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Murray, J.

Publications and source records attributed to Murray, J..

At least 19 recordsLinked to original sources

Preclinical trial supports dual inhibition of BCL2 and Aurora kinase A for MYCN-amplified high-risk neuroblastoma

Purpose: Treatment for children with high-risk neuroblastoma relies on conventional chemotherapy and anti-GD2 immunotherapy. However, 5-year survival is only 50%, with high rates of late effects. Targeted therapy combinations are a major priority for these patients. The BCL2 inhibitor venetoclax, in combination with cyclophosphamide/topotecan, has clinical activity in relapsed and refractory neuroblastoma. We sought more effective and safer venetoclax combinations through systematic preclinical testing. Experimental design: Synergistic combinations were identified by high-throughput screening using patient-derived xenograft (PDX) models and confirmed in vivo. The leading combination (venetoclax-alisertib) was compared to combination chemotherapy in a clinical trial-like study using 22 PDX models, in scheduling experiments designed to reduce short-term toxicity, and in combination with anti-GD2 immunotherapy. BCL2 and Bim-BCL2 complex protein levels were assessed as predictors of sensitivity. Results: In vitro synergy with venetoclax was observed for standard-of-care chemotherapies and targeted agents, including DNA topoisomerase, microtubule, HDAC and Aurora kinase A (AURKA) inhibitors. Venetoclax-alisertib was particularly effective in vivo. In an n=1 study, venetoclax-alisertib induced objective response in all models. Activity was most striking in models of MYCN-amplified disease (n=12), doubling median survival time compared to cyclophosphamide/topotecan, and outperforming venetoclax-cyclophosphamide-topotecan. Efficacy was maintained with discontinuous schedules, minimizing hematological toxicity without substantially compromising activity. PDX-engrafted animals treated with venetoclax-alisertib and anti-GD2 immunotherapy survived tumor-free long-term. BCL2 expression and BCL2-Bim complex levels were of limited value for predicting response. Conclusion: Our findings support advancement of BCL2-AURKA inhibition to clinical trial for neuroblastoma with or without anti-GD2 immunotherapy, particularly in patients with MYCN amplified disease.

cancer biology↗

A cross-kingdom interactome predicted by AlphaFold3 reveals a DNF2-centered interface required for symbiotic accommodation

Legumes convert atmospheric nitrogen into ammonium through symbiotic bacteria housed in root nodules, yet the molecular interactions between rhizobial and host proteins inside nodules remain poorly understood. Here we employed AlphaFold3 to construct a cross-kingdom interactome between Medicago truncatula and its symbiont Sinorhizobium meliloti. Screening more than 217,000 protein pairs yielded 7,137 putative interactions, providing a valuable resource for the broader symbiosis community. Within this network, we focused on DEFECTIVE IN NITROGEN FIXATION 2 (DNF2), a host protein required for rhizobial persistence within nodules. We showed that DNF2 localizes to the peribacteroid space and associates with previously uncharacterized secreted rhizobial proteins (SRPs), suggesting it may function as a hub for host-symbiont communication. Notably, knockout of two DNF2-interacting proteins, SRP86 and SRP485, results in white, nitrogen-fixation-deficient nodules with abnormal symbiosomes and elevated expression of senescence-associated genes, closely phenocopying the dnf2 loss-of-function mutant. Together, our findings define a DNF2-SRP molecular framework underlying symbiotic accommodation, and illustrate the potential of AI-guided interactome mapping to uncover molecular mechanisms of plant-microbe interactions with relevance to sustainable agriculture.

plant biology↗

How Varenicline Works: Identifying Critical Receptor and Ligand-based Interactions

Approved by the FDA in 2006, varenicline became the first nicotinic-based therapeutic for smoking cessation and has since been used by tens of millions of smokers worldwide. Varenicline works by targeting the 4{beta}2 nicotinic acetylcholine receptor (nAChR), the primary focus for nicotine addiction, where ligand recognition by the receptor triggers ion channel opening. While widely recognized that vareniclines development was rooted in the well-established pharmacology of cytisine, the two compounds display notably different profiles, not only at nAChRs, but also at key off-target sites such as the 5-HT3 serotonin receptor. Despite vareniclines widespread use and proven efficacy as a smoking cessation aid, our knowledge of the precise molecular mechanism underlying its action, particularly the specific receptor-ligand interactions that underpin its functional specificity, remains incomplete. Through a multidisciplinary approach that integrates complementary fields of research, this study reveals the critical receptor-ligand interactions that distinguish varenicline from related nAChR agonists, such as cytisine and nicotine. Our findings reveal previously unrecognized, critical hydrogen bonding interactions within the 4{beta}2 binding sites, specifically involving 4T139, 4T183, and {beta}2S133, that are uniquely and selectively engaged by varenicline. Of these, {beta}2S133 emerged as the pivotal determinant of vareniclines function, with substitution by valine significantly impairing the ligand efficacy. Furthermore, the design and synthesis of novel varenicline analogues shed new light into the functional importance of the ligands quinoxaline moiety, revealing that not just the presence but also the precise positioning of this hydrogen bond acceptor are critical for receptor activation by varenicline. Together, these findings uncover a previously uncharacterized interaction network essential for vareniclines function at 4{beta}2, offering a deeper and more comprehensive framework for understanding its distinct pharmacological profile while expanding our broader understanding of how ligand binding is translated into function in these receptors. GRAPHICAL ABSTRACT O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=174 SRC="FIGDIR/small/659675v1_ufig1.gif" ALT="Figure 1"> View larger version (19K): org.highwire.dtl.DTLVardef@a77e39org.highwire.dtl.DTLVardef@4fec37org.highwire.dtl.DTLVardef@11d26a2org.highwire.dtl.DTLVardef@d35640_HPS_FORMAT_FIGEXP M_FIG C_FIG

pharmacology and toxicology↗

Public perception of dog emotional and motivational states in videos: A cross-sectional analysis

Recognition and interpretation of dogs emotional and motivational states from visual behavioural signs are important for public safety and dog welfare. This study used an online survey to explore the ability of members of the public (n = 4,133) to recognise the underlying emotional or motivational states of dogs in silent videos (n=30). Participants scored each video for nine pre-determined emotional and motivational states on a scale from 0 to 15 and rated the relative difficulty of scoring each video. Participants could also select "I am uncertain" for individual states which translated to missing values. Public scores were compared with those of eleven dog behaviour experts. The states "nervous/anxious", "stressed", "relaxed", "comfortable", "playful", "interested/curious", "excited", and "frustrated" showed high inter-expert agreement and were used in further analysis. "Boredom" was removed due to low inter-expert agreement. Principal components and cluster analyses on both datasets were used to collapse categories into two dimensions, identify groupings and compare overall perception. Results indicate similarity in perception of underlying states between public and experts. Correlation between expert difficulty rating, and both inter-expert agreement and public accuracy, indicates that experts effectively assessed the relative difficulty of determining underlying state. Members of the public perceived playful, excited, and curious dogs as easier to interpret than anxious and stressed dogs; however, this was not reflected in how accurately they scored videos (i.e., how different a participants scores were from the expert scores) and instead was reflected by how likely a participant was to score a video in full, rather than selecting that they were "uncertain" in response to any of the listed states. Findings of this study inform human behaviour change interventions to improve public interpretation of dog emotional and motivational states.

animal behavior and cognition↗

Learning decouples accuracy and reaction time for rapid decisions in a transitive inference task

Transitive inference (TI) is a cognitive process in which decisions are guided by internal representations of abstract relationships. While the mechanisms underlying transitive learning have been well studied, the dynamics of the decision-making process during learning and inference remain less clearly understood. In this study, we investigated whether a modeling framework traditionally applied to perceptual decision-making--the drift diffusion model (DDM)--can account for performance in a TI transfer task involving rapid decisions that deviate from standard accuracy and response time (RT) patterns. We trained six macaque monkeys on a TI transfer task, in which they learned the implied order of a novel list of seven images in each behavioral session, indicating their decisions with saccadic eye movements or reaching movements. Consistent learning of the list structure was achieved within 200-300 trials per session. Behavioral performance exhibited a symbolic distance effect, with accuracy increasing as the ordinal distance between items grew. Notably, RTs remained relatively stable across learning, despite improvements in accuracy. We applied a generalized DDM implementation (PyDDM; Shinn et al., 2020) to jointly fit accuracy and RT data. Model fits were achieved by incorporating both an increasing evidence accumulation rate and a collapsing decision bound, successfully capturing the RT distribution shapes observed during learning. Learning and transfer were fit by varying drift rate with little change in other parameters. Eye and reaching movements showed similar dynamics, with the difference in RT accounted for mainly by non-decision time. Our results highlight a distinct dynamical regime of the DDM framework, extending its applicability to cognitive domains involving symbolic reasoning and serial relational learning.

animal behavior and cognition↗

Transcriptional impacts of substance use disorder and HIV on human ventral midbrain neurons and microglia

For people with HIV (PWH), substance use disorders (SUDs) are a prominent neurological risk factor, and the impacts of both on dopaminergic pathways are a potential point of deleterious convergence. Here, we profile, at single nucleus resolution, the substantia nigra (SN) transcriptomes of 90 postmortem donors in the context of chronic HIV and opioid/cocaine SUD, including 67 prospectively characterized PWH. We report altered microglial expression for hundreds of pro- and anti-inflammatory regulators attributable to HIV, and separately, to SUD. Stepwise, progressive microglial dysregulation, coupled to altered SN dopaminergic and GABAergic signaling, was associated with SUD/HIV dual diagnosis and further with lack of viral suppression in blood. In virologically suppressed donors, SUD comorbidity was associated with microglial transcriptional changes permissive for HIV infection. We report HIV-related downregulation of monoamine reuptake transporters specifically in dopaminergic neurons regardless of SUD status or viral load, and additional transcriptional signatures consistent with selective vulnerability of SN dopamine neurons.

genomics↗

Chemically Induced Nuclear Pore Complex Protein Degradation via E3 Ligase TRIM21

Despite the exciting progress of the bifunctional degrader molecules, also known as proteolysis-targeting chimeras (PROTACs), the rapidly expanding field is still significantly hampered by the lacking of available E3 ligase ligands. Our research bridges this gap by uncovering a series of small-molecule ligands to the E3 ligase TRIM21 through DNA-Encoded Library (DEL) technology. We confirmed their interaction with TRIM21 using crystallography and demonstrated their anti-proliferative effects across various cancer cell types. Furthermore, proteomic studies identified that the mRNA Export Factor GLE1, and the Nuclear Pore Complex Protein NUP155, were significantly down-regulated upon TRIM21 ligand treatment. This degradation required TRIM21 and was ubiquitin-proteasome-dependent. More specifically, NUP155 was the primary target for the TRIM21 ligands, while GLE1 was considered a passenger target upon the initial degradation of NUP155. Using immunofluorescence techniques, we further demonstrated that the degradation of GLE1 and NUP155 proteins impaired the integrity of the nuclear envelope, leading to cell death. Highlighted by this research, a novel mode of action has been discovered for the TRIM21 E3 ligase ligand, acting as a monovalent degrader that triggers de novo interaction with functional complex proteins and induces their degradation.

cell biology↗

Genomic analyses correspond with deep persistence of peoples of Blackfoot Confederacy from glacial times

Mutually beneficial partnerships between genomics researchers and North American Indigenous Nations are rare. Here, we present one such partnership that provides insight into the peopling of the Americas and furnishes a new line of evidence that can be used to further treaty and Indigenous rights. We show that the genomics of sampled individuals from the Blackfoot Confederacy belong to a previously undescribed ancient lineage that diverged from other genomic lineages in the Americas in Late Pleistocene times. Using multiple complementary forms of knowledge, we provide a scenario for Blackfoot population history that fits with oral tradition and provides a plausible model for the evolutionary process of the peopling of the Americas. One-Sentence SummaryPreviously unknown genomic lineage in North America revealed in present-day Indigenous community and historic ancestors.

genomics↗

Dichotomy in TCR V-domain dynamics binding the opposed inclined planes of pMHC-II and pMHC-I α-helices

Ligand recognition by the human /{beta} T-cell antigen receptor (TCR) heterodimer protein, unlike the surface immunoglobulin (sIg) B-cell receptor, is not governed by relative binding affinity. Its interaction with the peptide (p) plus major histocompatibility complex (MHC) protein (abbrev. pMHC) likely involves some different molecular mechanism linking pMHC binding to T-cell functions. Recent analytical geometry of TCR:pMHC-II solved crystallographic structures (n = 40) revealed that each variable (V)-domain is bound in similar, yet mathematically unique orientations to its target pMHC groove. The relative position of the central cysteine of each V-domain was examined by multivariable calculus in spherical coordinates, where a simple volume element (dV) was found to describe clonotypic geometry with pMHC-II. Here, the study was expanded to include TCR:pMHC-I structures, and to model a physical mechanism, specifically involving the two directionally opposed inclined planes (IP) manifest by the two major -helices prominent in both MHC-I and MHC-II proteins. Calculations for rotational torque of each V-domain, together with acceleration up and down the slopes of both MHC -helices were used to estimate the time a given V-domain spends sliding down its cognate MHC IP. This V-domain rotation/sliding mechanism appears to be quantitatively unique for each TCR:pMHC V-domain (n = 40). However, there is an apparent and common dichotomy between the mobility of each V-domain with respect to the two classes of MHC proteins. Evolutionary motifs in the MHC helices support that the V-domains negotiate the opposed inclined planes of pMHC ligands in clonotypic fashion. Thus, this model is useful in understanding how mechanical forces are linked to TCR function.

immunology↗

Shark-dust: High-throughput DNA sequencing of processing residues unveils widespread trade in threatened sharks and rays

Illegal fishing, unregulated bycatch, and market demand for certain products (e.g. fins) are largely responsible for the rapid global decline of shark and ray populations. Controlling trade of endangered species remains difficult due to product variety, taxonomic ambiguity and trade complexity. The genetic tools traditionally used to identify traded species typically target individual tissue samples, are time-consuming and/or species-specific. Here, we performed high-throughput sequencing of trace DNA fragments retrieved from dust and scraps left behind by trade activities. We metabarcoded shark-dust samples from seven processing plants in the worlds biggest shark landing site (Java, Indonesia), and identified 54 shark and ray taxa (representing half of all chondrichthyan orders), half of which could not be recovered from tissue samples collected in parallel from the same sites. Importantly, over 80% of shark-dust sequences were found to belong to CITES-listed species. We argue that this approach is likely to become a powerful and cost-effective monitoring tool wherever wildlife is traded. One-Sentence SummaryShark-dust, the traces of biological material left behind from the processing of shark products, can now be DNA-sequenced in bulk to accurately reconstruct the biodiversity underlying trade.

genetics↗

Universal closed-tube barcoding for monitoring the shark and ray trade in megadiverse conservation hotspots

Trade restrictions for many endangered elasmobranch species exist to disincentivise their exploitation and curb their declines. However, the variety of products and the complexity of import/export routes make trade monitoring challenging. We investigate the use of a portable, universal, DNA-based tool which would greatly facilitate in-situ monitoring. We collected shark and ray samples across the Island of Java, Indonesia, and selected 28 species (including 22 CITES-listed species) commonly encountered in landing sites and export hubs to test a recently developed real-time PCR single-assay originally developed for screening bony fish. We employed a deep learning algorithm to recognize species based on DNA melt-curve signatures. By combining visual and machine learning assignment methods, we distinguished 25 out of 28 species, 20 of which were CITES-listed. With further refinement, this method can provide a practical tool for monitoring elasmobranch trade worldwide, without the need for a lab or the bespoke design of species-specific assays. HighlightsO_LIWe applied a portable, universal, closed-tube DNA barcoding approach originally developed for bony fishes to distinguish between shark and ray species traded in Indonesia. C_LIO_LIWe built a deep machine learning model to automatically assign species from the qPCR fluorescence spectra produced by two barcodes C_LIO_LIThe model achieved 79.41% accuracy for classifying 28 elasmobranch species, despite the barcode regions being designed for teleost species C_LIO_LIThis tool can serve as a potent single-assay in-situ diagnostic tool to regulate trade operations and it will be significantly enhanced by further optimisation of the barcode regions to fit elasmobranch DNA sequence variation C_LI

genetics↗

Multiple lineages of Monkeypox virus detected in the United States, 2021-2022

Monkeypox is a viral zoonotic disease endemic in Central and West Africa. In May 2022, dozens of non-endemic countries reported hundreds of monkeypox cases, most with no epidemiological link to Africa. We identified two lineages of Monkeypox virus (MPXV) among nine 2021 and 2022 U.S. monkeypox cases. A 2021 case was highly similar to the 2022 MPXV outbreak variant, suggesting a common ancestor. Analysis of mutations among these two lineages revealed an extreme preference for GA-to-AA mutations indicative of APOBEC3 cytosine deaminase activity that was shared among West African MPXV since 2017 but absent from Congo Basin lineages. Poxviruses are not thought to be subject to APOBEC3 editing; however, these findings suggest APOBEC3 activity has been recurrent and dominant in recent West African MPXV evolution.

genomics↗

Efficacy of Parainfluenza Virus 5 (PIV5)-vectored Intranasal COVID-19 Vaccine as a Single Dose Vaccine and as a Booster against SARS-CoV-2 Variants

Immunization with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines has greatly reduced coronavirus disease 2019 (COVID-19)-related deaths and hospitalizations, but waning immunity and the emergence of variants capable of immune escape indicate the need for novel SARS-CoV-2 vaccines. An intranasal parainfluenza virus 5 (PIV5)-vectored COVID-19 vaccine CVXGA1 has been proven efficacious in animal models and blocks contact transmission of SARS-CoV-2 in ferrets. CVXGA1 vaccine is currently in human clinical trials in the United States. This work investigates the immunogenicity and efficacy of CVXGA1 and other PIV5-vectored vaccines expressing additional antigen SARS-CoV-2 nucleoprotein (N) or SARS-CoV-2 variant spike (S) proteins of beta, delta, gamma, and omicron variants against homologous and heterologous challenges in hamsters. A single intranasal dose of CVXGA1 induces neutralizing antibodies against SARS-CoV-2 WA1 (ancestral), delta variant, and omicron variant and protects against both homologous and heterologous virus challenges. Compared to mRNA COVID-19 vaccine, neutralizing antibody titers induced by CVXGA1 were well-maintained over time. When administered as a boost following two doses of a mRNA COVID-19 vaccine, PIV5-vectored vaccines expressing the S protein from WA1 (CVXGA1), delta, or omicron variants generate higher levels of cross-reactive neutralizing antibodies compared to three doses of a mRNA vaccine. In addition to the S protein, the N protein provides added protection as assessed by the highest body weight gain post-challenge infection. Our data indicates that PIV5-vectored COVID-19 vaccines, such as CVXGA1, can serve as booster vaccines against emerging variants. ImportanceWith emerging new variants of concern (VOC), SARS-CoV 2 continues to be a major threat to human health. Approved COVID-19 vaccines have been less effective against these emerging VOCs. This work demonstrates the protective efficacy, and strong boosting effect, of a new intranasal viral-vectored vaccine against SARS-CoV-2 variants in hamsters.

microbiology↗

Two snakebite antivenoms have potential to reduce Eswatini's dependency upon a single, increasingly unavailable product: results of preclinical efficacy testing

BackgroundSnakebite is a major public health concern in Eswatini, where treatment relies upon one antivenom - SAIMR Polyvalent. Although effective in treating snakebite, SAIMR Polyvalent is difficult to source outside its manufacturing country (South Africa) and is dauntingly expensive. We compared the preclinical venom-neutralising efficacy of two alternative antivenoms and SAIMR Polyvalent against the lethal and tissue-destructive effects of venoms from five species of medically important snakes using in vivo murine assays. The test antivenoms were Panafrican manufactured by Instituto Clodomiro Picado and PANAF manufactured by Premium Serums & Vaccines. Principal FindingsIn vivo murine preclinical studies identified both test antivenoms were equally or more effective than SAIMR Polyvalent at neutralising lethal and tissue-destructive effects of Naja mossambica venom. Both test antivenoms were less effective than SAIMR Polyvalent at neutralising the lethal effects of Bitis arietans, Dendroaspis polylepis, Hemachatus haemachatus and Naja annulifera venoms, but similarly effective at neutralising tissue damage induced by B. arietans and H. haemachatus venoms. In vitro immunological assays identified that IgG titres and toxin-specificities of the test antivenoms were comparable to SAIMR Polyvalent. Plasma clotting disturbances by H. haemachatus and N. mossambica were effectively neutralised by the test antivenoms, whereas SAIMR Polyvalent failed to neutralise this bioactivity of N. mossambica venom. The SVMP activity of B. arietans venom was equally reduced by all three antivenoms. The PLA2 activities of H. haemachatus and N. mossambica were effectively neutralised by all three antivenoms. ConclusionsPanafrican outperformed PANAF, though both were less poly-specifically effective than SAIMR Polyvalent. The efficacy of these antivenoms against the lethal and tissue-destructive effects of N. mossambica venom, the most common biting species in Eswatini, identify that Panafrican and PANAF antivenoms offer effective alternatives to SAIMR for the treatment of snakebite in Eswatini, and potentially for neighbouring countries. Author SummaryTreatment of snakebite in Eswatini is reliant upon a single antivenom (SAIMR Polyvalent) manufactured in South Africa. This highly effective product is increasingly difficult to source and is expensive - alternative/additional antivenoms are urgently required to improve patient outcomes following snake envenoming. Using murine preclinical venom toxicity and antivenom efficacy assays, we identified two alternative antivenoms whose venom-neutralising characteristics, while less poly-specifically effective than SAIMR Polyvalent, were as effective against the lethal and tissue-destructive effects of the most common biting snake in Eswatini - Naja mossambica. This murine data, already shared with the Eswatini Ministry of Health, supports and justifies human testing of these two antivenoms in Eswatini because increasing the availability of effective and affordable treatments could resolve the current medical dependency of Eswatini snakebite patients upon a single, rarely available and expensive product.

pharmacology and toxicology↗

The peptide GOLVEN10 controls nodule and lateral root organogenesis and positioning along the longitudinal root axis

O_LIGLV/RGF peptide encoding genes can be identified in genomes of all plants that can form roots or root-like structures suggesting they were essential for transition of plants to land. C_LIO_LIIn Medicago truncatula, five of fifteen GOLVEN(GLV)/ROOT MERISTEM GROWTH FACTOR (RGF) peptide coding genes were induced during nodule organogenesis and to a varying extent under nitrogen deficiency and auxin treatment. Expression of MtGLV9 and MtGLV10 at nodule initiation sites was dependent on the transcription factor NODULE INCEPTION. C_LIO_LIOverexpression of all five nodule-induced GLV genes in M. truncatula hairy roots as well as application of the corresponding synthetic peptides resulted in a 25-50% reduction in nodule number indicating GOLVENs are negative regulators of nodule organogenesis. C_LIO_LIThe peptide GOLVEN10 shifted the position of the first formed lateral root (rhizotaxis) as well as the first formed nodule along the longitudinal primary root axis, a phenomenon we term nodulotaxis, thereby reducing the absolute length of the zone of lateral organ formation on roots. C_LIO_LIApplication of synthetic GOLVEN10 peptide caused an increase in cell number but not cell length in each root cortical cell layer causing an increase in root length and a consequent spatiotemporal delay in formation of the first lateral organ. C_LI Plain Language SummaryNodule positioning is an understudied trait, yet it determines the length of the root that can support nodule formation and consequently the total number of functional nodules formed. We identify for the first time, genetic factors called GOLVEN peptides that alter nodule and lateral root positioning on the primary root along with several other traits including nodule organ initiation and root architecture.

plant biology↗

HIV integration in the human brain is linked to microglial activation and 3D genome remodeling

Exploration of genome organization and function in the HIV infected brain is critical to aid in the development of treatments for HIV-associated neurocognitive disorder (HAND) and HIV cure strategies. Here, we generated a resource comprised of single nuclei transcriptomics, complemented by cell-type-specific Hi-C chromosomal conformation ( 3D genome) and viral integration site sequencing (IS-seq) in frontal brain tissues from individuals with HIV encephalitis (HIVE), HIV-infected people without encephalitis (HIV+), and HIV uninfected (HIV-) controls. We observed profound 3D genomic reorganization of open/repressive (A/B) compartment structures encompassing 6.4% of the HIVE microglial genome that was associated with transcriptomic reprogramming, including down-regulation of homeostasis and synapse-related functions and robust activation of interferon signaling and cell migratory pathways. HIV RNA was detected in 0.003% of all nuclei in HIVE brain, predominantly in the most activated microglia where it ranked as the second most highly expressed transcript. Microglia from HIV+ brains showed, to a lesser extent, similar transcriptional alterations. IS-seq recovered 1,221 insertion events in glial nuclei that were enriched for chromosomal domains newly mobilized into a permissive chromatin environment in HIVE microglia. Brain and peripheral myeloid cell integration revealed a preference overall for transcription-permissive chromatin, but robust differences in the frequency of recurrent insertions, intergenic integration, and enrichment for pre-integration complex-associated factors at integration sites. Our resource highlights critical differences in the genomic patterns of HIV infection in brain versus blood and points to a dynamic interrelationship between inflammation-associated 3D genome remodeling and successful integration in brain.

neuroscience↗

Structural basis for ultrapotent neutralization of human metapneumovirus

Human metapneumovirus (hMPV) is a leading cause of morbidity and hospitalization among children worldwide, however, no vaccines or therapeutics are currently available for hMPV disease prevention and treatment. The hMPV fusion (F) protein is the sole target of neutralizing antibodies. To map the immunodominant epitopes on the hMPV F protein, we isolated a panel of human monoclonal antibodies (mAbs), and the mAbs were assessed for binding avidity, neutralization potency, and epitope specificity. We found the majority of the mAbs target diverse epitopes on the hMPV F protein, and we discovered multiple mAb binding approaches for antigenic site III. The most potent mAb, MPV467, which had picomolar potency, was examined in prophylactic and therapeutic mouse challenge studies, and MPV467 limited virus replication in mouse lungs when administered 24 hrs before or 72 hrs after viral infection. We determined the structure of MPV467 in complex with the hMPV F protein using cryo-electron microscopy to a resolution of 3.3 [A], which revealed a complex novel prefusion-specific epitope overlapping antigenic sites II and V on a single protomer. Overall, our data reveal new insights into the immunodominant antigenic epitopes on the hMPV F protein, identify a new mAb therapy for hMPV F disease prevention and treatment, and provide the discovery of a unique pre-fusion-specific epitope on the hMPV F protein.

immunology↗

Probenecid Inhibits SARS-CoV-2 Replication In Vivo and In Vitro

Effective vaccines are slowing the COVID-19 pandemic, but SARS-CoV-2 will likely remain an issue in the future making it important to have therapeutics to treat patients. There are few options for treating patients with COVID-19. We show probenecid potently blocks SARS-CoV-2 replication in mammalian cells and virus replication in a hamster model. Furthermore, we demonstrate that plasma concentrations up to 50-fold higher than the protein binding adjusted IC90 value are achievable for 24h following a single oral dose. These data support the potential clinical utility of probenecid to control SARS-CoV-2 infection in humans.

microbiology↗