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Buckley, C. D.

Publications and source records attributed to Buckley, C. D..

15 recordsLinked to original sources

LIF is a pro-algesic mediator in human and mouse models of arthritis-related pain

Purpose: Emerging clinical and experimental data suggest that JAK inhibitors (JAKi) are effective in reducing pain in Rheumatoid Arthritis (RA). We recently showed that JAK/STAT signalling cytokines, specifically IL-6, LIF and IL-11, are present in the RA joint and can act directly on human induced pluripotent stem cell (iPSC) derived sensory neurons by increasing their STAT3 phosphorylation (pSTAT3) levels and expression of select pain-relevant genes. In this study, we determined that LIF is the most consequential cytokine out of the three, altering neuronal signalling, outgrowth and pain-like behaviours in in vitro and in vivo models of arthritis. Methods: Human iPSC-derived sensory neurons were stimulated with RA synovial fluid (SF) or with cytokine-treated RA synovial fibroblast conditioned media (CM) in the absence or presence of anti-cytokine antibodies. pSTAT3 and pSTAT1 levels, and gene expression patterns, were assessed by Western blot and RNA-sequencing (RNA-seq). The immortalised dorsal root ganglion (DRG)-derived cell line (HD 10.6) was assessed for LIF-induced JAK/STAT signalling in addition to neurite outgrowth assays as a functional readout of the sensory neurons. Lastly, mouse models were used to assess pain-related behaviours in vivo. Results: LIF was found to be consistently present in the SF from painful joints from individuals with inflammatory arthritis. Western blotting revealed that the addition of RA SF to iPSC-derived sensory neurons led to LIF-dependent induction of pSTAT3 and pSTAT1, while RNA-seq demonstrated that LIF alters the transcriptome of sensory neurons more prominently than IL-6 and IL-11, up-regulating signature genes related to peripheral neuron sensitization, such as TRPV1, NTRK1, BDNF, HRH1 and SCN10A. Similarly, cytokine-treated fibroblast conditioned media was shown to induce neuronal pSTAT3 and pSTAT1 and upregulate expression of BDNF, HRH1 and VGF in a LIF-dependent manner. Additionally, the immortalised dorsal root ganglion (DRG)-derived cell line (HD 10.6), which also exhibited LIF-induced pSTAT1 and pSTAT3, showed increased neurite outgrowth after axotomy when treated with LIF. Finally, in a mouse model of inflammatory arthritis, LIF was shown to be significantly increased in the affected joint. Furthermore, intraarticular injection of LIF into a healthy mouse knee resulted in increased responsiveness to painful pressure stimuli in that joint. Conclusions: Our data indicate that LIF may be a pro-algesic mediator and a possible therapeutic target to improve pain management in individuals living with inflammatory arthritis.

neuroscience↗

The ontogeny of myeloid-stromal synovial tissue niches in rheumatoid arthritis.

Recent single-cell multi-omic and spatial analyses of synovial biopsies have transformed our understanding of myeloid cell-driven mechanisms underlying human joint pathology and tissue homeostasis in Rheumatoid arthritis (RA). However, the developmental trajectories of synovial tissue macrophage (STM) subsets in humans remain poorly understood, due in part to the lack of models that faithfully replicate synovial tissue niches. This hinders the exploration of the therapeutic potential of targeting specific synovial myeloid cell clusters. Using multi-omics analyses of synovial tissue from an allogeneic bone marrow transplant recipient, we show that joint-specific tissue-resident STM subsets, including both health- and disease-associated clusters, can derive from peripheral blood monocytes. Analysis of embryonic synovial joints revealed that macrophage localization and maturation in the joints are preceded by local stromal niche specialisation, indicating that synovial fibroblasts (FLS) provide tissue-specific instructive cues to STM precursors. To elucidate human STM developmental trajectories, we established a SNP-based fate-tracking human synovial organoid system by embedding distinct blood-derived myeloid precursors, together with FLS clusters from RA synovial biopsies and endothelial cells, into 3D structures. These organoids reproduced key synovial tissue features, including lining and sublining architecture and stromal-myeloid cell cluster composition. Importantly, they supported differentiation of all resident STM subsets: homeostatic lining TREM2pos macrophages, their pathogenic TREM2lowSPP1pos counterparts that characterize the RA hyperplastic lining, and both homeostatic and RA-associated perivascular LYVE1pos STM clusters, all traced to monocytic precursors. In summary, we show that development of STM subsets is driven by fibroblast-conditioned spatial niches. We have established a novel, tractable ex vivo platform to dissect the niche-specific cues driving homeostatic versus pathogenic phenotypic clusters. One Sentence SummaryHuman tissue-resident STMs develop from monocytes under the guidance of cues from FLS within discrete spatial locations.

immunology↗

An end-to-end framework for Cell DIVE multiplexed imaging and spatial immune microenvironment analysis

This paper describes an end-to-end workflow for highly multiplexed fluorescence imaging with the Cell DIVE platform, allowing simultaneous detection of 40+ markers at single-cell resolution. Combining whole-slide multiplexed imaging with a dedicated analysis pipeline provides a powerful approach to investigate immune cell interactions with stromal and vascular networks within human tissue microenvironments. With a focus on spatial investigation of human immune niches, here we provide a complete framework for tissue preparation, autofluorescence reduction, multiplex panel design and whole-slide image analysis. For complete details on the use and execution of this protocol, please refer to Korsunsky et al. (Med, 2022) [1]. HighlightsO_LIComplete workflow for Cell DIVE multiplex imaging and quantitative image analysis. C_LIO_LIHuman FFPE tissue preparation, LED-based reduction of tissue autofluorescence. C_LIO_LIAntibody panel design for 3-40 marker multiplexing, in-house antibody conjugation. C_LIO_LIQuPath and DeepCell based analysis workflows for whole-slide multi-marker images. C_LIO_LIAdaptable code templates to accelerate cell segmentation and spatial niche analysis. C_LI Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=113 SRC="FIGDIR/small/656440v1_ufig1.gif" ALT="Figure 1"> View larger version (42K): org.highwire.dtl.DTLVardef@1ef708dorg.highwire.dtl.DTLVardef@c6422dorg.highwire.dtl.DTLVardef@22d961org.highwire.dtl.DTLVardef@1ed7479_HPS_FORMAT_FIGEXP M_FIG C_FIG

immunology↗

Cellular and molecular landscapes of human tendons across the lifespan revealed by spatial and single-cell transcriptomics

Tendon injuries are common and often heal poorly. While developing tendons heal without scarring, this capacity declines with age, yet the underlying cellular transitions remain poorly defined. Here, we integrate histological, single-nucleus, single-cell, and spatial transcriptomic profiling of human Achilles and quadriceps tendons across embryonic, foetal, and adult stages, including ruptured adult tendons. We identify seven embryonic progenitor states that give rise to three distinct tendon-associated fibrillar, connective tissue, and chondrogenic lineages. These populations diversify during development and occupy distinct spatial niches, adopting specialised roles in matrix synthesis, tissue remodelling, and mechanical adaptation. While non-fibroblast populations remain transcriptionally stable with age, fibroblasts undergo marked reprogramming, shifting to homeostatic or injury-responsive states. In ruptured adult tendons, a subset of fibroblasts partially reactivates developmental programs but remains transcriptionally distinct from their regenerative counterparts. These findings define the cellular architecture of human tendon development and ageing and reveal lineage-specific targets for therapeutic repair.

cell biology↗

Tissue resident memory T cells populate the human uveal tract

The current concept is that the eye is an immune privileged site endowed with innate immune regulatory networks to maintain organ function. We now have evidence that resident T cells occupy intraocular tissues. In immune-mediated inflammatory diseases, such as psoriasis and rheumatoid arthritis, tissue resident T cells trigger disease flares in the skin and joints. This suggests resident T cells in the uvea may have similar functions in non-infectious immune-mediated uveitis, a collective term for autoinflammatory and autoimmune diseases of the uveal tract causing intraocular inflammation. Here, we demonstrate by spectral cytometry and immunofluorescence imaging that non-inflamed uveal tissue contains multiple T cell subtypes including CD8+ CD103+ tissue resident memory T (TRM) cells. Using single cell RNA & T cell receptor (TCR) sequencing to profile aqueous humour cells from donors with acute, active uveitis, we identify clonally expanded T cells which are enriched for TRM -associated genes. We further show that in donors with active uveitis, CD8+ CD103+ T cells persist within tissue in the uveal tract. Using bulk RNA sequencing and weighted gene co-expression network analysis (WGCNA) we show that quiescent iris tissue from donors with a history of uveitis are enriched for genes associated with T cell activation and antigen presentation. Finally, we demonstrate that TRM cells persist in the anterior uvea in mice following resolution of experimental autoimmune uveoretinitis (EAU). Our results show that the human eye contains T cells both in health and during active inflammation. Our findings challenge the dogma that the eye is devoid of lymphocytes and supports the concept of resident T cell involvement in the pathogenesis of non-infectious immune-mediated uveitis and as promising targets for therapy. One Sentence SummaryT cells infiltrate aqueous humour during intraocular inflammation and have capacity to migrate into uveal tissue where they remain long-lived.

immunology↗

Wnt signaling drives stromal inflammation in inflammatory arthritis

The concept that fibroblasts are critical mediators of inflammation is an emerging paradigm. In rheumatoid arthritis (RA), they are the main producers of IL-6 as well as a host of other cytokines and chemokines. Their pathologic activation also directly causes cartilage and bone degradation. Yet, therapeutic agents specifically targeting fibroblasts are not available. Here, we find that Wnt receptors and modulators are predominantly expressed in stromal populations in the synovium. Importantly, non-canonical Wnt activation induces robust inflammatory gene expression including an abundance of cytokines and chemokines in synovial fibroblasts in vitro. Strikingly, the addition of Wnt ligands or inhibition of Wnt secretion exacerbates or reduces arthritis severity, respectively, in vivo in a murine model of inflammatory arthritis. These observations are relevant in human disease, as Wnt activation signatures are enhanced in fibroblasts derived from inflamed RA synovial tissue as well as fibroblasts across other inflammatory diseases. Together, these findings implicate Wnt signaling as a major driver of fibroblast-mediated inflammation and joint pathology. They further suggest that targeting the Wnt pathway is a therapeutically relevant approach to rheumatoid arthritis, particularly in patients who do not respond to conventional treatments and who often express fibroblast-predominant synovial phenotypes.

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 multiomic atlas of human early skeletal development

Bone and joint formation in the developing skeleton rely on co-ordinated differentiation of progenitors in the nascent developing limbs and joints. The cell states, epigenetic processes and key regulatory factors underlying their lineage commitment to osteogenic and other mesenchymal populations during ossification and joint formation remain poorly understood and are largely unexplored in human studies. Here, we apply paired single-nuclei transcriptional and epigenetic profiling of 336,000 droplets, in addition to spatial transcriptomics, to construct a comprehensive atlas of human bone, cartilage and joint development in the shoulder, hip, knee and cranium from 5 to 11 post-conception weeks. Spatial mapping of cell clusters to our highly multiplexed in situ sequencing (ISS) data using our newly developed tool ISS-Patcher revealed new cellular mechanisms of zonation during bone and joint formation. Combined modelling of chromatin accessibility and RNA expression allowed the identification of the transcriptional and epigenetic regulatory landscapes that drive differentiation of mesenchymal lineages including osteogenic and chondrogenic lineages, and novel chondrocyte cell states. In particular, we define regionally distinct limb and cranial osteoprogenitor populations and trajectories across the fetal skeleton and characterise differential regulatory networks that govern intramembranous and endochondral ossification. We also introduce SNP2Cell, a tool to link cell-type specific regulatory networks to numerous polygenic traits such as osteoarthritis. We also conduct in silico perturbations of genes that cause monogenic craniosynostosis and implicate potential pathogenic cell states and disease mechanisms involved. This work forms a detailed and dynamic regulatory atlas of human fetal skeletal maturation and advances our fundamental understanding of cell fate determination in human skeletal development.

developmental biology↗

IL-23 drives uveitis by acting on a novel population of tissue-resident entheseal T cells

Recurrent acute anterior uveitis is a frequent extra-articular manifestation of the axial spondyloarthropathies (AxSpA); chronic inflammatory diseases affecting the spine, enthesis, peripheral joints, skin, and gastrointestinal tract. Pathology in AxSpA has been associated with local tissue-resident populations of interleukin (IL)-23 responsive lymphoid cells. Here we reveal a novel population of ocular T cells defined by CD3+CD4-CD8-{gamma}{delta}TCR+IL-23R+ that reside within the anterior uvea as an ocular entheseal analogue of the mouse eye. Localised cytokine expression demonstrates that uveal IL-23R+ IL-17A-producing cells are both necessary and sufficient to drive uveitis in response to IL-23. This T cell population is also present in humans, occupying extravascular tissues of the anterior uveal compartment. Consistent with the concept of IL-23 as a unifying mediator in AxSpA, we present evidence that IL-23 can also act locally on tissue resident T cells in the anterior compartment of the eye at sites analogous to the enthesis to drive ocular inflammation.

immunology↗

Primed to resolve: A single cell atlas of the shoulder capsule reveals a cellular basis for resolving inflammatory fibrosis

Fibrotic conditions are a significant global disease burden. While some therapies delay disease progression, none reverse fibrosis. To gain insights into how fibrosis might resolve, we developed a comparative single cell atlas of frozen shoulder capsule tissue; a chronic inflammatory fibrotic human disease that resolves spontaneously. We identified both a population of pro-inflammatory MERTKlowCD48+ macrophages (M{varphi}) and a population of MERTK+LYVE1+MRC1+M{varphi} enriched for negative regulators of inflammation. Micro-cultures of patient-derived cells identified cell-matrix interactions between MERTK+M{varphi} and DKK3+ and POSTN+ fibroblasts, suggesting that matrix remodelling plays a role in the resolution of frozen shoulder. Cross-tissue analysis revealed a shared gene expression cassette between MERTK+M{varphi} in the shoulder capsule and a similar cell population enriched in synovial tissues from rheumatoid arthritis patients in disease remi ssion, supporting the concept that MERTK+M{varphi} provide a cellular basis for the resolution of inflammation and fibrosis. Single-cell transcriptomic profiling and spatial analysis of human foetal shoulder tissues identified MERTK+LYVE1+MRC1+M{varphi} and DKK3+ and POSTN+ fibroblast populations analogous to those identified in adult shoulder capsule, suggesting that the template to resolve fibrosis is established during development. Therapeutic enhancement of crosstalk between MerTK+M{varphi} and pro-resolving DKK3+ and POSTN+ fibroblasts could accelerate resolution of frozen shoulder and resolve persistent inflammatory fibrotic disease in other tissues.

cell biology↗

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↗

Cross-tissue, single-cell stromal atlas identifies shared pathological fibroblast phenotypes in four chronic inflammatory diseases

Pro-inflammatory fibroblasts are critical to pathogenesis in rheumatoid arthritis, inflammatory bowel disease, interstitial lung disease, and Sjogrens syndrome, and represent a novel therapeutic target for chronic inflammatory disease. However, the heterogeneity of fibroblast phenotypes, exacerbated by the lack of a common cross-tissue taxonomy, has limited the understanding of which pathways are shared by multiple diseases. To investigate, we profiled patient-derived fibroblasts from inflamed and non-inflamed synovium, intestine, lung, and salivary glands with single-cell RNA-sequencing. We integrated all fibroblasts into a multi-tissue atlas to characterize shared and tissue-specific phenotypes. Two shared clusters, CXCL10+CCL19+ immune-interacting and SPARC+COL3A1+ vascular-interacting fibroblasts were expanded in all inflamed tissues and additionally mapped to dermal analogues in a public atopic dermatitis atlas. We further confirmed these human pro-inflammatory fibroblasts in animal models of lung, joint, and intestinal inflammation. This work represents the first cross-tissue, single-cell fibroblast atlas revealing shared pathogenic activation states across four chronic inflammatory diseases.

genomics↗

Loss of α2-6 sialylation promotes the transformation of synovial fibroblasts into a pro-inflammatory phenotype in Rheumatoid Arthritis.

In healthy joints, synovial fibroblasts (SFs) provide the microenvironment required to mediate homeostasis but are recognized to adopt a pathological role in rheumatoid arthritis (RA), promoting the infiltration and activation of immune cells to perpetuate local inflammation, pain and joint destruction. Carbohydrates (glycans) attached to cell surface proteins are fundamental regulators of cellular interactions between stromal and immune cells, but very little is known about the glycome of SFs or how glycosylation regulates their biology. Here we fill these gaps in our understanding of stromal guided pathophysiology by systematically mapping glycosylation pathways in healthy and arthritic SFs. We used a combination of transcriptomic and glycomic analysis to show that transformation of fibroblasts into pro-inflammatory cells in RA is associated with profound glycan remodeling, a process that involves reduction of 2-6 terminal sialylation that is mostly mediated by TNF-dependent inhibition of the glycosyltransferase ST6Gal1. We also show that sialylation of SFs correlates with distinct disease stages and SFs functional subsets in both human RA and models of mouse arthritis. We propose that pro-inflammatory cytokines in the joint remodel the SF-glycome, transforming a regulatory tissue intended to preserve local homeostasis, into an under-sialylated and highly pro-inflammatory microenvironment that contributes to an amplificatory inflammatory network that perpetuates chronic inflammation. These results highlight the importance of cell glycosylation in stromal immunology.

immunology↗

Pathologically distinct fibroblast subsets drive inflammation and tissue damage in arthritis

The identification of lymphocyte subsets with non-overlapping effector functions has been pivotal to the development of targeted therapies in immune mediated inflammatory diseases (IMIDs). However it remains unclear whether fibroblast subclasses with non-overlapping functions also exist and are responsible for the wide variety of tissue driven processes observed in IMIDs such as inflammation and damage. Here we identify and describe the biology of distinct subsets of fibroblasts responsible for mediating either inflammation or tissue damage in arthritis. We show that deletion of FAP+ synovial cells suppressed both inflammation and bone erosions in murine models of resolving and persistent arthritis. Single cell transcriptional analysis identified two distinct fibroblast subsets: FAP+ THY1+ immune effector fibroblasts located in the synovial sub-lining, and FAP+ THY1- destructive fibroblasts restricted to the synovial lining. When adoptively transferred into the joint, FAP + THY1- fibroblasts selectively mediate bone and cartilage damage with little effect on inflammation whereas transfer of FAP + THY1+ fibroblasts resulted in a more severe and persistent inflammatory arthritis, with minimal effect on bone and cartilage. Our findings describing anatomically discrete, functionally distinct fibroblast subsets with non-overlapping functions have important implications for cell based therapies aimed at modulating inflammation and tissue damage.

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↗