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Beck, S.

Publications and source records attributed to Beck, S..

At least 19 recordsLinked to original sources

Multiparametric in vivo mapping reveals tissue-specific mitochondrial aging trajectories

Mitochondrial dysfunction is a hallmark of aging, yet how mitochondrial states are remodeled across tissues and subcellular compartments in vivo remains elusive. Progress has been limited, in part, because mitochondrial physiology is highly sensitive to experimental perturbations, underscoring the need for minimally disruptive measurement strategies. Here, we establish a tissue-resolved, in vivo framework for the quantitative analysis of mitochondrial states in live, intact Caenorhabditis elegans without confounding effects from mounting-induced hypoxia. This platform couples two-photon fluorescence lifetime imaging microscopy (2p-FLIM) with a custom segmentation pipeline, MitoSLIT, to track functional and structural features across multiple tissues and single neurons. By integrating membrane potential-associated TMRM intensity, lifetime-based microenvironmental metrics, and morphological descriptors, we uncover localized metabolic heterogeneity masked by conventional intensity analysis. Leveraging this framework, we mapped physiological aging against mitochondrial shifts induced by acute stress and fission-fusion mutations. Our analyses reveal that mitochondrial aging is highly tissue-specific, executing distinct trajectories across cell types. Extending the framework to genetically identified neurons revealed age-dependent divergence between somatic and axonal mitochondrial states, accompanied by structural remodeling and a late shift in optical redox ratio. Together, our findings demonstrate that mitochondrial populations do not converge on a uniform bioenergetic endpoint during aging, but rather follow highly compartmentalized, tissue-specific spatiotemporal trajectories in vivo.

physiology↗

Loop-Directed Cofactor Binding Enables Programmable Multico-factor Protein Design

The emergence of respiratory, photosynthetic, and assimilatory complexes in evolution required proteins capable of binding multiple catalytic and electron-transfer cofactors while exerting fine control over their spatial arrangement. Across natural systems these cofactors are preferentially positioned in loop regions. In contrast, most protein design strategies have focused on installing cofactor-binding sites within helical elements. Here we show that introducing only a pair of appropriately placed histidine ligands into the interhelical loop regions of a canonical single-chain four-helix bundle is sufficient to create new well-defined high affinity heterocofactor binding sites. This simple modification enables the self-assembly of complexes containing up to three distinct cofactors in a single designed domain with positional specificity. Using this strategy, we created constructs containing one or two hemes in combination with Zn(II)-phthalocyanine monosulfonate, Zn-heme, and the light-harvesting Zn(II)-tetraphenylporphyrin tetrasulfonate. Fluorescence measurements of constructs containing the latter show efficient energy transfer between photoactive donor cofactors. By demonstrating that loop-embedded ligands support robust, modular, and evolutionarily plausible cofactor recruitment, this work provides a mechanistic explanation for the widespread placement of redox and catalytic cofactors in loops in natural proteins: only limited packing complementarity is needed, meaning that just a few mutations can introduce a functional cofactor binding site, after which additional mutations can tune affinity, reactivity, and specificity. More importantly, it establishes a straightforward path toward constructing functional protein domains that mirror the complexity of biological energy-conversion architectures. TOC Graphic O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=103 SRC="FIGDIR/small/734619v1_ufig1.gif" ALT="Figure 1"> View larger version (37K): org.highwire.dtl.DTLVardef@e48a58org.highwire.dtl.DTLVardef@36b289org.highwire.dtl.DTLVardef@1034495org.highwire.dtl.DTLVardef@18bb284_HPS_FORMAT_FIGEXP M_FIG C_FIG

biophysics↗

Targeting platelet GPVI or GPIIb/IIIa only minimally affect acute inflammation and cardiac repair in experimental permanent myocardial infarction

BackgroundBeyond their role in hemostasis, platelets are recognized as key regulators of inflammatory responses in ischemic diseases, including cardiac ischemia/reperfusion (I/R) injury with key roles of platelet membrane glycoproteins (GP)VI and IIb/IIIa. However, whether platelet-driven thrombo-inflammatory pathways affect acute inflammation and cardiac repair processes in permanent, non-reperfused myocardial infarction (MI) is unknown. MethodsWe targeted GPVI and GPIIb/IIIa in experimental permanent MI in mice. Cardiac, bone marrow, and blood innate immune responses were evaluated by flow cytometry and single-cell RNA-sequencing. Survival and cardiac repair were assessed over the inflammatory and scar formation phase, until day 10 after permanent MI. ResultsPlatelet GPVI immunodepletion by injection of the anti-GPVI antibody JAQ1 did not affect levels of neutrophil or monocyte subsets (Ly6Chi and Ly6Clow) in the bone marrow and blood, and did not alter accumulation of monocytes, macrophage subsets (defined by expression of MHCII and TIM4), or neutrophil subsets (SiglecFhi/low) in the infarcted heart on day 4. GPVI depletion only had a minimal effect on cardiac repair, slightly decreasing interstitial fibrosis in the infarct border zone on day 10. Four days after MI, GPIIb/IIIa inhibition by JON/A-F(ab')2 had no effect on cardiac or systemic innate immune cell levels as measured by flow cytometry and did not affect composition and transcriptomic profile of the cardiac immune infiltrate as revealed by single-cell RNA-sequencing. GPIIb/IIIa inhibition did not improve cardiac remodeling, and was even associated with an increased mortality rate over 10 days post-MI. ConclusionTargeting the GPVI-GPIIb/IIIa axis only had minor effects on post-MI inflammatory responses and cardiac wound healing in permanent myocardial ischemia. Our findings demonstrate that the therapeutic benefits of inhibiting platelet-driven thrombo-inflammation are particularly relevant in the subacute reperfusion phase.

physiology↗

GIMMEcpg: Global Imputation of Mean CpG MEthylation in Real-time

Whole-genome DNA methylation (methylome) analysis is of broad interest to biomedical research due to its central role in human development and disease. However, generating high-quality methylomes at scale remains challenging due to inherent technical limitations. While imputation has the potential to help overcome this problem, no existing approach adequately addresses the scaling issue. Here, we present GIMMEcpg (Global Imputation of Mean cpg MEthylation), a novel imputation tool that scales efficiently from single samples to large cohort studies. GIMMEcpg uses a custom feature dataset built from known CpG sites within the same dataset to impute missing values by calculating the distance-weighted mean of the methylation value of the two immediately neighbouring CpG sites. We benchmarked GIMMEcpg for speed and accuracy against multiple imputation methods using downsampled datasets produced from high-quality ([~]100x) Whole Genome Bisulfite Sequencing (WGBS) data. With a 10x downsampled dataset, GIMMEcpg was able to process the dataset and impute 9.14 Million CpG sites within 7 seconds (R: 0.78, MAE: +5.6%, RMSE: +10.9%). Our results demonstrate that GIMMEcpg is 39-2,562 times faster than three existing methylation imputation tools (BoostMe, DeepCpG, and MethImpute) while maintaining comparable accuracy. To quantify GIMMEcpgs scalability, we applied it to the most extensive single collection of WGBS data (N=645 at variable coverage) from the EpiATLAS generated by the International Human Epigenome Consortium (IHEC). Using a single, standard CPU server, GIMMEcpg processed and imputed an additional 2.4 billion CpG methylation values across the 645 datasets in less than a day, enriching the EpiATLAS methylome resource by 20%. This demonstrates that GIMMEcpg scales to large cohort studies with only a subtle impact on accuracy, as illustrated by our benchmark. We also developed a machine learning variant, GIMMEcpg.ml, which delivers a higher accuracy compared to existing methodologies. Using the same 10x downsampled benchmarking dataset, GIMMEcpg.ml achieved a Person Correlation of 0.87 compared to the ground truth, representing an improvement of 0.11 over the best performing alternative method. Additionally, GIMMEcpg.ml has a Mean Absolute Error (MAE) of 8.67%, which is 2.63% lower than the most accurate performing alternative. While this enhanced accuracy comes at the cost of increased computation requirements, GIMMEcpg.ml is a useful tool where higher accuracy is preferred over scalability. For increased accessibility, GIMMEcpg is freely available under an MIT license as R and Python packages at https://github.com/ucl-medical-genomics/gimmecpg-r and https://github.com/ucl-medical-genomics/gimmecpg-python, respectively.

bioinformatics↗

Snapshot of in-cell protein contact sites reveals new host factors and hijacking of paraspeckles during influenza A virus infection

Influenza A virus (IAV) hijacks host cellular machinery, but many virus-IAV interactions and contacting protein sites remain uncharacterised, particularly those dependent on intact cellular architecture, such as membrane-associated or phase-separated compartments. Here, we applied in-cell cross-linking mass spectrometry (XL-MS), integrated with AlphaFold-based structural modelling and functional assays, to map protein-protein contact sites in IAV-infected human cells. This approach revealed previously unrecognised virus-host interactions linked to spatially organised processes, including the maturation pathway of HA through the membrane-bound ER- Golgi system, the novel interaction of M2 with the membrane-embedded LAT1 amino acid transporter, and the progressive disassembly of paraspeckles-phase-separated compartments in the nucleus. We validate M2-LAT1 interaction and paraspeckle disassembly in human primary lung epithelial cells and show that the paraspeckle disassembly constitutes a new and unique infection mechanism through which IAV releases RNA-binding proteins that support viral RNA replication. These findings advance the understanding of IAV manipulation of host cellular processes and illustrate how the integrative in-cell structural system biology approach captures native host-pathogen interactomes, infection pathways, and host cell perturbations.

microbiology↗

A high-quality genomic catalog of the human oral microbiome broadens its phylogeny and clinical insights

Understanding the taxonomic and functional diversity of the human oral microbiome requires comprehensive genomic catalogs. We present the human reference oral microbiome (HROM), with 72,641 high-quality genomes from 3,426 species, including 2,019 novel species, significantly improving metagenomic sequence read classification over existing catalogs. Notably, HROM unveils 1,137 novel candidate phyla radiation (CPR) species, establishing Patescibacteria as the most prevalent phylum in the oral microbiota, with oral Patescibacteria forming a distinct clade from environmental Patescibacteria. We also identify an oral CPR subclade associated with periodontitis, which complement Porphyromonas gingivalis in predicting the disease. Finally, comparing HROM with reference genomes of the human gut microbiome reveals significant taxonomic and functional divergence between the oral and gut microbiomes. We identify 42 ectopic oral species and demonstrate that their relative abundance in gut microbiota is predictive of intestinal, cardiovascular, and liver diseases, highlighting the clinical importance of the oral microbiota in systemic disorders.

microbiology↗

The CoREST complex inhibitor, corin, leads to decreased tumor growth, increased cellular differentiation and extended lifespan in atypical teratoid rhabdoid tumor xenograft models

BackgroundAtypical teratoid rhabdoid tumor (ATRT) is the most common malignant brain tumor in infants, and more than 60% of children with ATRT die from their tumor. ATRT is associated with mutational inactivation/deletion of SMARCB1, a member of the SWI/SNF chromatin remodeling complex, suggesting that epigenetic events play a critical role in tumor development and progression. Moreover, disruption of SWI/SNF allows unopposed activity of epigenetic repressors, which contribute to tumorigenicity. We therefore explored the role of the CoREST repressor complex in ATRT. MethodsWe evaluated the effects of the bifunctional LSD1/HDAC1/2 small molecule CoREST inhibitor, corin, on ATRT tumor cell growth, apoptosis, differentiation, gene expression and chromatin accessibility. ResultsWe found that corin inhibited the growth of ATRT cells regardless of their epigenetic subgroup, and was associated with increased tumor cell apoptosis and differentiation. ATAC-seq showed increases in chromatin accessibility in corin-treated ATRT cells, with changes seen at genes associated with neuronal differentiation and synaptic function. RNA-seq confirmed increased expression of neuronal differentiation genes and decreased DNA replication/cell cycle-associated genes in ATRT cells treated with corin. Corin suppressed orthotopic ATRT tumor growth, leading to significant extension of lifespan. In addition, increased histone acetylation (H3K9ac, H3K27ac) and methylation (H3K4Me1) was seen in corin-treated ATRT orthotopic xenografts, consistent with on-target pharmacodynamics. ConclusionThe CoREST inhibitor, corin, suppresses tumor growth, induces differentiation, and promotes apoptosis in ATRT, leading to significantly increased survival of mice bearing ATRT orthotopic xenografts. Our results suggest a potential application of CoREST complex inhibitors in patients with ATRT. Key PointsO_LICoREST complex inhibition by corin leads to decreased cell growth and increased apoptosis in ATRT C_LIO_LICorin promotes chromatin accessibility and neuronal differentiation in ATRT C_LIO_LICorin inhibits tumor growth and extends lifespan in ATRT animal models C_LI Importance of the StudyLoss of function of SMARCB1 is a hallmark of ATRT which leads to dysfunction of the mammalian SWI/SNF complex and an inability to counteract epigenetic repressor complexes. The CoREST complex functions as a chromatin remodeling complex that represses neuronal differentiation genes during development. Inhibition of the CoREST complex by corin in ATRT leads to decreased tumor cell growth, induction of apoptosis and increased survival of mice bearing ATRT orthotopic xenografts. These changes are associated with increased chromatin accessibility and expression of genes associated with neuronal differentiation. Corin therefore reverses the primary block of differentiation that maintains a stem cell state in ATRT, which contributes to tumorigenesis. These studies significantly improve our understanding of how to therapeutically address the underlying epigenetic drivers of ATRT and support further development of corin for ATRT.

cancer biology↗

Exclusive cataloging of near-complete genomes unveils novel functional insights into the human gut microbiome

Understanding the human gut microbiome requires comprehensive genomic catalogues, yet many lack geographic diversity and contain medium-quality metagenome-assembled genomes (MAGs) missing up to 50% of genomic regions, potentially distorting functional insights. Here, we describe an enhanced Human Reference Gut Microbiome (HRGM2) resource, a catalogue of near-complete MAGs ([≥]90% completeness, [≤]5% contamination) and isolate genomes. HRGM2 comprises 155,211 non-redundant near-complete genomes from 4,824 prokaryotic species across 41 countries, representing a 66% increase in genome count and a 50% boost in species diversity compared to the Unified Human Gastrointestinal Genome catalogue. It enabled improved DNA-based species profiling, resolution of strain heterogeneity, and survey of human gut resistome. The exclusive use of these genomes improved metabolic capacity assessment enabling high-confidence, automated genome-scale metabolic models (GEMs) of the entire microbiota, revealing disease-associated microbial metabolic interactions. This resource will facilitate reliable functional insights into gut microbiomes.

microbiology↗

Epigenetic investigation of multifocal small intestinal neuroendocrine tumours reveals accelerated ageing of tumours and epigenetic alteration of metabolic genes

BackgroundSmall intestinal neuroendocrine tumours (SI-NETs) are the most common malignancy of the small intestine and around 50% of patients present in clinic with multifocal disease. Recent investigations into the genomic architecture of multifocal SI-NETs have found evidence that these synchronous primary tumours evolve independently of each other. They also have extremely low mutational burden and few known driver genes, suggesting that epigenetic dysregulation may be driving tumorigenesis. Very little is known about epigenetic gene regulation, metabolism and ageing in these tumours, and how these traits differ across multiple tumours within individual patients. MethodsIn this study, we performed the first investigation of genome-wide DNA methylation in multifocal SI-NETs, assessing multiple primary tumours within each patient (n=79 primary tumours from 14 patients) alongside matched metastatic tumours (n=12) and normal intestinal epithelial tissue (n=9). We assessed multifocal SI-NET differential methylation using a novel method, comparing primary tumours with matched normal epithelial tissue and an enterochromaffin-enriched cell line to enrich for tumour-specific effects. This method reduced the identification of false positive methylation differences driven by cell composition differences between tumour and normal epithelial tissue. We also assessed tumour ageing using epigenetic clocks and applied metabolic predictors in the dataset to assess methylation variation across key metabolic genes. ResultsWe have identified 12,392 tumour-specific differentially methylated positions (Bonferroni corrected p<0.05) which were enriched for neural pathways. The expression levels of the genes associated with top sites were also found to be significantly altered in SI-NETs. Age acceleration was observed across SI-NETs and a variability in epigenetic age of tumours within each patient, which we believe is reflecting the order in which tumours have developed. This is supported by the correlation of age acceleration with somatic mutational count in the tumours. We have identified SI-NET associated alterations to the methylation patterns in key metabolic genes compared to matched normal tissue, which is more pronounced in metastatic tumours and tumours harbouring chromosome 18 loss of heterozygosity, indicating metabolic differences in these tumour subtypes. ConclusionsWe have identified accelerated ageing and changes to regulation of metabolic genes, alongside an epigenetic signature of multifocal SI-NETs. These findings add to our understanding of multifocal SI-NET biology and their molecular differences which may be instrumental in the development of these elusive tumours.

cancer biology↗

Role of CCK1 receptor in metabolic benefits of intestinal enteropeptidase inhibition in mice

Enteropeptidase (EP; enterokinase) is a serine protease that regulates intestinal protein digestion by converting trypsinogen into active trypsin, and thus initiates activation of the pancreatic zymogen cascade. Chronic inhibition of EP and trypsin (EP/T) with camostat (Foipan, FOY-305) or its active metabolite (FOY-251) causes weight loss in obese mice by reducing intestinal protein absorption and suppression of food intake, however, the mechanisms leading to appetite suppression are not well understood. We tested the hypothesis that cholecystokinin (CCK) signaling mediates the anorectic effects of EP/T inhibition using a CCK1R inhibitor (loxiglumide) or CCK1R knockout (KO) mice. Acute treatment with loxiglumide was able to partially reverse FOY-251-induced gallbladder contraction and delayed gastric emptying in mice. Chronic co-administration of loxiglumide reversed FOY-251 mediated effects on food intake and metabolism in diet-induced obese (DIO) mice. Chronic dosing of FOY-251 caused similar reductions in food intake but greater weight loss in CCK1R KO mice compared to wildtype (WT) mice, primarily due to fat mass loss. Pair fed (PF) groups revealed food intake-dependent and -independent mechanisms of weight loss by FOY-251. Notably, FOY-251 treatment induced sustained weight loss, whereas body weight loss rebounded in PF animals. In CCKR1 KO mice, FOY-251 caused greater weight loss, and increased protein calorie loss relative to that in WT mice, while having no effect on glycemic control or FGF21. Hence, CCK1R-dependent and - independent mechanisms modulate the metabolic effects of EP/T inhibition and may play a role in maintaining weight loss by this mechanism.

pharmacology and toxicology↗

Bisphenol TMC disturbs mitochondrial activity and biogenesis, reducing lifespan and healthspan in the nematode Caenorhabditis elegans

Rising concerns about Bisphenol A (BPA) toxicity have prompted the search for safer alternatives. However, concerns persist regarding the safety of replacements like bisphenol TMC (BPTMC), a rapidly emerging BPA substitute. Utilizing the in vivo model organism Caenorhabditis elegans (C. elegans), whose shared genes mirror human biology, we aim to unveil the potential toxicity of BPTMC on a live animal. C. elegans exposed to 1 mM BPTMC exhibited developmental delays, reduced reproduction, and diminished longevity. Furthermore, an investigation into mortality at various animal stages, oxidative stress, and thermal stress revealed additional compromised toxicity. Notably, exposure to BPTMC resulted in mitochondrial abnormalities, including reduced oxygen consumption, lowered mitochondrial membrane potential, and decreased ATP levels. Additionally, BPTMC increased ROS levels but decreased mitochondrial population. Transcriptome analysis revealed that BPTMC induces alterations in the expression of genes associated with mitochondrial biogenesis. Our findings raise crucial concerns about BPTMC as a safe BPA alternative. The observed widespread toxicity across key life stages suggests a need for further investigation into the potential toxicity of BPTMC on human health and environmental consequences.

pharmacology and toxicology↗

Open access-enabled evaluation of epigenetic age acceleration in colorectal cancer and development of a classifier with diagnostic potential.

Aberrant DNA methylation (DNAm) is known to be associated with the aetiology of cancer, including colorectal cancer (CRC). In the past, the availability of open access data has been the main driver of innovative method development and research training. However, this is increasingly being eroded by the move to controlled access, particularly of medical data, including cancer DNAm data. To rejuvenate this valuable tradition, we leveraged DNAm data from 1,845 samples (535 CRC tumours, 522 normal colon tissues adjacent to tumours, 72 colorectal adenomas, and 716 normal colon tissues from healthy individuals) from 14 open access studies deposited in NCBI GEO and ArrayExpress. We calculated each samples epigenetic age (EA) using eleven epigenetic clock models and derived the corresponding epigenetic age acceleration (EAA). For EA, we observed that most first- and second-generation epigenetic clocks reflect the chronological age in normal tissues adjacent to tumours and healthy individuals (e.g. Horvath (r = 0.77 and 0.79), Zhang EN (r = 0.70 and 0.73)) unlike the epigenetic mitotic clocks (EpiTOC, HypoClock, MiAge) (r < 0.3). For EAA, we used PhenoAge, Wu, and the above mitotic clocks and found them to have distinct distributions in different tissue types, particularly between normal colon tissues adjacent to tumours and cancerous tumours, as well as between normal colon tissues adjacent to tumours and normal colon tissue from healthy individuals. Finally, we harnessed these associations to develop a classifier using elastic net regression (with lasso and ridge regularisations) that predicts CRC diagnosis based on a patients sex and EAAs calculated from histologically normal controls (i.e. normal colon tissues adjacent to tumours and normal colon tissue from healthy individuals). The classifier demonstrated good diagnostic potential with ROC-AUC=0.886, which suggests that an EAA-based classifier trained on relevant data could become a tool to support diagnostic/prognostic decisions in CRC for clinical professionals. Our study also reemphasises the importance of open access clinical data for method development and training of young scientists. Obtaining the required approvals for controlled access data would not have been possible in the timeframe of this study.

genomics↗

The SRC-family kinase LYN inhibits tumour growth and activates inflammatory signalling pathways in an in vivo BRCA1 loss-of-function-associated mammary tumour model

LYN kinase is expressed in BRCA1 loss-of-function-dependent mouse mammary tumours, in the cells of origin of such tumours, and in human breast cancer. Suppressing LYN kinase activity in BRCA1-defective cell lines, as well as in in vitro cultures of Brca1-null mouse mammary tumours, is deleterious to their growth. Here, we have examined the interaction between LYN kinase and BRCA1 loss-of-function in an in vivo mouse mammary tumour model, using conditional knockout Brca1 and Lyn alleles. Comparison of Brca1 tumour cohorts showed little difference in mammary tumour formation between animals that were wild type, heterozygous or homozygous for the conditional Lyn allele, although this was confounded by factors including incomplete Lyn recombination in some tumours. RNAseq analysis demonstrated that tumours with high levels of Lyn gene expression had a slower doubling time, but this was not correlated with levels of LYN staining in tumour cells themselves. Rather, high Lyn expression and slower tumour growth were likely a result of B-cell infiltration. The multifaceted role of LYN means it is likely to present difficulties as a therapeutic target in breast cancer.

cancer biology↗

Hamsters are a model for COVID-19 alveolar regeneration mechanisms: an opportunity to understand post-acute sequelae of SARS-CoV-2

A relevant number of coronavirus disease 2019 (COVID-19) survivors suffers from post-acute sequelae of severe acute respiratory syndrome coronavirus 2 (PASC). Current evidence suggests a dysregulated alveolar regeneration in COVID-19 as a possible explanation for respiratory PASC symptoms, a phenomenon which deserves further investigation in a suitable animal model. This study investigates morphological, phenotypical and transcriptomic features of alveolar regeneration in SARS-CoV-2 infected Syrian golden hamsters. We demonstrate that CK8+ alveolar differentiation intermediate (ADI) cells occur following SARS-CoV-2-induced diffuse alveolar damage. A subset of ADI cells shows nuclear accumulation of TP53 at 6- and 14-days post infection (dpi), indicating a prolonged arrest in the ADI state. Transcriptome data show the expression of gene signatures driving ADI cell senescence, epithelial-mesenchymal transition, and angiogenesis. Moreover, we show that multipotent CK14+ airway basal cell progenitors migrate out of terminal bronchioles, aiding alveolar regeneration. At 14 dpi, presence of ADI cells, peribronchiolar proliferates, M2-type macrophages, and sub-pleural fibrosis is observed, indicating incomplete alveolar restoration. The results demonstrate that the hamster model reliably phenocopies indicators of a dysregulated alveolar regeneration of COVID-19 patients. The results provide important information on a translational COVID-19 model, which is crucial for its application in future research addressing pathomechanisms of PASC and in testing of prophylactic and therapeutic approaches for this syndrome.

pathology↗

FORGEdb: systematic analysis of candidate causal variants to uncover target genes and mechanisms in complex traits.

The majority of disease-associated variants identified through genome-wide association studies (GWAS) are located outside of protein-coding regions and are overrepresented in sequences that regulate gene expression. Prioritizing candidate regulatory variants and potential biological mechanisms for further functional experiments, such as genome editing, can be challenging, especially in regions with a high number of variants in strong linkage disequilibrium or multiple proximal gene targets. Improved annotation of the regulatory genome can help identify promising variants and target genes for functional genomics experiments. To advance this area, we developed FORGEdb (https://forge2.altiusinstitute.org/files/forgedb.html), a web-based tool that can rapidly integrate data for individual genetic variants, providing information on associated regulatory elements, transcription factor (TF) binding sites and target genes for over 37 million variants. FORGEdb uses annotations derived from data across a wide range of biological samples to delineate the regulatory context for each variant at the cell type level. Multiple data types, such as Combined Annotation Dependent Depletion (CADD) scores, expression quantitative trait loci (eQTLs), activity-by-contact (ABC) interactions, Contextual Analysis of TF Occupancy (CATO) scores, transcription factor (TF) motifs, DNase I hotspots, histone mark ChIP-seq peaks and chromatin states, are included in FORGEdb and these annotations are integrated into a FORGEdb score to guide assessment of functional importance. In summary, FORGEdb provides an expansive and unique resource of genomic annotations and an integrated score that can be used to accelerate the translation of identified genetic loci into biological insight.

genomics↗

Evaluation of epigenetic age acceleration scores and their associations with CVD related phenotypes in a population cohort

We evaluated associations between nine epigenetic age acceleration (EAA) scores and 18 cardio-metabolic phenotypes using an Eastern European ageing population cohort richly annotated for a diverse set of phenotypes (subsample, n = 306; aged 45-69 years). This was implemented by splitting the data into groups with positive and negative EAAs. We observed strong association between all epigenetic age acceleration scores and sex, suggesting that any analysis of EAAs should be adjusted by sex. We found that some sex-adjusted EAA scores were significantly associated with several phenotypes such as blood levels of gamma-glutamyl transferase and low-density lipoprotein, smoking status, annual alcohol consumption, multiple carotid plaques, and incident coronary heart disease status (not necessarily the same phenotypes for different EAAs). We demonstrated that even after adjusting EAAs for sex, EAA-phenotype associations remain sex-specific, which should be taken into account in any downstream analysis involving EAAs. The obtained results suggest that in some EAA-phenotype associations, negative EAA scores (i.e. epigenetic age below chronological age) indicated more harmful phenotype values, which is counter-intuitive. Among all considered epigenetic clocks, GrimAge was significantly associated with more phenotypes than any other EA scores in this Russian sample.

bioinformatics↗

Antibody-mediated depletion of human CLEC-2 in a novel humanised mouse model

Platelet C-type lectin-like receptor 2 (CLEC-2) has been proposed as a potential anti-thrombotic target as genetic or antibody-mediated receptor deficiency prevents occlusive thrombus formation in mice. This occurs through interaction with an unknown ligand as the endogenous ligand podoplanin is not present in the vasculature. However, the CLEC-2-podoplanin interaction does have an important role in tumour metastasis. There are currently no methods to test potential human therapeutics targeting CLEC-2, such as antibodies, in vivo. We have therefore generated and characterised a humanised CLEC-2 mouse (hCLEC-2KI) and developed a novel monoclonal anti-human CLEC-2 antibody, HEL1, for in vivo testing. hCLEC-2KI mice were phenotypically normal and had comparable platelet glycoprotein receptor expression, activation and aggregation to wildtype platelets. hCLEC-2KI mice had both comparable bleeding and vessel occlusion times to WT mice. Challenging hCLEC-2KI mice with HEL1 or a second monoclonal anti-hCLEC-2 antibody, AYP1, resulted in transient thrombocytopenia as well as CLEC-2 depletion for more than 2 weeks but had no effect on haemostasis. This illustrates the power of the humanised CLEC-2 mouse model in evaluating novel therapeutics in vivo, including antibodies that target CLEC-2, as well as the limited effect on haemostasis when targeting CLEC-2.

physiology↗

Progression and Resolution of SARS-1 CoV-2 Infection in Golden Syrian Hamsters

To catalyze SARS-CoV-2 research including development of novel interventive and preventive strategies, we characterized progression of disease in depth in a robust COVID-19 animal model. In this model, male and female golden Syrian hamsters were inoculated intranasally with SARS-CoV-2 USA-WA1/2020. Groups of inoculated and mock-inoculated uninfected control animals were euthanized at day 2, 4, 7, 14, and 28 days post-inoculation to track multiple clinical, pathology, virology, and immunology outcomes. SARS-CoV-2-inoculated animals consistently lost body weight during the first week of infection, had higher lung weights at terminal timepoints, and developed lung consolidation per histopathology and quantitative image analysis measurements. High levels of infectious virus and viral RNA were reliably present in the respiratory tract at days 2 and 4 post-inoculation, corresponding with widespread necrosis and inflammation. At day 7, when infectious virus was rare, interstitial and alveolar macrophage infiltrates and marked reparative epithelial responses (type II hyperplasia) dominated in the lung. These lesions resolved over time, with only residual epithelial repair evident by day 28 post-inoculation. The use of quantitative approaches to measure cellular and morphologic alterations in the lung provides valuable outcome measures for developing therapeutic and preventive interventions for COVID-19 using the hamster COVID-19 model.

pathology↗