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Doherty, E.

Publications and source records attributed to Doherty, E..

6 recordsLinked to original sources

Identification of Lupus Immune Complex-Driven Pathogenic Pro-inflammatory Monocytes and Macrophages in Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE or lupus) is an autoimmune disease characterized by anti-nuclear antibody (ANA) production and inflammation, though the mechanisms by which ANAs induce inflammation and tissue injury are incompletely understood. Here, we identified distinct subsets of mononuclear phagocytes (MPs), including monocytes (Mo) and macrophages (M{Phi}), driven by lupus immune complex (IC), comprised of ANAs and their target antigens. scRNA-seq of human Mo incubated with U1-snRNP (snRNP) lupus IC revealed expansion of distinct pro-inflammatory Mo subsets with upregulation of inflammatory genes including those encoding cytokines, NLRP3, and transcription factors. These transcriptomic changes strongly correlated with protein expression, as determined by proteomic analysis. Mo developed similar pro-inflammatory transcriptomic changes in response to other lupus ICs containing anti-dsDNA and Ro60 antibodies. Interrogation of scRNA-seq datasets from the skin, kidney, and peripheral blood of lupus patients revealed the presence and expansion of pro-inflammatory Mo and M{Phi} populations exhibiting transcriptomic signatures similar to those observed in lupus IC-stimulated Mo. Some of these cells expressing the snRNP IC gene signature exhibited low expression of the type I IFN signature, suggesting that lupus IC and type I IFN signaling may independently affect Mo subsets. In lupus nephritis, infiltration of CD68+ M{Phi} expressing NLRP3 was associated with treatment outcomes. Inhibiting activation of the transcription factor ETS2, a master regulator of Mo/M{Phi}-driven inflammation, attenuated lupus IC-induced activation of pro-inflammatory Mo. Collectively, these findings provide novel insights into the role of lupus IC-driven pro-inflammatory MPs in the pathogenesis of SLE and highlight their relevance as therapeutic targets. Significance StatementSystemic lupus erythematosus (SLE or lupus) is a multi-systemic autoimmune inflammatory disease characterized by anti-nuclear antibody (ANA) production. Lupus immune complex (IC), consisting of ANAs and their target antigens, likely play a critical role in the pathogenesis of lupus through activation of mononuclear phagocytes (MPs), including monocytes (Mo) and macrophages (M{Phi}), which can produce an array of inflammatory molecules. Using transcriptomic and proteomic analyses, our study identified distinct pro-inflammatory Mo populations driven by lupus IC, along with expansion of similar pro-inflammatory Mo and M{Phi} subsets in the skin, kidneys, and peripheral blood of lupus patients. These findings provide novel insights into the pathogenic role of lupus IC-driven pro-inflammatory MPs and support a scientific rationale for therapeutically targeting these cells. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=155 HEIGHT=200 SRC="FIGDIR/small/700902v2_ufig1.gif" ALT="Figure 1"> View larger version (43K): org.highwire.dtl.DTLVardef@1839430org.highwire.dtl.DTLVardef@175dd1dorg.highwire.dtl.DTLVardef@107b54forg.highwire.dtl.DTLVardef@11096b0_HPS_FORMAT_FIGEXP M_FIG C_FIG

immunology↗

Multimodal imaging reveals a lysosomal drug reservoir that drives heterogeneous distribution of PARP inhibitors

For all drugs, effective target engagement requires sufficient intracellular concentrations of drug to be reached, but whether tumour heterogeneity impacts drug distribution and efficacy is poorly studied. PARP inhibitors have transformed treatment of high-grade serous ovarian carcinoma (HGSOC), but resistance remains a clinical hurdle in this highly heterogeneous tumour type. We developed a patient-derived explant multi-modal imaging pipeline, which demonstrated that cell-intrinsic PARP inhibitor accumulation is highly variable, both between patients and within tumours. Spatial transcriptomics revealed enrichment of apoptotic and lysosomal signatures in high-drug regions. Rucaparib, an intrinsically fluorescent PARP inhibitor, accumulates heterogeneously at the single-cell level, with rucaparib-high cells demonstrating increased drug response relative to rucaparib low. Mechanistically, lysosomal sequestration creates a rucaparib reservoir that determines drug levels in the nucleus. Perturbation of lysosomal content altered intracellular levels of weak base PARP inhibitors rucaparib and niraparib, but not olaparib. Together these data suggest that lysosomes act as a reservoir for a subset of PARP inhibitor drugs to improve drug response.

cancer biology↗

Microphysiological uremia model reveals biophysical potentiators of vascular dysfunction

Cardiovascular disease is a leading cause of mortality in individuals with chronic kidney disease. Hypertension, common among patients with chronic kidney disease, is a major contributor to both kidney damage and the heightened cardiovascular risk in these patients. Advanced chronic kidney disease is associated with elevated levels of circulating uremic toxins, particularly indoxyl sulfate and p-cresyl sulfate, and are known to exacerbate cardiovascular risk by promoting inflammatory processes, including monocyte adhesion, rolling, and extravasation. However, despite the established link between chronic kidney disease and cardiovascular disease, the specific role of uremic toxins in monocyte-endothelial interactions in hypertensive settings remains largely underexplored. In this study, we developed a 3D microfluidic model to examine the effects of indoxyl sulfate on monocyte adhesion and extravasation across engineered microvessels embedded in collagen hydrogels with different densities under controlled luminal pressure. We found that elevated pressure alone significantly enhanced monocyte adhesion and extravasation, regardless of matrix density, and that the uremic environment further increased these effects. Additionally, denser hydrogels primed THP-1 monocyte cells toward a pro-inflammatory like phenotype with reduced phagocytic capacity, while softer hydrogels induced an anti-inflammatory like phenotype with enhanced phagocytosis. However, exposure to the uremic environment diminished phagocytosis and shifted cells toward a pro-inflammatory like state, irrespective of matrix density. The presented approach has the potential to experimentally dissect multiple factors that contribute to elevated cardiovascular risks in chronic kidney disease patients and improve the understanding of mechanisms involved in monocyte dynamics in chronic kidney disease- related cardiovascular disease.

bioengineering↗

Towards Ecological Measurement of Complex Cognitive Processes: Functional-Near Infrared Spectroscopy of Brain Activity During Reading

Functional magnetic resonance imaging (fMRI) has provided unparalleled insights into the fundamental neural mechanisms governing human cognition, including complex processes such as reading. Here, we leverage the wealth of prior fMRI work to capture reading outside the MRI scanner using functional near infra-red spectroscopy (fNIRS). In a large sample of participants (n = 82) we observe significant prefrontal and temporal fNIRS activations during reading, which are largely reliable across participants, therefore providing a robust validation of prior fMRI work on reading-related language processing. These results lay the groundwork towards developing adaptive systems capable of assisting these higher-level processes, for example to support readers and language learners. This work also contributes to bridging the gap between laboratory findings and real-world applications in the realm of cognitive neuroscience.

neuroscience↗

Mucus production, host-microbiome interactions, hormone sensitivity, and innate immune responses modeled in human endo- and ecto-cervix chips

Modulation of mucus production by the human endo- and ecto-cervical epithelium by steroid hormones and associated interactions with commensal microbiome play a central role in the physiology and pathophysiology of the female reproductive tract. However, most of our knowledge about these interactions is based on results from animal studies or in vitro models that fail to faithfully mimic the mucosal environment of the human cervix. Here we describe microfluidic organ-on-a-chip (Organ Chip) models of the human cervical mucosa that recreate the cervical epithelial-stromal interface with a functional epithelial barrier and produce abundant mucus that has compositional, biophysical, and hormone-responsive properties similar to the living cervix. Application of continuous fluid flow to chips lined with primary human cervical epithelial cells from a commercial source that contained a mixture of primary human ecto- and endo-cervical epithelial cells promoted preferential expression of the ecto-cervical phenotype, whereas use of periodic flow including periods of stasis induced endo-cervical specialization. When the periodic flow Cervix Chips were co-cultured with living Lactobacillus crispatus and Gardnerella vaginalis bacterial communities to respectively mimic the effects of human host interactions with optimal (healthy) or non-optimal (dysbiotic) microbiome associated with an ascending infection in the female reproductive tract, significant differences in tissue innate immune responses, barrier function, cell viability and protein profile, and mucus composition were detected reminiscent of those observed in vivo. Thus, these Organ Chip models of human cervix provide a physiologically relevant experimental in vitro model to study cervical mucus physiology and its role in human host-microbiome interactions as well as a potential preclinical testbed for development of therapeutic interventions to enhance womens health.

bioengineering↗

Vaginal microbiome-host interactions modeled in a human vagina-on-a-chip

BackgroundA dominance of non-iners Lactobacillus species in the vaginal microbiome is optimal and strongly associated with gynecological and obstetric health, while the presence of diverse obligate or facultative anaerobic bacteria and a paucity in Lactobacillus species, similar to communities found in bacterial vaginosis (BV), is considered non-optimal and associated with adverse health outcomes. Various therapeutic strategies are being explored to modulate the composition of the vaginal microbiome; however, there is no human model that faithfully reproduces the vaginal epithelial microenvironment for preclinical validation of potential therapeutics or testing hypotheses about vaginal epithelium-microbiome interactions. ResultsHere, we describe an organ-on-a-chip (Organ Chip) microfluidic culture model of the human vaginal mucosa (Vagina Chip) that is lined by hormone-sensitive, primary vaginal epithelium interfaced with underlying stromal fibroblasts, which sustains a low physiological oxygen concentration in the epithelial lumen. We show that the Vagina Chip can be used to assess colonization by optimal L. crispatus consortia as well as non-optimal Gardnerella vaginalis-containing consortia, and to measure associated host innate immune responses. Co-culture of the L. crispatus consortia was accompanied by maintenance of epithelial cell viability, accumulation of D- and L-lactic acid, maintenance of a physiologically relevant low pH, and down regulation of proinflammatory cytokines. In contrast, co-culture of G. vaginalis-containing consortia in the Vagina Chip resulted in epithelial cell injury, a rise in pH, and upregulation of proinflammatory cytokines. ConclusionThis study demonstrates the potential of applying human Organ Chip technology to create a preclinical model of the human vaginal mucosa that can be used to better understand interactions between the vaginal microbiome and host tissues, as well as to evaluate the safety and efficacy of live biotherapeutics products.

microbiology↗