Biology subjects

Perry, D.

Publications and source records attributed to Perry, D..

10 recordsLinked to original sources

bioRxiv2026

An Aging Risk-Factor Scale: Biomarkers of Renal Disease and Anemia are Primary Predictors of Three-Year Survival in Common Marmosets (Callithrix jacchus)

Valid animal models are needed to evaluate how age-related changes in kidney function influence healthspan. Aging marmosets frequently develop renal insufficiency with anemia and exhibit reductions in body mass and metabolic rate. However, it remains unclear which age-related changes predict survival and which thresholds indicate increased mortality risk. We prospectively evaluated age, body composition, resting energy expenditure, hematology, and blood chemistry as predictors of 3-year survival in female and male marmosets (n = 66), 2-16 years of age. Objectives were to identify prognostic markers, define high-risk thresholds, and to develop and test a composite risk-factor scale for mortality screening in captivity. A 10-variable model showed the best predictive performance in multivariable Cox proportional hazards modeling, and was retained for further analysis (concordance = 0.881, p < 0.001). ROC curves using Youdens Index and AUC identified high-risk thresholds for predictors in the multivariable model, and threshold-defined categories were evaluated by Kaplan-Meier survival analysis. The 10 binary risk-factors were combined into a composite scale scored from 0 to 10 and tested with Cox regression. The scale explained approximately 42% of variance in survival and each additional risk factor increased mortality risk 1.75-fold (95% CI: 1.43-2.14, p < 0.001). Marmosets with [≥]7 risk factors exhibited a 19-month reduction in survival, and this high-risk threshold predicted 3-year survival with 89.4% accuracy. Results support the scale as a screening tool for mortality risk and highlight the high prevalence of age-associated renal disease and anemia in marmosets.

physiology↗

bioRxiv2025

Environmental and Maternal Imprints on Infant Gut Metabolic Programming

Early life is a critical period for immune and metabolic programming, but developmental patterns remain underexplored in populations from low- and middle-income countries. Here, we profiled the microbiome and metabolome of 55 Bangladeshi mother-infant dyads over the first six months of life. Importantly, we observed an increase in microbially-derived bile amidates and N-acyl lipids with age in conjunction with reads matching the bile salt hydrolase/transferase (bsh) gene. While microbial source tracking confirmed maternal fecal seeding, a substantial environmental contribution was also highlighted. Differences in infant fecal metabolic profiles were associated with delivery mode, maternal milk composition, household assets, and household-level water treatment. C-section delivery and untreated drinking water were linked to transient metabolic differences, including increases in bile amidates, N-acyl lipids, and other host-microbe co-metabolic products, including acylcarnitines. Multi-omics analysis revealed specific microbial-metabolite relationships, highlighting how early environmental and maternal living circumstances shape metabolic gut programming through the microbiome.

microbiology↗

bioRxiv2024

Effects of longitudinal bending stiffness and midsole foam on running energetics

BackgroundAdvanced footwear technology has become commonplace in the competitive running world. However, a systematic exploration of the effects of each of the primary components has not yet been presented. PurposeTo quantify running economy and step parameters in four different shoe conditions: PEBA shoes with plate, PEBA shoes without plate, EVA shoes with plate and EVA shoes without plate. MethodsParticipants ran at 14 km/h (n = 8 males) or 12 km/h (n = 6 females) on a treadmill. The shoe order was randomly assigned for the four shoe conditions, where the participants wore each shoe twice in a mirrored order. ResultsThere was a significant reduction in metabolic power (1.0%) associated with the presence of a plate, as well as a similar reduction based on foam type (1.0%). However, there was no significant interaction between presence of plate and foam type. Adding a plate significantly reduced metabolic power for EVA by 1.3% but not for PEBA. PEBA foam significantly reduced metabolic power by 1.3% in shoes without a plate, but not for the shoes with a plate. Step frequency and contact time were similar between shoes and not correlated to running economy improvements. ConclusionsStarting from a baseline condition with traditional foam without a plate, either adding a plate or using PEBA foam improved running economy with a similar amount (1.3%). Adding the alternate second feature non-significantly improved running economy with an additional 0.6%. The benefit of both technologies combined (1.9%) was smaller than the sum of its parts (1.3% each). Key pointsO_LIThe use of a PEBA foam midsole or the addition of a carbon fiber plate improves running economy a similar amount when compared to a traditional EVA running shoe without a plate. C_LIO_LIContrary to our hypothesis, the benefit of both technologies combined (1.9%) was smaller than the sum of its parts (1.3% each). C_LI

physiology↗

bioRxiv2024

Application of Cancer Cell Line Encyclopedia for Measuring Correlation Between Transcriptomics and Proteomics as a Guide for System-level Insights

Robust and reliable proteome measurements provide mechanistic insights in biomedical research. SOMAmer (Slow Off-rate Modified Aptamer) reagents are modified, DNA-based, affinity reagents that measure defined target proteins with reproducibility and accuracy similar to monoclonal antibodies. Applying SOMAmer reagent technology, we developed SomaScan, a clinical proteome profiling platform with capability to measure 7,523 proteoforms for 6,594 human proteins by UniprotID in small sample volumes (e.g., 55l plasma or serum). We evaluated the platform by profiling the proteome of a panel of well characterized Cell Line Encyclopedia (CCLE) cancer models. Unsupervised machine learning analyses demonstrate the SomaScan assay distinguishing cell lines on the basis of their proteome signatures, and identifying both tissue-specific and oncogenic pathways. The proteome measured by SomaScan correlates with published CCLE transcriptome at a level comparable to other published transcript to proteome studies. Taken together, we demonstrate that the SomaScan platform is a technically reproducible system suitable for biomedical and clinical applications that reliably illuminates underlying biomolecular mechanisms.

systems biology↗

bioRxiv2023

Human immune phenotyping reveals accelerated aging in type 1 diabetes

The composition of immune cells in peripheral blood is dramatically remodeled throughout the human lifespan, as environmental exposures shape the proportion and phenotype of cellular subsets. These dynamic shifts complicate efforts to identify disease-associated immune signatures in type 1 diabetes (T1D), which is variable in age of onset and rate of {beta}-cell decline. Herein, we conducted standardized flow cytometric immune profiling on peripheral blood from a cross-sectional cohort of T1D participants (n=240), their first-degree relatives (REL, n=310), those at increased risk with two or more islet autoantibodies (RSK, n=24), and autoantibody negative healthy controls (CTR, n=252). We constructed an immune-age predictive model in healthy subjects and developed an interactive data visualization portal (ImmScape; https://ufdiabetes.shinyapps.io/ImmScape/). When applied to the T1D cohort, this model revealed accelerated immune aging (p<0.001) as well as phenotypic signatures of disease after age correction. Of 192 investigated flow cytometry and complete blood count readouts, 46 were significantly associated with age only, 25 with T1D only, and 23 with both age and T1D. Phenotypes associated with T1D after age-correction were predictive of T1D status (AUROC=82.3%). Phenotypes associated with accelerated aging in T1D included increased CXCR3+ and PD-1+ frequencies in naive and memory T cell subsets, despite reduced PD-1 expression levels (mean fluorescence intensity) on memory T cells. Additionally, quantitative trait locus analysis linked an increase in HLA-DR expression on monocytes with the T1D-associated HLA-DR4/DQ8 genotype, regardless of clinical group. Our findings demonstrate advanced immune aging in T1D and highlight disease-associated phenotypes for biomarker monitoring and therapeutic interventions. One Sentence SummaryPeripheral blood characterization reveals accelerated immune-age and age-adjusted proinflammatory immune phenotypes in type 1 diabetes.

immunology↗

bioRxiv2022

Dysregulated nuclear export of the late herpes simplex virus 1 transcriptome through the vhs-VP22 axis uncouples virus cytopathic effect and virus production

Herpes simplex virus 1 (HSV1) expresses its genes in a classical cascade culminating in the production of large amounts of structural proteins to facilitate virus assembly. HSV1 lacking the virus protein VP22 ({Delta}22) exhibits late translational shutoff, a phenotype that has been attributed to the unrestrained activity of the virion host shutoff (vhs) protein, a virus-encoded endoribonuclease which induces mRNA degradation during infection. We have previously shown that vhs is also involved in regulating the nuclear-cytoplasmic compartmentalisation of the virus transcriptome, and in the absence of VP22 many virus transcripts are sequestered in the nucleus late in infection. Here we show that despite expressing minimal amounts of structural proteins and failing to plaque on human fibroblasts, the strain 17 {Delta}22 virus replicates and spreads as efficiently as Wt virus, but without causing cytopathic effect (CPE). Nonetheless, CPE-causing virus spontaneously appeared on {Delta}22-infected human fibroblasts, and four viruses isolated in this way had all acquired point mutations in vhs which rescued viral mRNA export and late protein translation. However, unlike a virus deleted for vhs, these viruses still induced the degradation of cellular mRNA, suggesting that vhs mutation in the absence of VP22 is necessary to overcome a disturbance in mRNA export rather than mRNA degradation. The ultimate outcome of secondary mutations in vhs is therefore the rescue of virus-induced CPE caused by late protein synthesis, and while there is a clear selective pressure on HSV1 to mutate vhs for optimal production of late structural proteins, the purpose of this is over and above that of virus production. Author SummaryHSV is a human pathogen that lytically infects cells of the epidermis. Following viral genome replication, structural proteins are produced in abundance to enable the rapid assembly and release of large quantities of infectious progeny. Infected cells also exhibit cytopathic effect (CPE), morphological changes that are exemplified by cell rounding and the breakage of cell-to-cell contacts, facilitating virus dissemination. Here we show that HSV1 with a mutation that results in the nuclear retention of viral mRNA and concomitant shutdown of late protein synthesis, also fails to cause CPE. However, unexpectedly, we found that this virus is still able to release large numbers of infectious virus which can spread between cells without any evidence of cell damage. Nonetheless, despite efficient virus productivity, this virus spontaneously mutates to rescue late protein production and CPE, with mutations mapping to the process of mRNA export. There is therefore a clear selective pressure on HSV1 to optimize the synthesis of late structural proteins, but the purpose of this is over and above that of virus production, a result that has implications for why viruses in general express such large amounts of structural proteins.

microbiology↗

bioRxiv2022

Broadly neutralizing antibodies target the coronavirus fusion peptide

The potential for future coronavirus outbreaks highlights the need to develop strategies and tools to broadly target this group of pathogens. Here, using an epitope-agnostic approach, we identified six monoclonal antibodies that bound to spike proteins from all seven human-infecting coronaviruses. Epitope mapping revealed that all six antibodies target the conserved fusion peptide region adjacent to the S2 cleavage site. Two antibodies, COV44-62 and COV44-79, broadly neutralize a range of alpha and beta coronaviruses, including SARS-CoV-2 Omicron subvariants BA.1 and BA.2, albeit with lower potency than RBD-specific antibodies. In crystal structures of Fabs COV44-62 and COV44-79 with the SARS-CoV-2 fusion peptide, the fusion peptide epitope adopts a helical structure and includes the arginine at the S2 cleavage site. Importantly, COV44-79 limited disease caused by SARS-CoV-2 in a Syrian hamster model. These findings identify the fusion peptide as the target of the broadest neutralizing antibodies in an epitope-agnostic screen, highlighting this site as a candidate for next-generation coronavirus vaccine development. One-Sentence SummaryRare monoclonal antibodies from COVID-19 convalescent individuals broadly neutralize coronaviruses by targeting the fusion peptide.

immunology↗

bioRxiv2022

Fish microbiomes 101: disentangling the rules governing marine fish mucosal microbiomes across 101 species

Fish are the most diverse and widely distributed vertebrates, yet little is known about the microbial ecology of fishes nor the biological and environmental factors that influence the fish microbiome. The microbiota from 101 species of Southern California marine fishes, spanning 22 orders, 55 families, and 83 genera representing ~25% of local marine fish diversity, was analyzed to identify patterns that explain microbial diversity patterns in a geographical subset of marine fish biodiversity. We compared fish microbiomes (gill, skin, midgut, and hindgut) using alpha, beta, and gamma diversity along with establishing a novel method to estimate microbial biomass (Qiime2 plugin katharoseq). For oceanic fishes from the neritic zone, host size and distance from shore were negatively associated with microbial biomass densities and diversity in the gills. Body site was the strongest driver for beta diversity with strong evidence of phylosymbiosis observed across the gill, skin, and hindgut, but not midgut. The majority of microbes from all fish body sites were of unknown origin but overall sea water generally contributes more microbes to fish mucus compared to marine sediment. In a meta-analysis of vertebrate hindguts (569 species), mammals had the highest gamma diversity when controlling for host species number while fishes had the highest percent of unique microbial taxa (92%). In fishes, the midgut, gill, and skin contains the majority of microbial diversity which collectively can be 5.5 times higher than the hindgut. The composite dataset will be useful to vertebrate microbiome researchers and fish biologists interested in microbial ecology with applications in aquaculture and fisheries management.

ecology↗

bioRxiv2020

Contagious Antibiotic Resistance: Plasmid Transfer Among Bacterial Residents of the Zebrafish Gut

By characterizing the trajectories of antibiotic resistance gene transfer in bacterial communities such as the gut microbiome, we will better understand the factors that influence this spread of resistance. Our aim was to investigate the host network of a multi-drug resistance broad-host-range plasmid in the culturable gut microbiome of zebrafish. This was done through in vitro and in vivo conjugation experiments with Escherichia coli as donor of the plasmid pB10::gfp. When this donor was mixed with the extracted gut microbiome, only transconjugants of Aeromonas veronii were detected. In separate matings between the same donor and four prominent isolates from the gut microbiome, the plasmid transferred to two of these four isolates, A. veronii and Plesiomonas shigelloides, but not to Shewanella putrefaciens and Vibrio mimicus. When these A. veronii and P. shigelloides transconjugants were the donors in matings with the same four isolates, the plasmid now also transferred from A. veronii to S. putrefaciens. P. shigelloides was unable to donate the plasmid and V. mimicus was unable to acquire it. Finally, when the E. coli donor was added in vivo to zebrafish through their food, plasmid transfer was observed in the gut but only to Achromobacter sp., a rare member of the gut microbiome. This work shows that the success of plasmid-mediated antibiotic resistance spread in a gut microbiome depends on the donor-recipient species combinations and therefore their spatial arrangement. It also suggests that rare gut microbiome members should not be ignored as potential reservoirs of multi-drug resistance plasmids from food. ImportanceTo understand how antibiotic resistance plasmids end up in human pathogens it is crucial to learn how, where and when they are transferred and maintained in members of bacterial communities such as the gut microbiome. To gain insight into the network of plasmid-mediated antibiotic resistance sharing in the gut microbiome, we investigated the transferability and maintenance of a multi-drug resistance plasmid among the culturable bacteria of the zebrafish gut. We show that the success of plasmid-mediated antibiotic resistance spread in a gut microbiome can depend on which species are involved, as some are important nodes in the plasmid-host network and others dead-ends. Our findings also suggest that rare gut microbiome members should not be ignored as potential reservoirs of multi-drug resistance plasmids from food.

microbiology↗

bioRxiv2020

Scanning ion conductance microscopy reveals differences in the ionic environments of gram positive and negative bacteria

This paper reports on the use of scanning ion conductance microscopy (SICM) to locally map the ionic properties and charge environment of two live bacterial strains: the gramnegative Escherichia coli and the gram-positive Bacillus subtilis. SICM results find heterogeneities across the bacterial surface, and significant differences among the grampositive and -negative bacteria. The bioelectrical environment of the B. subtilis was found to be considerably more negatively charged compared to E. coli. SICM measurements, fitted to a simplified finite element method (FEM) model, revealed surface charge values of -80 to -140 mC m-2 for the gram-negative E. coli. The gram-positive B. subtilis show a much higher conductivity around the cell wall, and surface charge values between -350 and -450 mC m-2 were found using the same simplified model. SICM was also able to detect regions of high negative charge near B. subtilis, not detected in the topographical SICM response and attributed to extracellular polymeric substance. To further explore how the B. subtilis cell wall structure can influence the SICM current response, a more comprehensive FEM model, accounting for the physical properties of the gram-positive cell wall, was developed. The new model provides a more realistic description of the cell wall and allowed investigation of the relation between its key properties and SICM currents, building foundations to further investigate and improve understanding of the gram-positive cellular microenvironment. O_FIG_DISPLAY_L [Figure 1] M_FIG_DISPLAY C_FIG_DISPLAY

microbiology↗