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West, B.

Publications and source records attributed to West, B..

8 recordsLinked to original sources

From Single-Cell Emergent Behaviors to Clinical Outcome: PTEN-driven Migratory Efficiency as a Potential New Vulnerability in Glioblastoma

BackgroundGlioblastoma (GB) is a highly aggressive brain tumor with a median survival of approximately 14 months, primarily due to its ability to infiltrate healthy brain tissue both as single cells and in collectives. A deeper understanding of GB cell motility, both individual and collective, is crucial for developing patient-specific therapies. We aimed to characterize migration in patient-derived GB cells using advanced modeling to identify stratification markers and therapeutic vulnerabilities. MethodsWe developed Single-Cell Behavior Live Imaging (ScBLI), an approach integrating live imaging with computational analysis, applied to 30 GB primary cell cultures. Trajectories and morphological features were tracked and analyzed. Diffusion Entropy Analysis (DEA) was applied to classify trajectories based on the Delta Scaling parameter ({delta} scaling). We evaluated functional responses correlating all findings with clinical outcomes and transcriptomic profiles. ResultsWe analyzed 4,279 cell trajectories. Based on {delta} scaling (range 0.28-0.837), we defined three distinct motility groups: Low (L, {delta} scaling [&le;]0.5), Medium (M, 0.5 < {delta} scaling [&le;] 0.7), and High (H, {delta} scaling >0.7). Functional assays demonstrated that Group H cells are more performant in both positive and negative chemotaxis. Clinically, the three groups showed a clear linear progression with patient survival: High {delta} scaling correlated with the shortest survival (poorer prognosis), while Low {delta} correlated with the longest survival, suggesting that structured motility drives invasiveness. Integrative multi-omic analysis, encompassing both exome and transcriptome profiling, demonstrated that these groups are defined by distinct molecular landscapes rather than poor behavioral traits. Moreover, exome data revealed that Group H is significantly enriched in PTEN alterations (75% vs. 8% in Group L), with PTEN gain-of-function (GoF) mutations exclusively restricted to this group (100% vs 0% in Group L). Notably, within our extended cohort (n=51) currently characterized by whole-exome sequencing, we observed that specific PTEN GoF mutations were associated with a significantly shorter survival compared to PTEN wild-type cases (median OS 6.4 vs 16.6 months; p=0.02), which typically harbor the canonical loss of chromosome 10q. A similar clinical trend was observed when comparing directly GoF carriers to patients with truncating (Ter) alterations (median OS 6.4 vs 14.3 months; p=0.09). Conversely, no survival difference was found between truncating (Ter) mutations and wild-type cases. ConclusionOur findings demonstrate for the first time that migratory efficiency, quantified through DEA, represents a powerful predictor of glioblastoma aggressiveness. Tumor cells adopting highly efficient exploration strategies are strongly associated with poor clinical outcomes and are characterized by distinct molecular signatures, notably PTEN gain-of-function alterations. Statement of significanceOur multi-scale computational framework elucidates emergent behavioral phenotypes as pivotal drivers of glioblastoma progression. By demonstrating a correlation between enhanced migratory efficiency, PTEN gain-of-function, and significantly reduced overall survival, we establish a foundational paradigm for deciphering the emergent complexity governing tumor invasiveness.

cancer biology↗

Neutralization of recent SARS-CoV-2 variants by genetically and structurally related mAbs of the pemivibart lineage

Pemivibart is a monoclonal antibody therapy currently under Emergency Use Authorization for the for the pre-exposure prophylaxis of coronavirus disease 2019 (COVID-19) in adults and adolescents over 12 years of age with certain immunocompromised conditions. As a part of the overall monitoring strategy for the activity of pemivibart, the antibody is regularly evaluated against emerging variants of SARS-CoV-2 using pseudovirus neutralization assays. Recent clinical data from Invivyd demonstrates that the PhenoSense pseudovirus assays carried out at Monogram Biosciences have been a reliable and consistent predictor of continued pemivibart clinical activity against SARS-COV-2 variants that have predominated across the timespan that includes the CANOPY clinical trial and the post-EUA authorization period. Additionally, new potential antibodies based upon the structural framework of pemivibart are continuously under evaluation. Fifteen of these yeast-produced "pemivibart-like" antibodies were tested for neutralization activity against recent variants KP.3 and KP.3.1.1. Like pemivibart, all 15 maintained activity against KP.3.1.1, with the change in IC50 averaging 2.51-fold +/-0.7 compared to KP.3. Four pemivibart-like antibodies were also tested against the XEC variant, with the change in IC50 averaging 3.01-fold compared to KP.3. These data suggest continued activity for pemivibart and pemivibart-like antibodies against KP.3.1.1 and XEC, recent variants containing N-terminal domain modifications.

microbiology↗

Make Like a Tree and Leave: How Will Tree Species Loss and Climate Change Alter Future Temperate Broadleaved Forests?

Forest creation has the potential to reduce biodiversity loss and mitigate climate change but, tree disease emergence may counteract this. Further, given decadal timescales required for forest establishment, climate change is increasingly likely to act as a filter on plant community assembly. In the temperate lowlands succession takes 30 to 50 years for non-forest land to establish woodland plant assemblages, while the timescales required for new forest to sequester carbon suggest unassisted succession will be too slow for net zero 2050 targets. However, if plantations can establish faster than succession it would be beneficial to recommend planting native species as soon as possible. We explore scenarios of broadleaved woodland development across Wales, UK, as a case study area. We use a suite of empirical species niche models for British plants to estimate the potential species composition of forests with, and without, projected climate change. Additionally, we examine how tree canopy composition alters if Fraxinus excelsior is widely impacted by ash-dieback (Hymenoscyphus fraxineus). The results suggest soil total carbon and nitrogen could achieve baseline broadleaved forest values in less than 30 years. However only timber and woody flora species groups showed diversity surpassing baseline broadleaved forest diversity, with nectar plants and ancient woodland indicator species failing to reach baseline equivalents within 30 years; although complete congruence is unlikely given baseline forests could be hundreds of years old. Where Fraxinus excelsior was removed from the species pool we predicted that a scrub phase will persist or, if present, Acer pseudoplatanus will become the canopy dominant. The heavier shade cast this species is likely to result in differences in species composition of the understory and ground flora diversity is likely to decrease. Reliance on unassisted succession will also depend critically on (a) dispersal from local source populations and (b) on establishment filters that could be severe in landscapes with high management intensity history. These findings indicate that leaving the UKs fragmented habitats to relying on already degraded successional processes could lead to poor afforestation outcomes. HighlightsO_LIAfforestation can mitigate global change but tree disease makes outcomes uncertain C_LIO_LIAfforestation methods establishment timescales and time for benefits to occur C_LIO_LIWe model afforestation and predict how soils and plants change with climate C_LIO_LIAsh loss from die-back is replaced by low low-canopy woodland / scrub over 30 years C_LIO_LIAfforestation achieves baseline forest values for some variables within 30 years C_LI

ecology↗

Fractal Structure of Human and Primate Social Networks Optimizes Information Flow

Primate and human social groups exhibit a fractal structure that has a very limited range of preferred layer sizes, with groups of 5, 15, 50 and (in humans) 150 and 500 predominating. This same fractal distribution is also observed in the distribution of species mean group sizes in primates. Here we demonstrate that this preferential numbering arises because of the critical nature of dynamic self-organization within complex social networks. We calculate the size dependence of the scaling properties of complex social network models and argue that this aggregate behaviour exhibits a form of collective intelligence. Direct calculation establishes that the complexity of social networks as measured by their scaling behaviour is non-monotonic, peaking globally around 150 with a secondary peak at 500 and tertiary peaks centred on 15 and 50, thereby providing a theory-based rationale for the fractal layering of primate and human social groups.

animal behavior and cognition↗

Functional cooperativity mediated by rationally selected combinations of human monoclonal antibodies targeting the henipavirus receptor binding protein

Hendra virus (HeV) and Nipah virus (NiV), the prototypic members of the Henipavirus (HNV) genus, are emerging, zoonotic paramyxoviruses known to cause severe disease across six mammalian orders, including humans (Eaton et al., 2006). While several research groups have made strides in developing candidate vaccines and therapeutics against henipaviruses, such countermeasures have not been licensed for human use, and significant gaps in knowledge about the human immune response to these viruses exist. To address these gaps, we isolated a large panel of human monoclonal antibodies (mAbs) from the B cells of an individual with prior occupation-related exposure to the equine HeV vaccine (Equivac(R) HeV). Competition-binding and hydrogen-deuterium exchange mass spectrometry (HDX-MS) studies identified at least six distinct antigenic sites on the HeV/NiV receptor binding protein (RBP) that are recognized by human mAbs. Antibodies recognizing multiple antigenic sites potently neutralized NiV and/or HeV isolates in vitro. The most potent class of cross-reactive antibodies achieved neutralization by blocking viral attachment to the host cell receptors ephrin-B2 and ephrin-B3. Antibodies from this class mimic receptor binding by inducing a receptor-bound conformation to the HeV-RBP protein tetramer, exposing an epitope that appears to lie hidden in the interface between protomers within the HeV-RBP tetramer. Antibodies that recognize this cryptic epitope potently neutralized HeV and NiV. Flow cytometric studies using cell-surface-displayed HeV-RBP protein showed that cross-reactive, neutralizing mAbs from each of these classes cooperate for binding. In a highly stringent hamster model of NiVB infection, antibodies from both classes reduced morbidity and mortality and achieved synergistic protection in combination and provided therapeutic benefit when combined into two bispecific platforms. These studies identified multiple candidate mAbs that might be suitable for use in a cocktail therapeutic approach to achieve synergistic antiviral potency and reduce the risk of virus escape during treatment.

immunology↗

Assessing the pathogenicity, penetrance and expressivity of putative disease-causing variants in a population setting

Over 100,000 genetic variants are classified as disease-causing in public databases. However, the true penetrance of many of these rare alleles is uncertain and may be over-estimated by clinical ascertainment. As more people undergo genome sequencing there is an increasing need to assess the true penetrance of alleles. Until recently, this was not possible in a population-based setting. Here, we use data from 388,714 UK Biobank (UKB) participants of European ancestry to assess the pathogenicity and penetrance of putatively clinically important rare variants.\n\nAlthough rare variants are harder to genotype accurately than common variants, we were able to classify 1,244 of 4,585 (27%) putatively clinically relevant rare variants genotyped on the UKB microarray as high-quality. We defined \"rare\" as variants with a minor allele frequency of <0.01, and \"clinically relevant\" as variants that were either classified as pathogenic/likely pathogenic in ClinVar or are in genes known to cause two specific monogenic diseases in which we have some expertise: Maturity-Onset Diabetes of the Young (MODY) and severe developmental disorders (DD). We assessed the penetrance and pathogenicity of these high-quality variants by testing their association with 401 clinically-relevant traits available in UKB.\n\nWe identified 27 putatively clinically relevant rare variants associated with a UKB trait but that exhibited reduced penetrance or variable expressivity compared with their associated disease. For example, the P415A PER3 variant that has been reported to cause familial advanced sleep phase syndrome is present at 0.5% frequency in the population and associated with an odds ratio of 1.38 for being a morning person (P=2x10-18). We also observed novel associations with relevant traits for heterozygous carriers of some rare recessive conditions, e.g. heterozygous carriers of the R799W ERCC4 variant that causes Xeroderma pigmentosum were more susceptible to sunburn (one extra sunburn episode reported, P=2x10-8). Within our two disease subsets, we were able to refine the penetrance estimate for the R114W HNF4A variant in diabetes (only ~10% by age 40yrs) and refute the previous disease-association of RNF135 in developmental disorders.\n\nIn conclusion, this study shows that very large population-based studies will help refine the penetrance estimates of rare variants. This information will be important for anyone receiving information about their health based on putatively pathogenic variants.

genetics↗

Proximal recolonization by self-renewing microglia re-establishes microglial homeostasis in the adult mouse brain

Microglia are resident immune cells that play critical roles in maintaining normal physiology of the central nervous system. Remarkably, microglia have intrinsic capacity to replenish after being acutely ablated. However, the underlying mechanisms that drive such microglial restoration remain elusive. Here, we removed microglia via CSF1R inhibitor PLX5622 and characterized repopulation both spatially and temporally. We also investigated the cellular origin of repopulated microglia and report that microglia are replenished via self-renewal, with little contribution from non-microglial lineage progenitors, including nestin+ progenitors and the circulating myeloid population. Interestingly, spatial analyses with multi-color labeling reveal that newborn microglia recolonize the parenchyma by forming distinctive clusters that maintain stable territorial boundaries over time, indicating proximal expansion nature of adult microgliogenesis and stability of microglia tiling. Temporal transcriptome profiling from newborn microglia at different repopulation stages revealed that the adult newborn microglia gradually regain steady-state maturity from an immature state that is reminiscent of neonatal stage and follow a series of maturation programs that include NF-{kappa}B activation, interferon immune activation and apoptosis, etc. Importantly, we show that the restoration of microglial homeostatic density requires NF-{kappa}B signaling as well as apoptotic egress of excessive cells. In summary, our study reports key events that take place from microgliogenesis to homeostasis re-establishment.

neuroscience↗

A common allele in FGF21 associated with preference for sugar consumption lowers body fat in the lower body and increases blood pressure

Fibroblast Growth Factor 21 (FGF21) is a hormone that induces weight loss in model organisms. These findings have led to trials in humans of FGF21 analogues with some showing weight loss and lipid lowering effects. Recent genetic studies have shown that a common allele in the FGF21 gene alters the balance of macronutrients consumed but there was little evidence of an effect on metabolic traits. We studied a common FGF21 allele (A:rs838133) in 451,099 people from the UK Biobank study. We replicated the association between the A allele and higher percentage carbohydrate intake. We then showed that this allele is more strongly associated with body fat distribution, with less fat in the lower body, and higher blood pressure, than it is with BMI, where there is only nominal evidence of an effect. These human phenotypes of naturally occurring variation in the FGF21 gene will inform decisions about FGF21s therapeutic potential.

genetics↗