spectral fingerprints, along with size-dependent fragmentation channels, were observed and rationalized by comparing to spectra simulated using density functional theory. Photodissociation leading to water loss was found for cluster sizes n = 3-7, consistent with isomers featuring intact water ligands. Loss of molecular hydrogen was observed as a weak channel starting at n = 8, indicating the advent of inserted isomers, HVOH+(H2O)n-1. The majority of ions for n = 8, however, are composed of two-dimensional intact isomers, concordant with previous infrared studies on hydrated vanadium. A third channel, loss of atomic hydrogen, is observed weakly for n = 9-11, coinciding with the point at which the H and H2O calculated binding energies become energetically competitive for intact isomers. A clear and sudden spectral pattern and fragmentation channel intensity at n = 12 suggest a structural change to inserted isomers. The H2 channel intensity decreases sharply and is not observed for n = 20 and 25-51. IRMPD spectra for clusters sizes n = 15-51 are qualitatively similar indicating no significant structural changes, and are thought to be composed of inserted isomers, consistent with recent electronic spectroscopy experiments.

Comparing GENEActiv against Actiwatch-2 over Seven Nights Using a Common Sleep Scoring Algorithm and Device-Specific Wake Thresholds.

Demonstrating inter-device reliability is essential to use devices interchangeably, and accurately integrate, interpret, or compare data from different actigraphs. Despite this, there is a paucity of comparative literature over a timeframe exceeding one night. The aims of this study were to determine an optimal wake threshold for GENEActiv and to evaluate the concordance between Actiwatch-2 and GENEActiv using a common algorithm (Phillips Respironics). Data were collected from 33 individuals (20 female) aged 20-35 years (M= 25.33, SD = 4.69) across a total 213 nights. Participants wore both devices simultaneously and continuously for seven days. The sleep parameters of interest were: total sleep time, sleep efficiency, sleep onset latency, and wake after sleep onset. Exploratory analyses of sensitivity, specificity, overall accuracy, mean bias, and paired samples t-tests indicated an optimal wake threshold of 115 for GENEActiv, compared with Actiwatch-2 at the 40 (medium, default) threshold. Using these thresholds, sensitivity, and overall accuracy of GENEActiv were both good (86% and 78%, respectively), however specificity was relatively low (40%). There were no significant inter-device differences for any sleep parameters, and all absolute mean biases were small. Overall, the findings from this study provide the first empirical evidence to support the reliability of GENEActiv against Actiwatch-2 over multiple nights using a common algorithm with device-specific wake thresholds.

Current status and perspective of CAR-T and CAR-NK cell therapy trials in Germany.

Chimeric antigen receptor (CAR)-T cell therapies are on the verge of becoming powerful immunotherapeutic tools for combating hematological diseases confronted with pressing medical needs. Lately, CAR-NK cell therapies have also come into focus as novel therapeutic options to address hurdles related to CAR-T cell therapies, such as therapy-induced side effects. Currently, more than 500 CAR-T and 17 CAR-NK cell trials are being conducted worldwide including the four CAR-T cell products Kymriah, Yescarta, Tecartus and Breyanzi, which are already available on the market. Most CAR-T cell-based gene therapy products that are under clinical evaluation consist of autologous enriched T cells, whereas CAR-NK cell-based approaches can be generated from allogeneic donors. Besides modification based on a second-generation CAR, more advanced CAR-immune cell therapeutics are being tested, which utilize precise insertion of genes to circumvent graft-versus-host disease (GvHD) or employ a dual targeting approach and adapter CARs in order to avoid therapy resistance caused by antigen loss. In this review, we are going to take a closer look at the commercial CAR-T cell therapies, as well as on CAR-T and CAR-NK cell products, which are currently under evaluation in clinical trials, that are being conducted in Germany.

The association between migrant status and transition in an ultra-high risk for psychosis population.

PURPOSE: Migrant status is one of the most replicated and robust risk factors for developing a psychotic disorder. This study aimed to determine whether migrant status in people identified as Ultra-High Risk for Psychosis (UHR) was associated with risk of transitioning to a full-threshold psychotic disorder. METHODS: Hazard ratios for the risk of transition were calculated from five large UHR cohorts (n = 2166) and were used to conduct a meta-analysis using the generic inverse-variance method using a random-effects model. RESULTS: 2166 UHR young people, with a mean age of 19.1 years (SD ± 4.5) were included, of whom 221 (10.7%) were first-generation migrants. A total of 357 young people transitioned to psychosis over a median follow-up time of 417 days (I.Q.R.147-756 days), representing 17.0% of the cohort. The risk of transition to a full-threshold disorder was not increased for first-generation migrants, (HR = 1.08, 95% CI 0.62-1.89); however, there was a high level of heterogeneity between studies The hazard ratio for second-generation migrants to transition to a full-threshold psychotic disorder compared to the remainder of the native-born population was 1.03 (95% CI 0.70-1.51). CONCLUSIONS: This meta-analysis did not find a statistically significant association between migrant status and an increased risk for transition to a full-threshold psychotic disorder; however, several methodological issues could explain this finding. Further research should focus on examining the risk of specific migrant groups and also ensuring that migrant populations are adequately represented within UHR clinics.

Designed Ankyrin Repeat Protein (DARPin) to target chimeric antigen receptor (CAR)-redirected T cells towards CD4+ T cells to reduce the latent HIV+ cell reservoir.

Chimeric Antigen Receptor (CAR)-redirected T cells show great efficacy in the patient-specific therapy of hematologic malignancies. Here, we demonstrate that a DARPin with specificity for CD4 specifically redirects and triggers the activation of CAR engineered T cells resulting in the depletion of CD4+ target cells aiming for elimination of the human immunodeficiency virus (HIV) reservoir.

[Chimeric antigen receptors in oncology: clinical applications and new developments]. / Chimäre Antigenrezeptoren (CARs) in der Onkologie: eine Übersicht zu klinischer Anwendung und neuen Entwicklungen.

In 2018, two novel cancer therapies based on chimeric antigen receptors (CARs) were granted marketing authorization in the European Union. Authorized for use against advanced lymphoma and/or leukemia, the products were at the center of international attention, not only due to their novel mode of action and their encouraging efficacy but also because of their sometimes severe side effects and the economic and logistic challenges posed by their manufacture. Now, almost two years later, hundreds of active clinical trials emphasize the global drive to harness the full potential of CAR technology.In this article, we describe the mode of action of CAR T and CAR NK cells and review the clinical testing situation as well as early real-world data. In recent years, preclinical studies using advanced animal models have provided first insights into the mechanisms underlying the severe side effects of CAR T therapy. We summarize their results and describe the available models. Additionally, we discuss potential solutions to the hurdles currently limiting CAR technology. So far used as last-line treatment for patients with aggressive disease, CAR technology has the potential to become a new, broadly effective standard for tumor therapy.

At-risk studies and clinical antecedents of psychosis, bipolar disorder and depression: a scoping review in the context of clinical staging.

Identifying young people at risk of developing serious mental illness and identifying predictors of onset of illness has been a focus of psychiatric prediction research, particularly in the field of psychosis. Work in this area has facilitated the adoption of the clinical staging model of early clinical phenotypes, ranging from at-risk mental states to chronic and severe mental illness. It has been a topic of debate if these staging models should be conceptualised as disorder-specific or transdiagnostic. In order to inform this debate and facilitate cross-diagnostic discourse, the present scoping review provides a broad overview of the body of literature of (a) longitudinal at-risk approaches and (b) identified antecedents of (homotypic) illness progression across three major mental disorders [psychosis, bipolar disorder (BD) and depression], and places these in the context of clinical staging. Stage 0 at-risk conceptualisations (i.e. familial high-risk approaches) were identified in all three disorders. However, formalised stage 1b conceptualisations (i.e. ultra-high-risk approaches) were only present in psychosis and marginally in BD. The presence of non-specific and overlapping antecedents in the three disorders may support a general staging model, at least in the early stages of severe psychotic or mood disorders.

Receptor-Targeted Nipah Virus Glycoproteins Improve Cell-Type Selective Gene Delivery and Reveal a Preference for Membrane-Proximal Cell Attachment.

Receptor-targeted lentiviral vectors (LVs) can be an effective tool for selective transfer of genes into distinct cell types of choice. Moreover, they can be used to determine the molecular properties that cell surface proteins must fulfill to act as receptors for viral glycoproteins. Here we show that LVs pseudotyped with receptor-targeted Nipah virus (NiV) glycoproteins effectively enter into cells when they use cell surface proteins as receptors that bring them closely enough to the cell membrane (less than 100 Å distance). Then, they were flexible in receptor usage as demonstrated by successful targeting of EpCAM, CD20, and CD8, and as selective as LVs pseudotyped with receptor-targeted measles virus (MV) glycoproteins, the current standard for cell-type specific gene delivery. Remarkably, NiV-LVs could be produced at up to two orders of magnitude higher titers compared to their MV-based counterparts and were at least 10,000-fold less effectively neutralized than MV glycoprotein pseudotyped LVs by pooled human intravenous immunoglobulin. An important finding for NiV-LVs targeted to Her2/neu was an about 100-fold higher gene transfer activity when particles were targeted to membrane-proximal regions as compared to particles binding to a more membrane-distal epitope. Likewise, the low gene transfer activity mediated by NiV-LV particles bound to the membrane distal domains of CD117 or the glutamate receptor subunit 4 (GluA4) was substantially enhanced by reducing receptor size to below 100 Å. Overall, the data suggest that the NiV glycoproteins are optimally suited for cell-type specific gene delivery with LVs and, in addition, for the first time define which parts of a cell surface protein should be targeted to achieve optimal gene transfer rates with receptor-targeted LVs.

Detail, dynamics and depth: useful correctives for some current research trends.

Several research trends in contemporary psychiatry would benefit from greater emphasis on detailed assessment, modelling dynamic change, and micro-level analysis. This may assist with clarifying nosological and pathoaetiological issues. We make this case by referring to three areas: psychopathology and nosology; prediction research; and 'big N' data sets.Declaration of interestNone.

The Stalk Domain of NKp30 Contributes to Ligand Binding and Signaling of a Preassembled NKp30-CD3ζ Complex.

The natural cytotoxicity receptor (NCR) NKp30 (CD337) is a key player for NK cell immunosurveillance of infections and cancer. The molecular details of ligand recognition and its connection to CD3ζ signaling remain unsolved. Here, we show that the stalk domain (129KEHPQLGAGTVLLLR143) of NKp30 is very sensitive to sequence alterations, as mutations lead to impaired ligand binding and/or signaling capacity. Surprisingly, the stalk domains of NKp30 and NKp46, another NCR employing CD3ζ for signaling, were not exchangeable without drastic deficiencies in folding, plasma membrane targeting, and/or ligand-induced receptor signaling. Further mutational studies, N-glycosylation mapping, and plasma membrane targeting studies in the absence and presence of CD3ζ suggest two interconvertible types of NCR-CD3ζ assemblies: 1) a signaling incompetent structural NKp30-CD3ζ complex and 2) a ligand-induced signaling competent NKp30-CD3ζ complex. Moreover, we propose that ligand binding triggers translocation of Arg-143 from the membrane interface into the membrane to enable alignment with oppositely charged aspartate residues within CD3ζ and activation of CD3ζ-signaling.

Opening the Black Box of Cognitive-Behavioural Case Management in Clients with Ultra-High Risk for Psychosis.

BACKGROUND: Cognitive-behavioural therapy (CBT) is the first-choice treatment in clients with ultra-high risk (UHR) for psychosis. However, CBT is an umbrella term for a plethora of different strategies, and little is known about the association between the intensity and content of CBT and the severity of symptomatic outcome. METHODS: A sample of 268 UHR participants received 6 months of CBT with case management (CBCM) in the context of the multi-centre NEURAPRO trial with monthly assessments of attenuated psychotic symptoms (APS). Using multilevel regressions and controlling for the initial severity of APS, the associations between (1) number of CBCM sessions received and severity of APS and (2) specific CBCM components and severity of APS were investigated. RESULTS: In month 1, a higher number of sessions and more assessment of symptoms predicted an increase in APS, while in month 3, a higher number of sessions and more monitoring predicted a decrease in the level of APS. More therapeutic focus on APS predicted an overall increase in APS. CONCLUSIONS: Our findings indicate that the association between intensity/content of CBCM and severity of APS in a sample of UHR participants depends on the length of time in treatment. CBCM may positively impact the severity of APS later in the course of treatment. Therefore, it would seem important to keep UHR young people engaged in treatment beyond this initial period. Regarding the specific content of CBCM, a therapeutic focus on APS may not necessarily be beneficial in reducing the severity of APS, a possibility in need of further investigation.

Economic evaluation of an experience sampling method intervention in depression compared with treatment as usual using data from a randomized controlled trial.

BACKGROUND: Experience sampling, a method for real-time self-monitoring of affective experiences, holds opportunities for person-tailored treatment. By focussing on dynamic patterns of positive affect, experience sampling method interventions (ESM-I) accommodate strategies to enhance personalized treatment of depression-at potentially low-costs. This study aimed to investigate the cost-effectiveness of an experience sampling method intervention in patients with depression, from a societal perspective. METHODS: Participants were recruited between January 2010 and February 2012 from out-patient mental health care facilities in or near the Dutch cities of Eindhoven and Maastricht, and through local advertisements. Out-patients diagnosed with major depression (n = 101) receiving pharmacotherapy were randomized into: (i) ESM-I consisting of six weeks of ESM combined with weekly feedback regarding the individual's positive affective experiences, (ii) six weeks of ESM without feedback, or (iii) treatment as usual only. Alongside this randomised controlled trial, an economic evaluation was conducted consisting of a cost-effectiveness and a cost-utility analysis, using Hamilton Depression Rating Scale (HDRS) and quality adjusted life years (QALYs) as outcome, with willingness-to-pay threshold for a QALY set at €50,000 (based on Dutch guidelines for moderate severe to severe illnesses). RESULTS: The economic evaluation showed that ESM-I is an optimal strategy only when willingness to pay is around €3000 per unit HDRS and around €40,500 per QALY. ESM-I was the least favourable treatment when willingness to pay was lower than €30,000 per QALY. However, at the €50,000 willingness-to-pay threshold, ESM-I was, with a 46% probability, the most favourable treatment (base-case analysis). Sensitivity analyses confirmed the robustness of these results. CONCLUSIONS: We may tentatively conclude that ESM-I is a cost-effective add-on intervention to pharmacotherapy in outpatients with major depression. TRIAL REGISTRATION: Netherlands Trial register, NTR1974 .

Homo-oligomerization of the activating natural killer cell receptor NKp30 ectodomain increases its binding affinity for cellular ligands.

The natural cytotoxicity receptors, comprised of three type I membrane proteins NKp30, NKp44, and NKp46, are a unique set of activating proteins expressed mainly on the surface of natural killer (NK) cells. Among these, NKp30 is a major receptor targeting virus-infected cells, malignantly transformed cells, and immature dendritic cells. To date, only few cellular ligands of NKp30 have been discovered, and the molecular details of ligand recognition by NKp30 are poorly understood. Within the current study, we found that the ectodomain of NKp30 forms functional homo-oligomers that mediate high affinity binding to its corresponding cellular ligand B7-H6. Notably, this homo-oligomerization is strongly promoted by the stalk domain of NKp30. Based on these data, we suggest that homo-oligomerization of NKp30 in the plasma membrane of NK cells, which might be favored by IL-2-dependent up-regulation of NKp30 expression, provides a way to improve recognition and lysis of target cells by NK cells.

Assembly and function of the major histocompatibility complex (MHC) I peptide-loading complex are conserved across higher vertebrates.

Antigen presentation to cytotoxic T lymphocytes via major histocompatibility complex class I (MHC I) molecules depends on the heterodimeric transporter associated with antigen processing (TAP). For efficient antigen supply to MHC I molecules in the ER, TAP assembles a macromolecular peptide-loading complex (PLC) by recruiting tapasin. In evolution, TAP appeared together with effector cells of adaptive immunity at the transition from jawless to jawed vertebrates and diversified further within the jawed vertebrates. Here, we compared TAP function and interaction with tapasin of a range of species within two classes of jawed vertebrates. We found that avian and mammalian TAP1 and TAP2 form heterodimeric complexes across taxa. Moreover, the extra N-terminal domain TMD0 of mammalian TAP1 and TAP2 as well as avian TAP2 recruits tapasin. Strikingly, however, only TAP1 and TAP2 from the same taxon can form a functional heterodimeric translocation complex. These data demonstrate that the dimerization interface between TAP1 and TAP2 and the tapasin docking sites for PLC assembly are conserved in evolution, whereas elements of antigen translocation diverged later in evolution and are thus taxon specific.

A soluble fragment of the tumor antigen BCL2-associated athanogene 6 (BAG-6) is essential and sufficient for inhibition of NKp30 receptor-dependent cytotoxicity of natural killer cells.

Immunosurveillance of tumor cells depends on NKp30, a major activating receptor of human natural killer (NK) cells. The human BCL2-associated athanogene 6 (BAG-6, also known as BAT3; 1126 amino acids) is a cellular ligand of NKp30. To date, little is known about the molecular details of this receptor ligand system. Within the current study, we have located the binding site of NKp30 to a sequence stretch of 250 amino acids in the C-terminal region of BAG-6 (BAG-6(686-936)). BAG-6(686-936) forms a noncovalent dimer of 57-59 kDa, which is sufficient for high affinity interaction with NKp30 (KD < 100 nM). As our most important finding, BAG-6(686-936) inhibits NKp30-dependent signaling, interferon-γ release, and degranulation of NK cells in the presence of malignantly transformed target cells. Based on these data, we show for the first time that BAG-6(686-936) comprises a subdomain of BAG-6, which is sufficient for receptor docking and inhibition of NKp30-dependent NK cell cytotoxicity as part of a tumor immune escape mechanism. These molecular insights provide an access point to restore tumor immunosurveillance by NK cells and to increase the efficacy of cellular therapies.