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Garcia, E.

Publications and source records attributed to Garcia, E..

At least 19 recordsLinked to original sources

Multi-Site Reproducibility Study of 3D High-Content Analysis with Dual-View Oblique Plane Microscopy

High content imaging is being applied to achieve quantitative fluorescence readouts in increasingly complex 3-dimensional (3D) cell culture models such as spheroids and organoids. Compared to conventional 2D assays, 3D assays better represent biological heterogeneity but require more complex sample preparation, 3D imaging and 3D image analysis that can affect the accuracy and precision of such assays. We used spheroids formed from the NRAS-activated melanoma cell line 19161 modified to express an ERK kinase translocation reporter (KTR) as an exemplar 3D phenotypic assay carried out in 96-well plates. The spheroids were treated with the ERK activator TPA and a range of concentrations of the MEK inhibitor Binimetinib. 3D live-cell imaging with sub-cellular spatial resolution was performed using a dual-view oblique plane microscope (dOPM) - a form of single-objective light-sheet microscope - and the experiment was performed separately at 4 different institutes. The results were analysed using an identical 3D analysis pipeline and parameters. We assessed the variation in assay readout using a linear mixed effects model. Random variance at the well level was negligible (SD = 0.0048 relative to range of KTR biosensor readout at reference site of 0.17), indicating low technical noise. Treatment effects were dose-dependent and highly statistically significant compared to DMSO control across all sites (Dunnett-corrected p < 0.001). The range in KTR readout between the minimum (3.5 M Binimetinib) and maximum (100 nM TPA) treatments varied between 59 to 96% relative to the reference site. Measured bias in KTR readout between sites was between 6 and 12% of the range of the reference site. This study quantifies the reproducibility of a 3D live spheroid-based assay employing a fluorescence biosensor requiring readout out at the per-cell level using the dOPM platform and discusses areas where experimental protocol could be improved in the future to further improve reproducibility.

bioengineering↗

Phylogenetic Analysis and Structural Evaluation of Staphylococcus aureus Serine-Aspartate Repeat-Containing Protein D with a Focus on Periprosthetic Joint Infection

Serine-aspartate repeat-containing protein D (SdrD) is a Staphylococcus aureus cell wall-anchored, calcium-binding adhesin member of the MSCRAMM Sdr subfamily that may contribute to bacterial adhesion and virulence. S. aureus is the most common cause of periprosthetic joint infection (PJI). Population-level distribution and sequence diversity of SdrD among clinical PJI isolates have not been systematically characterized, and the SdrD binding mechanism is still not well understood. To address these gaps, sdrD alleles were queried across 156 newly sequenced PJI isolates and compared to publicly available S. aureus genomes, and nucleotide- and protein-level phylogenies of the sdrCDE locus constructed. The SdrD crystal structure from S. aureus JH1 was determined, with solution small-angle X-ray scattering (SAXS) and molecular dynamics (MD) simulations, and assessment of conformational changes with calcium depletion. Three dominant sdrD subtypes were defined, associating with USA300, JH1, and TCH60; the JH1 sdrD subtype was predominant among PJI isolates. Structural studies showed that the conformation of individual domains and interdomain organization of the multidomain SdrD have limited flexibility in solution, and that the calcium-binding B domain retains its core fold under conditions of calcium depletion. Together, the findings presented support functional diversification among Sdr family members in mediating host attachment and inform a re-evaluation of the ligand-binding mechanism previously proposed for SdrD. AUTHOR SUMMARYStaphylococcus aureus is the leading cause of infections that develop around joint implants (periprosthetic joint infection, PJI). This bacterium has a large arsenal of surface proteins that allow it to stick to human tissues and implanted devices. This work focused on one such protein, SdrD, which has been linked to implant-associated infections but the structure and diversity of which among patients with PJI had not been well characterized. The genetic sequences of SdrD were analyzed across thousands of bacterial genomes, including those from patients with PJI. Distinct genetic variants of the protein were found, one of which was particularly common with PJI. The three-dimensional structure of SdrD was determined at atomic resolution and solution small-angle X-ray scattering (SAXS) and molecular dynamics used to study how it moves and responds to changes in its environment. Contrary to what was previously described, SdrD was shown to be relatively rigid. These findings change how SdrDs mechanism of action should be considered, potentially informing design strategies to block bacterial attachment before infection takes hold.

biophysics↗

Quantitative evaluation of LED based optical autofocus module

We report an improved version of the open-source optical autofocus module ("openAF") for light microscopy using a light emitting diode (LED), together with a method to independently quantify the performance of optical autofocus systems using 2D autocorrelation analysis of astigmatic imaging of fluorescent nanobeads. We apply the latter for both the LED-based and the previous super luminescent diode (SLD) based implementations of the openAF optical autofocus approach used in conjunction with a 100x 1.4 NA oil-immersion objective lens. The new approach accounts for power variations in the autofocus light source and we demonstrate that the convenient LED-based system can provide axial stability with a standard deviation <10 nm over at least 45 minutes when switched on from cold, during which the LED power varies as it reaches thermal equilibrium.

bioengineering↗

Heterologous betacoronavirus spike immunization in nonhuman primates elicits cross-reactive antibodies that neutralize both sarbeco- and merbecoviruses

In anticipation of future coronavirus (CoV) pandemics, developing vaccines that elicit broadly neutralizing antibodies (bnAbs) against diverse CoVs is critical. Here, we vaccinated rhesus macaques with SARS-CoV-2 spike (S)-protein, then boosted with heterologous {beta}-CoV S-proteins to focus responses to common conserved S2 bnAb epitopes. Initial SARS-CoV-2 priming elicited receptor-binding domain (RBD)-focused responses, while MERS-CoV boosting redirected responses toward the S2 region, including the stem-helix bnAb site. Although S2-directed serum cross-neutralization was undetectable and most isolated cross-reactive monoclonal antibodies (mAbs) targeted non-neutralizing epitopes, two S2 stem-helix mAbs were identified from memory B cells. These bnAbs neutralized diverse sarbeco- and merbecoviruses, including MERS-CoV, and conferred robust in vivo protection against SARS-CoV-2 challenge. Structural studies revealed that these macaque bnAbs closely mimic human S2-stem bnAbs induced by infection. These findings provide proof-of-principle for vaccination strategies that elicit broadly protective {beta}-coronavirus responses and highlight non-human primates as a translational model for evaluating S2-targeted immunogens.

immunology↗

Functional Profiling of Kiwifruit Phyllosphere Bacteria: Copper Resistance and Biocontrol Potential as a Foundation for Microbiome-Informed Strategies

Bacterial canker, caused by Pseudomonas syringae pv. actinidiae (Psa) is a major threat to global kiwifruit production. Copper-based bactericides remain widely used, but increasing resistance underscores the need for alternative strategies. Understanding the functional capabilities of phyllosphere bacteria under copper pressure is critical for designing sustainable alternatives. This study provides a culture-based functional inventory of bacteria associated with Actinidia chinensis var. deliciosa leaves from Portuguese orchards under long-term copper management, aiming to identify native taxa with traits relevant to plant health and resilience. A total of 1,058 isolates were recovered and grouped into 261 RAPD clusters, representing 58 species across 29 genera. Representative strains were screened for plant growth-promoting (PGP) traits (IAA, siderophore production, phosphate solubilization, ammonia production), copper tolerance, and in vitro antagonism against Psa. Copper resistance was widespread (53.3% of isolates with MIC [&ge;]0.8 mM), including the first evidence of a highly copper-resistant PSA in Portuguese kiwifruit orchards and an exceptionally resistant non-pathogenic strain (Erwinia iniecta, MIC 2.8 mM). A subset of 25 isolates combined all PGP traits. In parallel, several isolates exhibited antagonism against Psa, including Bacillus pumilus, which consistently inhibited pathogen growth. Notably, some antagonistic isolates overlapped with the multifunctional PGP subset, highlighting promising candidates for integrated biocontrol strategies. These findings reveal the kiwifruit phyllosphere as a reservoir of functionally diverse and copper-resilient bacteria, highlighting both ecological risks and opportunities for microbiome-based biocontrol innovation. This work establishes a functional baseline for future in planta validation and microbiome-informed disease management strategies.

microbiology↗

Salmonids reveal principles of regulatory evolution following autotetraploidization

Early vertebrate autotetraploidization events may have enabled major innovations by expanding the genetic material for functional diversification, yet their ancient timing obscures how genome doubling reshaped gene regulatory evolution. Salmonids provide a unique window to these mechanisms, because they experienced a comparatively recent autotetraploidization and are earlier in the rediploidization process - which creates new genes and regulatory elements during evolution. Here, using large-scale multiomics spanning embryonic and adult tissues in two salmonids, we investigate gene regulatory evolution following genome doubling and rediploidization, which we show is governed by developmental and tissue-specific context, with a period of maximal constraint at advanced stages of embryogenesis. This work advances understanding of vertebrate genome evolution, while providing an open resource supporting salmonid aquaculture and conservation.

evolutionary biology↗

Functional Characterization of 123 Genes from Mycobacteriophage LeBron Uncovers Cytotoxic Gene Families in Cluster L1

Bacteriophages represent a vast reservoir of genetic diversity however, functional annotation remains a major challenge, as most predicted gene products lack detectable similarity to characterized gene families. Experimental approaches such as systematic overexpression screens provide an avenue for identifying phage genes that influence bacterial physiology. Here, we report an overexpression screen of all 123 predicted protein-coding genes from Cluster L1 mycobacteriophage LeBron, the first representative of this cluster to undergo genome-wide functional analysis. Expression assays in Mycobacterium smegmatis revealed that 39 genes (32%) impaired host growth, with nineteen of these toxic genes (49%) assigned no known function. The proportion of cytotoxic genes observed in LeBron is comparable to findings from Clusters K and F, despite minimal sequence conservation across clusters. Interestingly, a subset of LeBrons toxic genes appear to be functionally analogous to previously identified toxic genes in other clusters, suggesting conserved biological activities carried out by non-homologous proteins. Additionally, this analysis uncovered several novel gene families that elicit strong cytotoxic effects, expanding the known catalog of phage-derived bacterial growth inhibitors. These results provide new insights into phage gene functions and demonstrate the value of genome-wide expression screening for uncovering conserved and cluster-specific interactions between bacteriophages and their hosts.

microbiology↗

Dual-targeting snRNA gene therapy rescues STMN2 and UNC13A splicing in TDP-43 proteinopathies

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder caused by the selective deterioration of motor neurons in the central nervous system (CNS). A key driver of this pathogenesis is nuclear loss of ALS-associated protein TDP-43, leading to mis-splicing of TDP-43 targets including important neuronal genes STMN2 and UNC13A. Here, we have developed a gene therapy strategy for ALS and related TDP-43 proteinopathies, to correct mis-splicing of both STMN2 and UNC13A cryptic exons using small nuclear RNAs (snRNAs) encoded from a single vector. We identified promoter sequence elements to increase therapeutic snRNA expression by 10-fold, then further optimized the expression cassette with combinatorial snRNA targeting to rescue multiple cryptic splicing targets. The engineered snRNAs restored normal pre-mRNA processing of both STMN2 and UNC13A transcripts despite TDP-43 loss of function, rescuing stathmin-2 protein levels in iPSC derived motor neurons, restoring their axonal regeneration capacity to wild-type levels. In addition, adeno-associated virus (AAV) delivery of the snRNAs to the murine central nervous system in the constitutive cryptic splicing model Stmn2Hum{Delta}GU fully restored cortical Stmn2 pre-mRNA processing, highlighting the utility of snRNAs as a therapeutic modality in vivo. Together, this study demonstrates that snRNAs are a promising and versatile therapeutic strategy for the simultaneous correction of multiple aberrant transcripts affected by cryptic splicing in TDP-43 proteinopathies.

neuroscience↗

Video-Based Cattle Behavior Detection for Digital Twin Development in Precision Dairy Systems

Digital twins in dairy systems require reliable behavioral inputs. We develop a video-based framework that detects and tracks individual cows and classifies seven behaviors under commercial barn conditions. From 4,964 annotated clips, expanded to 9,600 through targeted augmentation, we couple YOLOv11 detection with ByteTrack for identity persistence and evaluate SlowFast versus TimeSformer for behavior recognition. TimeSformer achieved 85.0% overall accuracy (macro-F1 0.84) and real-time throughput of 22.6 fps on RTX A100 hardware. Attention visualizations concentrated on anatomically relevant regions (head/muzzle for feeding and drinking; torso/limbs for postures), supporting biological interpretability. Structured outputs (cow ID, start-end times, durations, confidence) enable downstream use in nutritional modeling and 3D digital-twin visualization. The pipeline delivers continuous, per-animal activity streams suitable for individualized nutrition, predictive health, and automated management, providing a practical behavioral layer for scalable dairy digital twins.

animal behavior and cognition↗

Anthropocene genetic diversity loss in the marine tropics

Genetic diversity is a crucial component of biodiversity, and as such, its maintenance and preservation is of high conservation concern. Tropical environments are undergoing intense rates of environmental change, and these changes may be driving large declines in genetic diversity. However, data on genetic diversity are highly skewed towards temperate regions. The degree to which diversity loss has occurred in tropical species, particularly marine species, remains an open and important question. Here, we directly compare genomic data from modern and museum collections of two commercially-harvested nearshore marine fishes (Equulites laterofenestra and Gazza minuta) gathered from a single location in the Philippines, spanning a century of intense environmental change. These data reveal a marked loss in genetic diversity and evidence for multiple orders of magnitude reductions in effective population size (Ne) in both species, indicating substantial genomic erosion. Such a decline highlights the long-lasting genomic consequences of anthropogenic activity and sheds light on an, until-now, invisible loss of diversity from the most biodiverse ocean region. Significance StatementRecent reports have shown that genetic diversity in marine fishes has declined either slightly or not at all during the Anthropocene. However, almost all studies investigating marine genetic diversity loss have been from temperate latitudes, whereas tropical marine environments experience some of the most intense human impacts. Here, we directly compare genomic data from modern and historical specimens of two commercially-harvested fishes from the Philippines. We show that marine species in the tropics have already lost substantial genetic diversity and may have undergone severe bottlenecks over the past century. These results shine a light on the previously invisible loss of genetic diversity in the most biodiverse region of the ocean, and they emphasize the evolutionary consequences of the Anthropocene.

ecology↗

CDK4/6 Inhibition Uncovers Subtype-Specific Vulnerabilities and Immune-Related Responses in Esophageal Squamous Cell Carcinoma.

Esophageal squamous cell carcinoma (eSCC) is a highly aggressive malignancy with poor prognosis and limited therapeutic options. Although immune checkpoint inhibitors such as nivolumab, have shown clinical benefit, particularly in patients with high PD-L1 expression, this subgroup represents only a small fraction of eSCC cases. CDK4/6 inhibitors such as palbociclib have only been tested as second-line agents in eSCC, often in combination with EGFR inhibitors, with minimal benefit. Our study evaluates palbociclib as a first-line therapy in treatment-naive eSCC models. Using a panel of 22 eSCC cell lines with integrated multi-omics and phenotypic assays, we identified three response subtypes, resistant, delayed and arrested, correlated to Rb-pathway status. Interestingly, in delayed responders, palbociclib induced replication stress, DNA damage, and unprotected micronuclei enriched for cGAS, triggering activation of interferon-stimulated genes. Consistent with this, palbociclib enhanced immune cell infiltration in delayed eSCC spheroids within a preclinical vascularized 3D microfluidic system. Our study demonstrates that first-line palbociclib treatment unmasks intrinsic vulnerabilities in the CDK4/6-Rb axis and triggers innate immune activation in molecularly defined eSCC. Using a translationally relevant 3D vascularized microfluidic system, we provide evidence that early CDK4/6 inhibition not only stall cancer cell growth but also promotes immune cells recruitment. In conclusion, our study identifies palbociclib as a viable first-line therapeutic candidate in selected eSCC patients and uncover its immunomodulatory potential. SignificanceThese findings support further research into CDK4/6 inhibition as first-line treatment for eSCC and highlight its potential to influence the tumor immune microenvironment in ways that could improve responses to combination therapies.

cancer biology↗

A Mechanism Based Pharmacokinetic/Pharmacodynamic Analysis of Polymyxin B-Based Combination Therapy Against Carbapenem-Resistant Klebsiella pneumoniae Isolates with Diverse Phenotypic and Genotypic Resistance Mechanisms

Increased resistance to {beta}-lactams/{beta}-lactamase inhibitor by mutations in {beta}-lactamases gene, porin mutations and efflux pumps complicates the management of carbapenem-resistant Klebsiella pneumoniae (CRKP). Polymyxin B (PMB) based combination therapy is considered as a best alternative treatment for those middle and low-income countries that cannot access to the latest medicines. Its crucial to know both phenotypic and genotypic characteristics of a pathogen to understand the killing effect of each drug and its combinations. Hence, our objective of this study was to incorporate mechanistic insights gained from resistance mechanisms to develop a mechanism based pharmacokinetic/pharmacodynamic model (MBM). Six clinical CRKP isolates were used for static concentration time kill (SCTK) assays to evaluate the rate and extent of killing by monotherapy, double and triple combinations using PMB, meropenem and fosfomycin. A MBM was developed using the SCTK data in S-ADAPT. The MBM estimated lower maximum killing rate constant of PMB (3.61 h-{superscript 1}) in an isolate with non-functional MgrB and high-level phenotypic resistance. Based upon model discrimination and PMBs outer membrane disruption, mechanistic synergy was included in 3 isolates which has porin mutations. Mechanistic synergy of PMB was 83-88% with meropenem and 81-98% with fosfomycin. The PMB concentration required to achieve 50% of synergy was 0.48-0.64 mg/L. Simulations with a lower PMB regimen (1mg/kg q12h) and fosfomycin (8g q8h) showed >73% reduction in area under the bacterial load-versus-time curve for four isolates. The triple combination showed 67.7% reduction in non-carbapenamase producing isolate. This study demonstrates that a low dosing regimen of PMB can produce synergistic effects in combination therapy and might be effective in managing infections caused by CRKP, including PMB resistant isolates. Author summaryAntimicrobial resistance is a major concern in treating infectious diseases. CRKP bacterial isolates are resistant to most of the novel antimicrobial agents. One of the primary resistant mechanisms is restricting the permeability of drugs to the site of action. Polymyxin B, an antimicrobial agent, disrupts the bacterial outer membrane, enhancing the permeability of other drugs. When using combination therapy with polymyxin B, selecting drugs with different mechanisms of action is crucial to enhance synergistic effects and improve treatment efficacy. In our study we chose to evaluate the efficacy of meropenem and fosfomycin in double and triple combination therapies. Mechanism based models (MBMs) are the strongest tool to analyse the time course bacterial load data. Our study provides insights into applying available phenotypic and genotypic information to refine and enhance the accuracy of MBMs. Final model simulations revealed that low exposure of polymyxin B below the nephrotoxic threshold was sufficient to produce synergistic effects when combined with fosfomycin and meropenem. Additionally, we found that polymyxin B combination with fosfomycin was more effective compared to meropenem in treating CRKP.

pharmacology and toxicology↗

Metagenomes and Metagenome-Assembled Genomes from Tidal Lagoons at a New York City Waterfront Park

We report the sequencing and analysis of 15 shotgun metagenomes, including the reconstruction of 129 high-quality metagenome-assembled genomes, from tidal lagoons and bay water at Bush Terminal Piers Park in Brooklyn, NY sampled from July to September 2024.. Our metagenomic database for this site provides an important baseline for ongoing studies of the microbial communities of public parks and waterfront areas. In particular, we provide rich functional and taxonomic annotations that enable the use of these metagenomes and metagenome-assembled genomes for a wide variety of downstream applications.

microbiology↗

Spatiotemporal Analysis of Remyelination Reveals a Concerted Interferon-Responsive Glial State That Coordinates Immune Infiltration

Remyelination, the process by which axons are re-encased in myelin after injury, is a critical step in restoring brain function, yet the dynamics from initial injury to repair remain poorly characterized. Here, we combined optimized single-nucleus RNA-seq with Slide-seqv2, a high-resolution spatial transcriptomics technology, to densely reconstruct the cellular processes that coordinate remyelination after a focal demyelinating injury. This revealed several findings: First, we found extensive transcriptional diversity of glia and monocyte-derived macrophages from demyelination to repair. Second, we identified a population of infiltrating peripheral lymphocytes--predominantly CD8 T-cells and natural killer cells--that are enriched specifically during remyelination. Third, we identified a concerted interferon-response gene signature that is shared across several cell types--microglia, astrocytes, and the oligodendrocyte lineage--just prior to reestablishment of myelin. These interferon-responsive glia (IRG) form clusters around remyelinating white matter and their formation is solely dependent on the type I interferon receptor. Functionally, we found that IRG secrete the cytokine CXCL10 which mediates infiltration of peripheral lymphocytes into the repairing white matter. Depletion of the most abundant infiltrating lymphocyte, CD8 T-cells, attenuated the differentiation of mature oligodendrocytes during remyelination. Together, our data reveals the diversity of glial-immune interactions that orchestrate white matter repair and a type I-dependent glial state that drives lymphocyte influx into damaged white matter to modulate oligodendrocyte differentiation. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=57 SRC="FIGDIR/small/649486v1_ufig1.gif" ALT="Figure 1"> View larger version (27K): org.highwire.dtl.DTLVardef@2c7e07org.highwire.dtl.DTLVardef@1063719org.highwire.dtl.DTLVardef@10b8862org.highwire.dtl.DTLVardef@26dd8b_HPS_FORMAT_FIGEXP M_FIG C_FIG

neuroscience↗

OCT4 Negatively Regulates the Transcriptional Programming of the Early Region 3 Immune Evasion Genes of Human Adenovirus

Genomes of viruses are constrained by the virions nanoscale, and viral nucleotide sequences without function are a luxury. Yet the double-stranded DNA genome of human adenovirus (HAdV) contains large regions without known purpose. Using TRANSFAC and ChIP-Seq analysis, we identified binding of OCT4 (octomer-binding transcription factor 4) to a noncoding region of HAdV-D37 DNA. Manipulation of OCT4 expression impacted viral E3 gene transcription and gp19k protein expression, altering subsequent MHC Class I expression. These effects were specific to OCT4 binding to the adenovirus 5' inverted terminal repeat (ITR) within nucleotides 101-159. Using targeted mutations to OCT4, we found one of two OCT4 binding motifs in the ITR to be crucial for repression of E3 gene expression. In OCT4-siRNA treated cells, E3 RID- gene expression was also upregulated to inhibit pro-apoptotic signals, suggesting that OCT4 binding also indirectly represses viral replication. Consistent with a role for transcription factors in epigenetic modification during infections, OCT4 knockdown also reduced histone H3 acetylation and DNA methylation. In stem cells, OCT4 sustains pluripotency, whereas in somatic cells, OCT4 plays a dispensable role in self-renewal and maintenance. Herein, we show that OCT4 binding also confers a previously unidentified function to non-coding adenovirus DNA. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=124 SRC="FIGDIR/small/650321v1_ufig1.gif" ALT="Figure 1"> View larger version (23K): org.highwire.dtl.DTLVardef@1a94a11org.highwire.dtl.DTLVardef@13dc8e5org.highwire.dtl.DTLVardef@1505f22org.highwire.dtl.DTLVardef@195be29_HPS_FORMAT_FIGEXP M_FIG C_FIG

cell biology↗

VP-CLEM-Kit: An accessible pipeline for visual proteomics using super resolution volume correlative light and electron microscopy (SR-vCLEM)

Visual proteomics (VP) aims to allow researchers to visualise, measure and analyse proteins in the context of cell and tissue structure in health and disease. VP is becoming a reality through technological advances across several domains, including in situ structural biology and correlative light and electron microscopy (CLEM). However, widespread adoption remains limited due to the complexity and cost of the various VP approaches reported to date. Here we present the VP-CLEM-Kit, a disruptive cost-effective pipeline for super resolution volume CLEM (SR-vCLEM) that can be implemented with minimal advanced electron microscopy expertise and equipment, making it accessible to light microscopy facilities and research labs. SR-vCLEM is based on in-resin fluorescence (IRF), where fluorophores are preserved through processing into resin. The easyIRF protocol reported here reduces the requirement for complex costly sample preparation equipment and toxic chemicals compared to standard IRF protocols. easyIRF blocks are cut into ultrathin sections that are imaged using tomoSTORM, a new modular and cost-effective openFrame-based light microscope controlled by the open-source software package Micro-Manager that provides serial single molecule localisation microscopy in array tomography format. Sections are then post-stained and imaged using a tabletop scanning electron microscope controlled by open-source SBEMimage software to run in array tomography format. We demonstrate the potential of the VP-CLEM-Kit by imaging organelle reporters in human cell lines and stem cell derived neurons, fluorescently labelled protein in neurons, and immunolabelled cells in human kidney biopsy tissue from transplant patients. The VP-CLEM-Kit delivers a [~]5-fold improvement in resolution at a [~]7-fold lower cost, and thus provides new technical capability as well as a blueprint for more equitable access to advanced imaging workflows.

cell biology↗

Urban crops demonstrate comparable potential for organic carbon storage as natural ecosystems.

Urban greenspaces, encompassing parks, golf courses, roundabouts, and urban crops, have potential to offset urban carbon footprints by storing soil organic carbon (SOC). This study analyzed particulate organic carbon (POC) and mineral-associated organic carbon (MAOC) stocks in topsoil across 27 Iberian cities, comparing urban greenspaces with natural ecosystems under varying climatic and edaphic conditions. Results revealed that urban greenspaces store comparable SOC stocks to natural ecosystems, with MAOC stocks being more dominant and stable across land-use types. POC stocks showed variability, particularly lower in roundabouts and parks compared to natural ecosystems, but remained similar in golf courses and urban crops. SOC fractions correlated inversely with mean annual temperature (MAT), emphasizing the need for cooling strategies in urban areas to preserve stable carbon pools. While MAOC exhibited saturation at higher SOC levels, POC showed a linear increase. This study highlights the importance of tailored management practices to enhance carbon storage in urban soils for climate change mitigation.

biochemistry↗

Virus and Cell Specific HMGB1 Secretion and Subepithelial Infiltrate Formation in Adenovirus Keratitis

A highly contagious infection caused by human adenovirus species D (HAdV-D), epidemic keratoconjunctivitis (EKC) results in corneal subepithelial infiltration (SEI) by leukocytes, the hallmark of the infection. To date, the pathogenesis of corneal SEI formation in EKC is unresolved. HMGB1 (high-mobility group box 1 protein) is an alarmin expressed in response to infection and a marker of sepsis. Earlier studies using a different adenovirus species, HAdV-C, showed retention of HMGB1 in the infected cell nucleus by adenovirus protein VII, enabling immune evasion. Here, using HAdV-D we show cell-specific HMGB1 secretion by infected cells, and provide an HAdV-D specific mechanism for SEI formation in EKC. HMGB1 was secreted only upon infection of human corneal epithelial cells, not from other cell types, and only upon infection by HAdV-D types associated with EKC. Acetylated HMGB1 translocation from the nucleus to the cytoplasm, then to the extracellular milieu, was tightly controlled by CRM1 and LAMP1, respectively. Primary stromal cells when stimulated by rHMGB1 expressed proinflammatory chemokines. In a novel 3D culture system in tune with the architecture of the cornea, HMGB1 released by infected corneal epithelial cells induced leukocytic infiltrates either directly and/or indirectly via stimulated stromal cells, which together explains SEI formation in EKC.

microbiology↗