Biology subjects

Gilroy, D.

Publications and source records attributed to Gilroy, D..

7 recordsLinked to original sources

bioRxiv2026

Elevated ferritin as a companion biomarker of myeloid-driven inflammation in RNP/Sm co-positive, treatment-resistant SLE endotype

BackgroundThe profound molecular heterogeneity of SLE remains a fundamental barrier to therapeutic progress. MethodsWe integrated clinical and multi-omic profiling, including transcriptomics, autoantigen microarrays, proteomics, and flow cytometry, across three randomised trials (BEAT-Lupus, CALIBRATE, ACCESS) and two observational cohorts to identify distinct lupus endotypes. FindingsUsing multivariate distance-based matching of autoantibody profiles to integrate molecular heterogeneity, we identified anti-RNP/anti-Sm co-positivity (RNP+Sm+) as a distinct myeloid-dominant inflammatory endotype. Enriched in patients of Black ancestry (approx. 50%), RNP+Sm+ SLE is characterised by expanded intermediate monocytes showing enhanced TLR4-driven inflammation during flares, elevated pro-inflammatory cytokines (TNF-alpha, IL-6, IL-12, IFN-gamma, CCL2), IFNA10-biased interferon signalling, and systemic metabolic activation. IgG autoantibody profiling confirmed epitope spreading to spliceosomes and novel autoreactivity against circadian-metabolic regulators (SIRT1, NCOA1, SREBF1). Clinically, this endotype manifests as high-grade disease activity (2.5-fold flare risk), nephritis, vasculitis, and enteritis. Hyperferritinaemia correlates with flares exclusively in RNP+Sm+ SLE (r=0.81), reflecting underlying macrophage activation. RNP+Sm+ patients exhibit profound therapeutic resistance: 44% failed first-line immunosuppression (rising to 61% in Black patients), while also showing substantially reduced efficacy (60% lower response) with second-line B-cell-depleting therapies (rituximab, obinutuzumab). Resistance to rituximab therapy was driven by rapid B-cell repopulation, rising BAFF levels, and sustained cytokines despite peripheral depletion. Consequently, they remain heavily steroid-dependent and accrued greater organ damage. ConclusionThe RNP+Sm+ signature defines a high-risk, refractory, myeloid-driven lupus endotype characterised by activity linked hyperferritinemia that likely requires therapies directed at the underlying interferon and myeloid-centred pathways. FundingBEAT-Lupus: Arthritis UK and GSK. ACCESS and CALIBRATE: National Institute of Allergy and Infectious Diseases of the NIH. Context and SignificanceSystemic lupus erythematosus (SLE) is immunologically heterogeneous, yet conventional classifications fail to predict therapeutic outcomes. While autoantibodies are central to diagnosis, whether specific combinations define mechanistically distinct subsets remains unresolved. Here, we demonstrate that anti-RNP/anti-Sm co-positivity (RNPSm) identifies a clinically aggressive, myeloid-dominant endotype disproportionately affecting Black patients. Multi-omics integration revealed expansion of intermediate monocytes with enhanced TLR4 expression, IFNA10-biased interferon signalling, and metabolic reprogramming. Clinically, RNPSm patients exhibit nephritis, vasculitis, higher flare rates, and profound first-line therapeutic resistance. Subsequently, this endotype shows poor response to B-cell-depleting therapies, necessitating prolonged glucocorticoid dependence and accelerated organ damage. Establishing RNPSm as a lupus endotype and ferritin as a companion disease activity biomarker enables precision stratification and highlights an underserved, high-risk population requiring urgent development of alternative strategies like myeloid-targeted and interferon-directed therapies. HighlightsO_LIAnti-RNP/Sm co-positivity defines a high-risk, flare-prone, myeloid-dominant SLE endotype C_LIO_LIRNPSm patients, especially Black patients, show profound refractoriness to first-line and B-cell depletion therapies C_LIO_LIExpanded intermediate monocytes with TLR4 upregulation and IFNA10-biased interferon signalling C_LIO_LIHyperferritinaemia correlates with disease activity exclusively in RNPSm patients C_LI

immunology↗

bioRxiv2024

Cardiovascular symptoms of PASC are associated with trace-level cytokines that affect the function of human pluripotent stem cell derived cardiomyocytes

Globally, over 65 million individuals are estimated to suffer from post-acute sequelae of COVID-19 (PASC). A large number of individuals living with PASC experience cardiovascular symptoms (i.e. chest pain and heart palpitations) (PASC-CVS). The role of chronic inflammation in these symptoms, in particular in individuals with symptoms persisting for >1 year after SARS-CoV-2 infection, remains to be clearly defined. In this cross-sectional study, blood samples were obtained from three different sites in Australia from individuals with i) a resolved SARS-CoV-2 infection (and no persistent symptoms i.e. Recovered), ii) individuals with prolonged PASC-CVS and iii) SARS-CoV-2 negative individuals. Individuals with PASC-CVS, relative to Recovered individuals, had a blood transcriptomic signature associated with inflammation. This was accompanied by elevated levels of pro-inflammatory cytokines (IL-12, IL-1{beta}, MCP-1 and IL-6) at approximately 18 months post-infection. These cytokines were present in trace amounts, such that they could only be detected with the use of novel nanotechnology. Importantly, these trace-level cytokines had a direct effect on the functionality of pluripotent stem cell derived cardiomyocytes in vitro. This effect was not observed in the presence of dexamethasone. Plasma proteomics demonstrated further differences between PASC-CVS and Recovered patients at approximately 18 months post-infection including enrichment of complement and coagulation associated proteins in those with prolonged cardiovascular symptoms. Together, these data provide a new insight into the role of chronic inflammation in PASC-CVS and present nanotechnology as a possible novel diagnostic approach for the condition.

microbiology↗

bioRxiv2023

Re-analysis of lipidomic data reveals Specialised Pro-Resolution Lipid Mediators (SPMs) to be lower than quantifiable limits of assay in a human model of resolving inflammation.

Using a model of UV-killed E. coli driven dermal inflammation in healthy human volunteers we originally reported that following inflammatory resolution there was the infiltration of macrophages, which, through prostanoids including prostaglandin (PG)E2, imprints long-term tissue immunity. In addition to the prostanoids, we also presented data on levels of Specialised Pro-Resolution Lipid Mediators (SPMs) throughout inflammatory onset, resolution and post-resolution phases of this model. However, our collaborators who carried out the lipidomic analysis received a complaint concerning how they generally present SPM data in their publications, namely their use of graphical illustrations to depict data. Importantly, such lipidomic illustrations were used in our human UV-killed E. coli study. Therefore, in the interest of transparency and to replace these illustrations with more meaningful images, the original data from our human UV-killed E. coli model were re-analysed by two independent experts. It transpires that the integrated areas of the chromatographic peaks of the SPM lipid mediators were below the amounts that could be reliably either detected and/or quantified using community standards for quantitation. Here we show the outcome of this reanalysis. Importantly, with prostanoids including PGE2 being robustly detected, this re-analysis does not alter the original report that post-resolution PGs imprint tissue immunity.

immunology↗

bioRxiv2023

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↗

bioRxiv2022

Neutrophils infiltrate sensory ganglia and mediate chronic widespread pain in fibromyalgia

Fibromyalgia is a debilitating widespread chronic pain syndrome that occurs in 2-4% of the population. The prevailing view that fibromyalgia results from central nervous system dysfunction has recently been challenged with data showing changes in peripheral nervous system activity. Using a mouse model of chronic widespread pain through hyperalgesic priming of muscle, we show that neutrophils invade sensory ganglia and confer mechanical hypersensitivity on recipient mice, whilst adoptive transfer of immunoglobulin, serum, lymphocytes or monocytes have no effect on pain behaviour. Neutrophil depletion abolishes the establishment of chronic widespread pain in mice. Neutrophils from patients with fibromyalgia also confer pain on mice. A link between neutrophil derived mediators and peripheral nerve sensitisation is already established. These observations suggest new approaches for targeting fibromyalgia pain through an understanding of the mechanisms that cause altered neutrophil activity and interactions with sensory neurons. Significance statementWe used a back-translational model in mice to demonstrate the pro-nociceptive role of neutrophils in fibromyalgia. Adoptive transfer of neutrophils from mice with chronic widespread pain or from patients with fibromyalgia can confer mechanical pain to recipient naive mice, sensitise evoked action potential firing of spinal cord neurons and produce phenotypic changes in cell surface expression of neutrophil proteins that cause infiltration of neutrophils into dorsal root ganglia. These data provide the framework for an immunological basis of chronic widespread pain in fibromyalgia mediated by polymorphonuclear granulocytes.

neuroscience↗

bioRxiv2020

Intercellular telomere transfer extends T cell lifespan

The common view is that T-lymphocytes activate telomerase, a DNA polymerase that extends telomeres at chromosome ends, to delay senescence. We show that independently of telomerase, T cells elongate telomeres by acquiring telomere vesicles from antigen-presenting cells (APCs). Upon contact with T cells, APCs degraded shelterin to donate telomeres, which were cleaved by TZAP, and then transferred in extracellular vesicles (EVs) at the immunological synapse. Telomere vesicles retained the Rad51 recombination factor that enabled them to fuse with T cell chromosomal ends causing an average lengthening of [~]3000 base pairs. Thus, we identify a previously unknown telomere transfer program that supports T cell lifespan.

immunology↗

bioRxiv2020

Monocyte-derived Prostaglandin E2 inhibits antigen-specific cutaneous immunity during ageing

Ageing results in a decline in immune function. We showed previously that healthy older humans (>65 years old) have reduced antigen-specific cutaneous immunity to varicella zoster virus (VZV) antigen challenge. This was associated with p38 MAP kinase driven inflammation that was induced by mild tissue injury caused by the injection of the antigen itself. Here we show that non-specific injury induced by injection of air or saline into the skin of older adults recruits CCR2+CD14+ monocytes by CCL2 produced by senescent fibroblasts. These monocytes reduced TRM proliferation via secretion of prostaglandin E2 (PGE2). Pre-treatment with a p38-MAPK inhibitor (Losmapimod) in older adults in vivo significantly decreased CCL2 expression, recruitment of monocyte into the skin, COX2 expression and PGE2 production. This enhanced the VZV response in the skin. Therefore, local inflammation arising from interaction between senescent cells and monocytes leads to immune decline in the skin during ageing, a process that can be reversed. SummaryInflammation resulting from tissue injury blocks antigen-specific cutaneous immunity during ageing. Monocytes recruited to the skin inhibit TRM function through COX2-derived prostaglandin E2 production. Blocking inflammation and resulting prostaglandin E2 production with a p38-MAP kinase inhibitor significantly enhances cutaneous antigen-specific responses.

immunology↗