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Turner, J. D.

Publications and source records attributed to Turner, J. D..

9 recordsLinked to original sources

The CCR2 inflammatory pathway is a target for improving severe disease and pulmonary inflammation in experimental COVID-19

SARS-CoV2 can induce an acute respiratory distress syndrome (ARDS), provoked by a dysregulated hyper-inflammatory pulmonary immune response. Here we used the keratinocyte-18 humanized angiotensin converting enzyme-2 (K18-hACE2) mouse model of SARS-CoV2, where expression of the CoV2 spike protein receptor, hACE-2, is restricted to epithelia, to characterize inflammatory pulmonary immune responses post-intranasal infections with the delta isolate SARS-CoV2({Delta} B.1.617.2). Immune-profiling by focused transcript analysis, inflammatory protein array, and multi-color flow cytometry, confirmed that clinically relevant markers of COVID-19 (IL-6, GM-CSF, neutrophils, inflammatory monocytes) were significantly elevated in lungs of mice at day 5 post-infection and that remdesivir anti-viral active metabolite (GS441524) treatment significantly modified SARS-CoV2{Delta} viral loads and pulmonary-specific inflammation. Chemokine ligands of CCR2 (CCL2/7/8) were amongst the top 5% upregulated pulmonary transcripts in a focused human infection response array to SARS-CoV2{Delta}. CCL2 was confirmed as elevated in protein assays in SARS-CoV2{Delta} infected lungs. To address functional relevance of the CCR2 pathway of inflammatory cell recruitment to the lungs mediating disease, mice were administered with anti-CCR2 antibody daily at point of infection for up to six days. Anti-CCR2 treated mice showed significant improved welfare scores, were protected from weight loss, modified myeloid pneumonitis, and displayed significantly blunted cytokine and chemokine response in the lungs, despite not affecting pulmonary viral loads. Our data supports therapeutic benefit of modifying CCR2-dependent cell recruitment in the treatment of viral-induced ARDS.

immunology↗

CD4+ tissue resident memory Th17 cells drive IL-17A-mediated joint pathology in Spondyloarthritis

ObjectivesInterleukin (IL)-17A is a key driver of Spondyloarthritis (SpA) joint pathology. We aimed to identify its cellular source in synovial tissue from patients with two forms of SpA namely Axial SpA (AxSpA) and Psoriatic arthritis (PsA). MethodsSynovial tissue from patients with SpA was profiled using single-cell RNA sequencing (scRNA-seq: AxSpA, n=5 and PsA, n=6) or spatial RNA profiling (PsA, n=4). CellPhoneDB was used to infer cell-cell communication. Tissue resident memory Th17 (TRM17)-like cells were generated in vitro using blood memory CD4+ T cells from SpA patients. An epigenetic inhibitor library, siRNA and clustered regularly interspaced short palindromic repeats (CRISPR) were used to identify epigenetic regulator(s) for TRM17. ResultsscRNA-seq showed that CD4+CXCR6+ TRM17 cells are the predominant spontaneous IL17A producers in SpA synovium. Cell-cell communication and single-cell spatial analysis support the interaction between TRM17 and CLEC10A+ dendritic cells, which were activated in SpA. Both sublining and lining fibroblasts in SpA synovium showed evidence of IL-17A activation. In vitro-generated CD4+ TRM17-like cells phenocopied joint tissue TRM17, producing IL-17A/F upon T cell receptor (TCR) stimulation, which was further enhanced by cytokines. Perturbation of BRD1 inhibited the generation of TRM17-like cells. ConclusionsCD4+ TRM17 cells are the predominant source of IL-17A in SpA synovial tissue. TCR stimulation is essential for the secretion of IL-17A by CD4+TRM17-like cells. The epigenetic regulator BRD1 contributes to the generation of CD4+TRM17. Depleting CD4+TRM17 cells in SpA is thus a therapeutic strategy with potential to induce long-term remission. Key messagesO_ST_ABSWhat is already known on this topicC_ST_ABSInterleukin (IL)-17A plays a key role in the immunopathogenesis of Spondyloarthritis (SpA), but its cellular source in joint tissue has not been determined previously. The induction and accumulation of CD4+ tissue resident memory Th17 (TRM17) cells following the clearance of pathogens has been described in skin, lung and kidney. Whether CD4+ TRM17 cells also accumulate in the joint and contribute to the pathology of SpA is not clear. What this study addsO_LICD4+ TRM17 cells are present in SpA synovial tissue and are the predominant source of IL17A C_LIO_LICD4+ TRM17 cells in SpA joints express IL17A without any in vitro exogenous stimulation C_LIO_LIT cell receptor (TCR) rather than cytokine stimulation is essential for IL-17A production by CD4+ TRM17-like cells C_LIO_LIThe epigenetic regulator BRD1 contributes to the generation of CD4+ TRM17-like cells. C_LI How this study might affect research, practice or policyOur findings identify CD4+ TRM17 cells as the primary source of IL-17A in SpA synovium, a previously unrecognized role for these cells. Key questions remain: How do CD4+ TRM17 cells relate to IL-17A producers in synovial fluid? What mechanisms induce and maintain them in the joint? How do they interact with other cells to promote arthritis? These questions warrant further investigation. In addition, our data suggest that targeting CD4+ TRM17 cells, the "factory" of IL-17A in SpA synovial tissue, has the potential to induce long-term remission, encouraging future efforts to develop new therapies to deplete CD4+ TRM17 cells in SpA.

immunology↗

Spatial programming of fibroblasts promotes resolution of tissue inflammation through immune cell exclusion

The role of fibroblasts in determining tissue topography and immune cell organisation within chronically inflamed tissues is poorly understood. Herein, we use multi-omic spatial analysis to define the cellular zonation pattern of the synovium in patients with inflammatory arthritis, identifying discrete tissue niches underpinned by spatially programmed subsets of synovial fibroblasts. We observe that perivascular fibroblasts switch on distinct matrix programs in response to cytokine signalling from neighbouring cells, forming adapted tissue niches that either permit or restrict immune cell trafficking. Specifically, IFN-{gamma}-responsive fibroblasts form a pathogenic lymphocyte-permissive niche that supports the persistence of leukocytes in the tissue, whilst TGF-{beta}-responsive, matrix-synthesising fibroblasts comprise a reparative niche, composed of a collagen-rich barrier around blood vessels that restricts leukocyte migration and promotes resolution of tissue inflammation. Augmentation of such endogenous pathways to promote resolution of inflammation may offer therapeutically tractable approaches for restoration of tissue homeostasis. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=99 SRC="FIGDIR/small/614064v1_ufig1.gif" ALT="Figure 1"> View larger version (45K): org.highwire.dtl.DTLVardef@1e6e4dborg.highwire.dtl.DTLVardef@1baee04org.highwire.dtl.DTLVardef@1608a1forg.highwire.dtl.DTLVardef@10c1edb_HPS_FORMAT_FIGEXP M_FIG O_FLOATNOGRAPHICAL ABSTRACTC_FLOATNO C_FIG

immunology↗

A dirofilariasis mouse model for heartworm preclinical research

Use of experimental cats and dogs in veterinary heartworm preclinical drug research is increasing. As a potential alternative primary in vivo heartworm preventative drug screen, we assessed lymphopenic mice with ablation of the interleukin-2/7 common gamma chain ({gamma}c) as susceptible to the larval development phase of D. immitis. Non-obese diabetic (NOD) Severe Combined ImmunoDeficient (SCID){gamma}c-/-(NSG / NXG) mice consistently yielded viable D. immitis larvae at 2-4 weeks post-infection across multiple experiments, different batches of infectious larvae inoculates, different isolates of D. immitis and at independent laboratories. Mice did not display any overt clinical signs associated with infection up to 4 weeks. Developing larvae were found in subcutaneous and muscle fascia tissues, the natural site of this stage of heartworm in dogs. Larvae retrieved from NSG / NXG mice were mid-L4 stage of development. Compared with 14-day in vitro propagated larvae, in vivo derived L4 were significantly larger and contained expanded Wolbachia endobacteria titres, determined by QPCR and Fluorescent in situ Hybridisation (FISH). We established an ex vivo 6-day L4 paralytic screening system against nematodicidal agents (moxidectin, levamisole) which highlighted discrepancies in relative drug sensitivities in comparison with in vitro reared L4 D. immitis. We demonstrated effective depletion of Wolbachia by 70-90% in D. immitis L4 following 2-7 day oral in vivo exposures of NSG / NXG infected mice with doxycycline or the rapid-acting investigational anti-Wolbachia drug, AWZ1066S. We validated the NSG / NXG mouse model as a filaricide drug screen by in vivo treatments with single injections of moxidectin, which mediated 60-88% reduction in L4 larvae at 14-28 days. Future adoption of the mouse model as a first-line efficacy screen will benefit end-user laboratories conducting research and development of novel heartworm preventatives via increased access, rapid turnaround and reduced costs whilst simultaneously decreasing need for experimental cat or dog use.

microbiology↗

A cellular and spatial map of salivary glands at single cell resolution reveals the functional basis of tertiary lymphoid structure formation in Sjogren's syndrome

The key role of tertiary lymphoid structures in autoimmune and non-autoimmune conditions has been recently appreciated. While many of the molecular mechanisms involved in tertiary lymphoid structure (TLS) formation have been identified, their cellular sources and their temporal and spatial relationship to each other during the development of TLS remain unknown. Here we have constructed a cellular and functional map of key components involved in the formation of TLS in the minor salivary glands (SG) in humans. We have confirmed the presence of an immunofibroblast cell state and identified an undescribed immunopericyte cell state with potential immunological functions within TLS. The identification of TLS cellular and functional properties and their relevant modulators provided by this analysis provides key therapeutic cues for TLS associated conditions in autoimmunity and cancer.

immunology↗

Structural requirements for dihydrobenzoxazepinone anthelmintics: actions against medically important and model parasites - Trichuris muris, Brugia malayi and Heligmosomoides polygyrus

Nine hundred million people are infected with the soil-transmitted helminths Ascaris lumbricoides (roundworm), hookworm, and Trichuris trichiura (whipworm). However, low single-dose cure rates of the benzimidazole drugs, the mainstay of preventative chemotherapy for whipworm, together with parasite drug resistance, mean that current approaches may not be able to eliminate morbidity from Trichuriasis. We are seeking to develop new anthelmintic drugs specifically with activity against whipworm as a priority, and previously identified a hit series of dihydrobenzoxazepinone (DHB) compounds that block motility of ex vivo Trichuris muris. Here we report a systematic investigation of the structure-activity relationship of the anthelmintic activity of DHB compounds. We synthesised 47 analogues, which allowed us to define features of the molecules essential for anthelmintic action, as well as broadening the chemotype by identification of dihydrobenzoquinolinones (DBQ) with anthelmintic activity. We investigated the activity of these compounds against other parasitic nematodes, identifying DHB compounds with activity against Brugia malayi and Heligmosomoides polygyrus. We also demonstrated activity of DHB compounds against the trematode Schistosoma mansoni, a parasite that causes schistosomiasis. These results demonstrate the potential of DHB and DBQ compounds for further development as broad-spectrum anthelmintics. Author summaryAround a billion people are infected by the soil transmitted helminths Ascaris, hookworm and whipworm. In the case of whipworm, the benzimidazole drugs, which are distributed to school children in affected areas, have low cure rates. This means that finding an improved treatment for whipworm is a priority. We previously identified five DHB compounds in a screen for new compounds active against whipworm. Here we systematically dissect these molecules, making 47 modified versions of the compounds. This allowed us to define the features of these compounds that are important for activity against whipworm. We also demonstrate activity of DHB compounds against other parasitic nematodes, and against Schistosoma mansoni, a trematode parasite. These results show the potential for further development of DHB compounds as broad-spectrum anthelmintics.

pharmacology and toxicology↗

Sequential infection with influenza A virus followed by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) leads to more severe disease and encephalitis in a mouse model of COVID-19.

COVID-19 is a spectrum of clinical symptoms in humans caused by infection with SARS-CoV-2, a recently emerged coronavirus that rapidly caused a pandemic. Coalescence of this virus with seasonal respiratory viruses, particularly influenza virus is a global health concern. To investigate this, transgenic mice expressing the human ACE2 receptor driven by the epithelial cell cytokeratin-18 gene promoter (K18-hACE2) were first infected with IAV followed by SARS-CoV-2. The host response and effect on virus biology was compared to K18-hACE2 mice infected with IAV or SARS-CoV-2 only. Infection of mice with each individual virus resulted in a disease phenotype compared to control mice. Although SARS-CoV-2 RNA synthesis appeared significantly reduced in the sequentially infected mice, they exhibited more rapid weight loss, more severe lung damage and a prolongation of the innate response compared to singly infected or control mice. The sequential infection also exacerbated the extrapulmonary encephalitic manifestations associated with SARS-CoV-2 infection. Conversely, prior infection with a commercially available, multivalent live-attenuated influenza vaccine (Fluenz tetra) elicited the same reduction in SARS-CoV-2 RNA synthesis albeit without the associated increase in disease severity. This suggests that the innate immune response stimulated by infection with IAV is responsible for the observed inhibition of SARS-CoV-2, however, infection with attenuated, apathogenic influenza vaccine does not result in an aberrant immune response and enhanced disease severity. Taken together, the data suggest that the concept of twinfection is deleterious and mitigation steps should be instituted as part of a comprehensive public health response to the COVID-19 pandemic.

microbiology↗

High dimensional analyses of cells dissociated from cryopreserved synovial tissue

BackgroundDetailed molecular analyses of cells from rheumatoid arthritis (RA) synovium hold promise in identifying cellular phenotypes that drive tissue pathology and joint damage. The Accelerating Medicines Partnership (AMP) RA/SLE network aims to deconstruct autoimmune pathology by examining cells within target tissues through multiple high-dimensional assays. Robust standardized protocols need to be developed before cellular phenotypes at a single cell level can be effectively compared across patient samples.\n\nMethodsMultiple clinical sites collected cryopreserved synovial tissue fragments from arthroplasty and synovial biopsy in a 10%-DMSO solution. Mechanical and enzymatic dissociation parameters were optimized for viable cell extraction and surface protein preservation for cell sorting and mass cytometry, as well as for reproducibility in RNA sequencing (RNA-seq). Cryopreserved synovial samples were collectively analyzed at a central processing site by a custom-designed and validated 35-marker mass cytometry panel. In parallel, each sample was flow sorted into fibroblast, T cell, B cell, and macrophage suspensions for bulk population RNA-seq and plate-based single cell CEL-Seq2 RNA-seq.\n\nResultsUpon dissociation, cryopreserved synovial tissue fragments yielded a high frequency of viable cells, comparable to samples undergoing immediate processing. Optimization of synovial tissue dissociation across six clinical collection sites with [~]30 arthroplasty and [~]20 biopsy samples yielded a consensus digestion protocol using 100{micro}g/mL of Liberase TL enzyme. This protocol yielded immune and stromal cell lineages with preserved surface markers and minimized variability across replicate RNA-seq transcriptomes. Mass cytometry analysis of cells from cryopreserved synovium distinguished: 1) diverse fibroblast phenotypes, 2) distinct populations of memory B cells and antibody-secreting cells, and 3) multiple CD4+ and CD8+ T cell activation states. Bulk RNA sequencing of sorted cell populations demonstrated robust separation of synovial lymphocytes, fibroblasts, and macrophages. Single cell RNA-seq produced transcriptomes of over 1000 genes/cell, including transcripts encoding characteristic lineage markers identified.\n\nConclusionWe have established a robust protocol to acquire viable cells from cryopreserved synovial tissue with intact transcriptomes and cell surface phenotypes. A centralized pipeline to generate multiple high-dimensional analyses of synovial tissue samples collected across a collaborative network was developed. Integrated analysis of such datasets from large patient cohorts may help define molecular heterogeneity within RA pathology and identify new therapeutic targets and biomarkers.

immunology↗

Single Cell Transcriptomics And Flow Cytometry Reveal Disease-Associated Fibroblast Subsets In Rheumatoid Arthritis

Fibroblasts mediate normal tissue matrix remodeling, but they can cause fibrosis or tissue destruction following chronic inflammation. In rheumatoid arthritis (RA), synovial fibroblasts expand, degrade cartilage, and drive joint inflammation. Little is known about fibroblast heterogeneity or if aberrations in fibroblast subsets relate to disease pathology. Here, we used an integrative strategy, including bulk transcriptomics on targeted subpopulations and unbiased single-cell transcriptomics, to analyze fibroblasts from synovial tissues. We identify 7 phenotypic fibroblast subsets with distinct surface protein phenotypes, and these collapsed into 3 subsets based on transcriptomics data. One subset expressing PDPN, THY1, but lacking CD34 was 3-fold expanded in RA relative to osteoarthritis (P=0.007); most of these cells expressed CDH11. The subsets were found to differ in expression of cytokines and matrix metalloproteinases, localization in synovial microanatomy, and in response to TNF. Our approach provides a template to identify pathogenic stromal cellular subsets in complex diseases.

immunology↗