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Taylor, R. M.

Publications and source records attributed to Taylor, R. M..

6 recordsLinked to original sources

Nano- and microplastics in pediatric tonsil tissue: bioaccumulation, distribution, and immunomodulatory effects in human lymphoid aggregate organoids

Nano- and microplastics (NMPs), by-products of the fragmentation and degradation of plastic products, are ubiquitous environmental contaminants, yet their burden in pediatric immune tissues and functional consequences for developing immunity remain unknown. Here we report the first comprehensive characterization of NMPs in surgically excised pediatric tonsils (n = 30) using pyrolysis gas chromatography- mass spectrometry (Py-GC/MS), Nile Red fluorescence microscopy, and optical photothermal infrared (O-PTIR) spectroscopy. NMPs were detected in all specimens, with polystyrene, polyethylene, polyethylene terephthalate, and acrylonitrile butadiene styrene present in >90% of samples. To bridge clinical exposure data with mechanistic insight, we formulated a cryo-milled multi-polymer mixture reflecting the patient-derived polymer profile and challenged human lymphoid aggregate culture (HLAC) tonsil organoids at environmentally relevant concentrations. Multiplexed cytokine profiling of culture supernatants revealed a robust early inflammatory response at day 3, with significant upregulation of IL-6 (p = 0.011) and MIP-1{beta}/CCL4 (p = 0.011), followed by convergence toward control levels by day 14. Functional cytokine modules spanning immune, metabolic, structural, and growth factor pathways showed coordinated deviation from controls at day 3 post-exposure with subsequent normalization. Fluorescence-guided depth profiling demonstrated time-dependent penetration of 100 nm particles into organoid aggregates (70% tissue depth at day 3 versus 95% at day 14), and transmission electron microscopy revealed intracellular polyethylene within lymphocyte lysosomes. These findings establish pediatric tonsils as a sentinel tissue for NMP bioaccumulation and demonstrate that environmentally relevant polymer mixtures elicit transient but significant immunomodulatory responses in human lymphoid tissue, with implications for mucosal and systemic immune health in children. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=83 SRC="FIGDIR/small/728317v1_ufig1.gif" ALT="Figure 1"> View larger version (19K): org.highwire.dtl.DTLVardef@19395f4org.highwire.dtl.DTLVardef@5a0380org.highwire.dtl.DTLVardef@19c0741org.highwire.dtl.DTLVardef@a052c5_HPS_FORMAT_FIGEXP M_FIG Structure: Translational pipeline from clinical tissue characterization to patient-informed preclinical modeling of nano-microplastic (NMP) exposure in pediatric lymphoid tissue. Pediatric tonsil tissue collected from clinically indicated tonsillectomies underwent tissue digestion for NMP characterization to identify NMP type and size distributions. In parallel, tonsil tissue was used to generate human lymphoid aggregate culture (HLAC) organoids that recapitulate the cellular complexity of the native tissue. These patient-derived organoids were then exposed to environmentally relevant compositions and concentrations of NMPs over time-course experiments, with longitudinal assessment of immunomodulatory responses including cytokine profiling and functional readouts. This bedside-to-bench approach establishes a physiologically relevant human system for investigating NMP-immune interactions, bridging clinical tissue analysis with mechanistic preclinical modeling to inform understanding of pediatric environmental exposures and their potential health impacts. C_FIG

immunology↗

Immunization with VLP-based vaccines induces high IgG antibody titers in dermal interstitial fluid

Although antibodies often exert their effects within the interstitium, the distribution of antibodies within extravascular tissue compartments is not typically measured. Here, IgG titers in peripheral blood and dermal interstitial fluid (ISF) were compared after intramuscular and intradermal immunization with virus-like particle (VLP)-based vaccines. Antibody titers and durability in serum and ISF were similar, indicating that VLP-based vaccines can efficiently elicit strong antibody responses in the skin.

immunology↗

Large-Scale Comparative Transcriptomic Analysis of CHO Cell Functional Adaptation to Recombinant Monoclonal Antibody Production

To comparatively evaluate cellular constraints on recombinant monoclonal antibody (mAb) production by Chinese Hamster Ovary (CHO) cells, we analysed the transcriptomes of 24 clonally derived CHO cell lines engineered with PiggyBac transposon technology to stably produce four recombinant monoclonal antibodies (mAbs) at varying specific production rates. Fed-batch cultures were sampled at exponential (day 5) and stationary (day 10) phases of culture for analysis by RNA-Seq. Recombinant mRNAs accounted for a large proportion of total mRNA across all clones, and efficient use of heavy chain (HC) mRNA to synthesise recombinant mAb (qP per HC mRNA) varied significantly with respect to both mAb product and cell line. Comparative bioinformatic analyses of CHO transcriptomes focussed on mAb specific production rate and utilised both data-driven and hypothesis-led approaches, specifically (i) production or non-production of recombinant mAb, (ii) changes in the abundance of functional groups of mRNAs abundance with mAb specific production rate and (iii) comparative analysis of informatically-mined gene subsets associated with cellular functions hypothesised to impact recombinant mAb synthesis and secretion. These analyses revealed widespread constitutive and adaptive changes in mRNA abundance associated with mAb production across a variety of cellular functions. Typically, most mechanistically consistent changes in mRNA abundance co-varying with mAb production were evident at the stationary phase sample point. These data revealed both recombinant mAb-specific limitations on cellular synthetic capacity and a generic adaptive strategy used by CHO cells to support high-level mAb production. The latter was achieved by directed and permissive regulation of endoplasmic reticulum and other processes to accommodate increased synthetic flux.

bioengineering↗

Stem cell-derived macrophages as a new platform for studying host-pathogen interactions in livestock

Infectious diseases of farmed and wild animals pose a recurrent threat to food security and human health. The macrophage, a key component of the innate immune system, is the first line of defence against many infectious agents and plays a major role in shaping the adaptive immune response. However, this phagocyte is a target and host for many pathogens. Understanding the molecular basis of interactions between macrophages and pathogens is therefore crucial for the development of effective strategies to combat important infectious diseases. We explored how pluripotent stem cells (PSCs) can provide a limitless in vitro supply of genetically and experimentally tractable macrophages from livestock. Porcine and bovine PSC-derived macrophages (PSCdMs) exhibited molecular and functional characteristics of ex vivo primary macrophages. Pig PSCdMs were productively infected by Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) and African Swine Fever Virus (ASFV), two of the most economically important and devastating viruses in pig farming. Moreover, Pig PSCdMs were readily amenable to genetic modification by CRISPR/Cas9 gene editing applied in parental stem cells, or directly by lentiviral vector transduction. PSCs and differentiated derivatives therefore provide a useful and ethical experimental platform to investigate the genetic and molecular basis of host-pathogen interactions in livestock.

immunology↗

Do pneumococcal conjugate vaccines (PCVs) reduce childhood pneumonia mortality? An assessment across socioeconomic groups in Brazil

BackgroundUnderstanding the real-world impact of pneumococcal conjugate vaccines (PCVs) on pneumonia mortality is critical, given the expectation that PCVs can substantially reduce the burden of pneumonia deaths in children under five years. However, surprisingly few post-vaccine introduction studies have estimated the benefit of PCVs for childhood mortality, and results have been inconsistent.\n\nMethodsWe investigated the long-term trends in child pneumonia mortality in Brazil (1980-present) and assessed the impact of PCV10 on childhood pneumonia mortality, both nationally and in municipalities stratified by socioeconomic status (SES), after the vaccine was introduced in Brazil in 2010.\n\nFindingsBetween 1980 and 2010, a period when Brazils Human Development Index (HDI) rose from 0.55 to 0.71, national pneumonia mortality in children under five decreased 10-fold. Despite rapid uptake of PCV10 following its introduction in 2010, our primary analytical method found no significant decline in national childhood pneumonia mortality, although a secondary analysis found a 10 percent decline in some but not all strata. However, at the municipal level we found significant reductions in childhood pneumonia mortality of up to 24% in low SES strata.\n\nInterpretationContrary to expectations, we found that PCV use led to at best modest savings in childhood pneumonia mortality at the national level in a middle-income country. In contrast, we found evidence that PCV led to larger reductions in low-income settings; a similar benefit might occur when PCVs are introduced in other low-SES settings. The long-term findings underscore that improvements in nutrition, hygiene, education, and healthcare play a major role in reducing pneumonia mortality.\n\nFundingThis work was funded by a grant from the Bill & Melinda Gates Foundation (OPP1114733). DMW also acknowledges support from the Bill and Melinda Gates Foundation (OPP1176267) and the National Institute of Allergy and Infectious Diseases (R01AI123208)

epidemiology↗

Natively Oxidized Amino Acid Residues in the Spinach Cytochrome b6f Complex

The cytochrome b6f complex of oxygenic photosynthesis produces substantial levels of reactive oxygen species (ROS). It has been observed that the ROS production rate by b6f is 10-20 fold higher than that observed for the analogous respiratory cytochrome bc1 complex. The types of ROS produced (O2*-,1O2, and, possibly, H2O2) and the site(s) of ROS production within the b6f complex has been the subject of some debate. Proposed sources of ROS have include the heme bp, PQp*- (possible sources for O2*-), the Rieske iron-sulfur cluster (possible source of O2*- and/or H2O2), Chl a (possible source of 1O2) and heme Cn (possible source of O2*- and/or H2O2). Our working hypothesis is that amino acid residues proximal to the ROS production sites will be more susceptible to oxidative modification than distant residues. In the current study, we have identified natively oxidized amino acid residues in the subunits of the spinach cytochrome b6f complex. The oxidized residues were identified by tandem mass spectrometry using the MassMatrix Program. Our results indicate that numerous residues, principally localized near p-side cofactors and Chl a, were oxidatively modified. We hypothesize that these sites are sources for ROS generation in the spinach cytochrome b6f complex.

biochemistry↗