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Biology subjects

Jones, H. E.

Publications and source records attributed to Jones, H. E..

9 recordsLinked to original sources

Individual Host Variation in Single-cell Responses to Enteroaggregative Escherichia coli Infection Modeled with Human Colon Organoids

Enteroaggregative Escherichia coli (EAEC) is a leading cause of diarrhea disease worldwide. Interestingly, EAEC disease outcomes vary dramatically among infected individuals, ranging from asymptomatic colonization to acute and chronic diarrhea. While previous research has focused on EAEC virulence factors, emerging evidence suggests that host genetic and cellular background may be equally important in determining disease susceptibility. To understand host-driven disease heterogeneity, we performed single-cell RNA sequencing on human colon organoids (HCOs) derived from three healthy adult donors following EAEC 042 infection. Surprisingly, despite comparable EAEC adherence across donors, we observed striking donor-specific responses to infection at multiple levels. A total of seven distinct colonic epithelial cell clusters were identified, with striking donor-specific baseline compositions. Following infection, the HCO donors exhibited three distinct response phenotypes evident in both cell type remodeling and gene regulation: hyperresponsive, intermediate, and non-responsive. We further observed extensive donor-specific cell-cell communication networks at baseline and after EAEC infection. This study suggests that the heterogeneity in host epithelial response to EAEC infection extends to the single-cell level. These findings establish a paradigm for understanding infectious disease susceptibility through the human organoid model system. IMPORTANCEUnderstanding why similar pathogen exposures produce vastly different clinical outcomes is critical for combating infectious diseases. By conducting single-cell RNA sequencing on human colon organoids derived from three different donors, we show that each donor possesses unique intrinsic cellular compositions and distinct transcriptomic responses to EAEC infection. These findings challenge the traditional pathogen-focused paradigm and highlight the critical role of host factors in infectious disease outcomes. This study also validates human organoids as a powerful platform for studying host heterogeneity, which may help predict disease susceptibility and optimize treatment for diverse patient populations in the future.

microbiology↗

PDGFRα is required for postnatal cerebral perivascular fibroblast development

Perivascular fibroblasts (PVFs) are a cell type associated with large diameter blood vessels in the brain and spinal cord parenchyma and leptomeninges. PVFs have previously defined roles in injury and neuroinflammatory diseases and predicted roles in supporting neurovascular function. The temporal dynamics of PVF development in the pre- and postnatal cerebral cortex have recently been described, however the molecular mechanisms that underly PVF development have not been identified. PVFs express both platelet derived growth factor receptors (PDGFRs), PDGFR and PDGFR{beta}. Here we investigate the role of PDGF signaling in PVF development. We use immunohistochemistry and RNA transcript detection methods to show developmental expression of PDGFRs by PVFs and examine distribution of PDGF ligand expression in the brain. We show that postnatal deletion of PDGFR in fibroblasts using the Col1a2-CreERT mouse line significantly impairs PVF coverage of cerebral vessels at postnatal day 10. Perivascular macrophages, a cell type previously shown to co-develop with PVFs, have impaired cerebral vessel coverage in conditional mutants that is similar to PVF coverage defects. This work establishes a requirement for PDGFR signaling in PVF development and may shed light upon the potential pathways that are over-activated in PVFs in injury and disease contexts.

developmental biology↗

Leptomeningeal Neural Organoid (LMNO) Fusions as Models to Study Meninges-Brain Signaling

Neural organoids derived from human induced pluripotent stem cells (iPSCs) provide a model to study the earliest stages of human brain development, including neurogenesis, neural differentiation, and synaptogenesis. However, neural organoids lack supportive tissues and some non-neural cell types that are key regulators of brain development. Neural organoids have instead been co-cultured with non-neural structures and cell types to promote their maturation and model interactions with neuronal cells. One structure that does not form de novo with neural organoids is the meninges, a tri-layered structure that surrounds the CNS and secretes key signaling molecules required for mammalian brain development. Most studies of meninges-brain signaling have been performed in mice or using two-dimensional (2D) cultures of human cells, the latter not recapitulating the architecture and cellular diversity of the tissue. To overcome this, we developed a co-culture system of neural organoids generated from human iPSCs fused with fetal leptomeninges from mice with fluorescently labeled meninges (Col1a1-GFP). These proof-of-concept studies test the stability of the different cell types in the leptomeninges (fibroblast and macrophage) and the fused brain organoid (progenitor and neuron), as well as the interface between the organoid and meningeal tissue. We test the longevity of the fusion pieces after 30 days and 60 days in culture, describe best practices for preparing the meninges sample prior to fusion, and examine the feasibility of single or multiple meninges pieces fused to a single organoid. We discuss potential uses of the current version of the LMNO fusion model and opportunities to improve the system.

cell biology↗

Meningeal origins and dynamics of perivascular fibroblast development on the mouse cerebral vasculature

Perivascular fibroblasts (PVFs) are a fibroblast-like cell type that reside on large-diameter blood vessels in the adult meninges and central nervous system (CNS). PVFs drive fibrosis following injury but their homeostatic functions are not well detailed. In mice, PVFs were previously shown to be absent from most brain regions at birth and are only detected postnatally within the cerebral cortex. However, the origin, timing, and cellular mechanisms of PVF development are not known. We used Col1a1-GFP and Col1a2-CreERT transgenic mice to track PVF developmental timing and progression in postnatal mice. Using a combination of lineage tracing and in vivo imaging we show that brain PVFs originate from the meninges and are first seen on parenchymal cerebrovasculature at postnatal day (P)5. After P5, PVF coverage of the cerebrovasculature rapidly expands via mechanisms of local cell proliferation and migration from the meninges, reaching adult levels at P14. Finally, we show that PVFs and perivascular macrophages (PVMs) develop concurrently along postnatal cerebral blood vessels, where the location and depth of PVMs and PVFs highly correlate. These findings provide the first complete timeline for PVF development in the brain, enabling future work into how PVF development is coordinated with cell types and structures in and around the perivascular spaces to support normal CNS vascular function. SummaryBrain perivascular fibroblasts migrate from their origin in the meninges and proliferate locally to fully cover penetrating vessels during postnatal mouse development.

developmental biology↗

Formation and function of the meninges arachnoid barrier around the developing brain

Barriers at the level of the brain endothelium, choroid plexus, and meninges strictly regulate movement of molecules and cells into and out of the central nervous system (CNS). In contrast to the blood-brain barrier and choroid plexus epithelial barrier, developmental timing and function of the meningeal arachnoid barrier, a layer of epithelial-like cells connected by tight and adherens junctions, is largely unknown. To begin to address this, we mined our E14.5 mouse single cell transcriptomic (scRNA-seq) meningeal fibroblast data set and identified the repression of Wnt-{beta}-catenin signaling as a key mechanism underlying the specification of epithelial-like arachnoid barrier cells from Collagen 1+ and Crabp2+ mesenchymal meningeal precursors. We show that elevating Wnt-{beta}-catenin signaling in prenatal meningeal mesenchymal cells prevented the development of arachnoid barrier cells. In the absence of dorsal arachnoid barrier cells, the prenatal meninges and brain are penetrable to biocytin-TMR and Streptococcus agalactiae (Group B Streptococcus, GBS), the leading pathogen known to drive life-threatening neonatal meningitis. We show that a layer of Claudin 11 (tight junction) and E-cadherin (adherens junction) expressing arachnoid barrier cells appear around the mouse brain from E13-E15 and the emergence of a functional barrier by E17 coincides with junctional localization of Claudin 11. Postnatal growth of the arachnoid barrier is marked initially by proliferation and later re-organization of junctional domains. This work provides fundamental knowledge on development and prenatal function of a meningeal arachnoid barrier, and novel tools for future studies on regional functions of this CNS barrier in the meninges.

developmental biology↗

Techniques for visualizing fibroblast-vessel interactions in the developing and adult CNS

Fibroblasts are found associated with blood vessels in various locations across the CNS: in the meninges, the choroid plexus, and in the parenchyma within perivascular spaces. CNS fibroblasts have been characterized using transcriptional profiling and a Col1a1-GFP mouse line used to identify CNS fibroblasts in vivo. However, current methods for visualizing CNS fibroblasts are lacking and, in particular, prevent adequate assessment of fibroblast-vessel interactions. Here, we describe methods for whole mount visualization of meningeal and choroid plexus fibroblasts, and optical tissue clearing methods for visualization of parenchymal vessel-associated fibroblasts. Importantly, these techniques can be combined with immunohistochemistry methods for labeling different cell types in the meninges and blood vasculature as well as EdU-based cell proliferation assays. These methods are ideal for visualization of vessel-fibroblast interactions in these CNS structures and provide significant improvement over traditional sectioning and staining methods. We expect these methods will advance studies of CNS fibroblast development and functions in homeostasis, injury, and disease.

neuroscience↗

A cellular atlas of the developing meninges reveals meningeal fibroblast diversity and function

The meninges, a multilayered structure that encases the CNS, is composed mostly of fibroblasts, along with vascular and immune cells. Meningeal fibroblasts are a vital source of signals that control neuronal migration and neurogenesis yet strikingly little is known about their development. We used single cell RNA sequencing to generate a cellular atlas of embryonic meningeal fibroblasts in control and Foxc1-KO mice in which severe CNS defects arise from failed meningeal fibroblast development. We report unique transcriptional signatures for dura, arachnoid and pial fibroblasts and identify S100a6 as the first unique marker of the pial layer. We describe a new meningeal fibroblast subtype marked by {micro}-Crystallin expression and show these cell types and markers are conserved in human fetal meninges. Our analysis demonstrates layer specific production of extracellular matrix components, transporter expression, and synthesis of secreted factors. Lastly, the cellular atlas of Foxc1-KO meninges provides insight into their severe phenotype, confirming a massive loss in arachnoid and dura fibroblasts and Foxc1-KO pial fibroblasts are so altered that they cluster as a different cell type based on gene expression. These studies provide an unprecedented view of meningeal fibroblast development, highlighting unexpected fibroblast diversity and function, while providing mechanistic insights into the meninges role in CNS development.

neuroscience↗

Tobacco exposure associated with oral microbiota oxygen utilization in the New York City Health and Nutrition Examination Study

PurposeThe effect of tobacco exposure on the oral microbiome has not been established. MethodsWe performed amplicon sequencing of the 16S ribosomal RNA gene V4 variable region to estimate bacterial community characteristics in 259 oral rinse samples, selected based on self-reported smoking and serum cotinine levels, from the 2013-14 New York City Health and Nutrition Examination Study. We identified differentially abundant operational taxonomic units (OTUs) by primary and secondhand tobacco exposure, and employed "microbe set enrichment analysis" to assess shifts in microbial oxygen utilization. ResultsCigarette smoking was associated with depletion of aerobic OTUs (Enrichment Score test statistic ES = -0.75, p = 0.002) with a minority (29%) of aerobic OTUs enriched in current smokers compared to never smokers. Consistent shifts in the microbiota were observed for current cigarette smokers as for non-smokers with secondhand exposure as measured by serum cotinine levels. Differential abundance findings were similar in crude and adjusted analyses. ConclusionResults support a plausible link between tobacco exposure and shifts in the oral microbiome at the population level through three lines of evidence: 1) a shift in microbiota oxygen utilization associated with primary tobacco smoke exposure, 2) consistency of abundance fold-changes associated with current smoking and shifts along the gradient of secondhand smoke exposure among non-smokers, and 3) consistency after adjusting for a priori hypothesized confounders. HighlightsO_LICigarette smoke was associated with microbial anaerobiosis in oral rinse specimens C_LIO_LIThe microbiome shifts associated with smoking and secondhand exposure were correlated C_LIO_LIShifts in oral bacterial oxygen utilization may mediate smoking and health outcomes C_LIO_LIWe propose "microbe set enrichment analysis" for interpreting shifts in the microbiome C_LI

epidemiology↗

Sociodemographic patterning in the oral microbiome of a diverse sample of New Yorkers

11.1 PurposeVariations in the oral microbiome are potentially implicated in social inequalities in oral disease, cancers, and metabolic disease. We describe sociodemographic variation of oral microbiomes in a diverse sample.\n\n1.2 MethodsWe performed 16S rRNA sequencing on mouthwash specimens in a subsample (n=282) of the 2013-14 population-based New York City Health and Nutrition Examination Study (NYC-HANES). We examined differential abundance of 216 operational taxonomic units (OTUs), and alpha and beta diversity by age, sex, income, education, nativity, and race/ethnicity. For comparison, we also examined differential abundance by diet, smoking status, and oral health behaviors.\n\n1.3 Results69 OTUs were differentially abundant by any sociodemographic variable (false discovery rate < 0.01), including 27 by race/ethnicity, 21 by family income, 19 by education, three by sex. We also found 49 differentially abundant by smoking status, 23 by diet, 12 by oral health behaviors. Genera differing for multiple sociodemographic characteristics included Lactobacillus, Prevotella, Porphyromonas, Fusobacterium.\n\n1.4 ConclusionsWe identified oral microbiome variation consistent with health inequalities, with more taxa differing by race/ethnicity than diet, and more by SES variables than oral health behaviors. Investigation is warranted into possible mediating effects of the oral microbiome in social disparities in oral, metabolic and cancers.\n\nHighlightsO_LIMost microbiome studies to date have had minimal sociodemographic variability, limiting what is known about associations of social factors and the microbiome.\nC_LIO_LIWe examined the oral microbiome in a population-based sample of New Yorkers with wide sociodemographic variation.\nC_LIO_LINumerous taxa were differentially abundant by race/ethnicity, income, education, marital status, and nativity.\nC_LIO_LIFrequently differentially abundant taxa include Porphyromonas, Fusobacterium, Streptococcus, and Prevotella, which are associated with oral and systemic disease.\nC_LIO_LIMediation of health disparities by microbial factors may represent an important intervention site to reduce health disparities, and should be explored in prospective studies.\nC_LI

epidemiology↗