Interleukin-1 Receptor Research Articles

The Causal Relationships and Therapeutic Targets of Plasma Proteins in Ankylosing Spondylitis

Objective: The purpose of this study was to assess the causal effects of circulating plasma proteins on ankylosing spondylitis (AS) and to explore potential therapeutic targets. Methods: The study used protein quantitative trait loci (pQTLs) for thousands of plasma proteins from nine genome-wide association studies (GWAS) as instrumental variables. The relationship between genetically predicted plasma proteins and AS was assessed through Mendelian randomization (MR) analysis. Further analyses, including colocalization analysis, Steiger filtering analysis, protein-altering variant assessment, protein–protein interaction (PPI), and pathway enrichment analysis, were conducted to validate the robustness and causal direction of the results, as well as to investigate the protein functions and potential drug targets. Results: Nine unique proteins were found to have strong causal associations with AS. Steiger filtering analysis confirmed that all associations identified by MR analysis have a direct causal link from the proteins to AS. Colocalization analysis identified four unique proteins—Interleukin-6 receptor alpha (IL-6Rα), Interleukin-23 receptor (IL-23R), Thrombospondin-2 (THBS2), and Interleukin-1 receptor type 2 (IL-1R2)—that share the same causal variants with AS. PPI and pathway enrichment analysis revealed the potential roles of these proteins in inflammatory responses and immune regulation. Moreover, these proteins were valuable drug targets or considered druggable. Conclusions: This study has identified multiple plasma proteins associated with AS, revealing the important roles of these proteins in the pathogenesis of AS and providing potential therapeutic targets for AS.

Role of interleukin-4 receptor α polymorphism in patients with asthma and its correlation with asthma severity

Asthma is a heterogeneous disease characterized by chronic airway inflammation. It is defined by the history of respiratory symptoms such as wheeze, shortness of breath, chest tightness, and cough that vary over time and intensity, together with variable expiratory airflow limitation. A personal history or a family history of allergy is the factor most strongly associated with the development of asthma. Our primary aim was to investigate interleukin-4 receptor α (IL-4Rα) polymorphism to determine whether the presence of the R576 IL-4Rα allele was associated with asthma and whether the presence of the R576 allele influenced the severity of asthma in affected individuals. The data obtained indicated asthmatic patients were characterized by a higher prevalence of positive family history of asthma (p<0.001) as compared to controls. It was found that the patients homozygous for mutant alleles had a 1.39-fold increased risk of asthma compared with individuals not homozygous for R576. Also, we found that females had higher odds (1.61-fold) of significant association with asthma (p=0.09; odds ratio=1.58). While this report clearly necessitates a more detailed study, it is plausible that IL-4 mutation has a significant role in the development of asthma and, thus, can play an important role in developing targeted therapy.

Distinct single cell transcriptional profile in CD4+ T-lymphocytes among obese children with asthma.

Introduction: Obesity is a risk factor for asthma morbidity, associated with less responsiveness to inhaled corticosteroids. CD4+ T-cells are central to the immunology of asthma and may contribute to the unique obese asthma phenotype. We sought to characterize the single cell CD4+ Transcriptional profile differences in obese children with asthma compared to normal weight children with asthma. Methods: Eight normal weight and obese participants with asthma were clinically phenotyped and matched based on asthma control. Peripheral blood (PB) CD4+ T-cells were sorted, and single cell RNA sequencing was conducted. Cell clusters were identified by canonical gene expression, differential gene expression and reactome pathway analysis was applied. The obese PB bulk transcriptomic signature from the U-BIOPRED pediatric cohort was assessed in our cohort as well. Results: Obese children with asthma have a distinct CD4+ transcriptional profile with differential gene expression. There were more activated protein tyrosine phosphate receptor type C (PTPRC)high cells and less PTPRClow in the obese children. Obese children had higher enrichment of the neutrophil degranulation, interleukin-7 (IL-7) receptor and IL-7-related janus kinase-signal transducer and activator of transcription signaling pathways. Genes previously associated with more severe asthma, IL-32, FKBP5 gene expression, IL-6 and Rho transcriptional signaling, were also enriched in obese children with asthma. Discussion: Our findings shed insight into the molecular mechanisms underpinning more severe and steroid-resistant asthma among obese children. Further investigation is needed to identify potential new therapeutic targets for this group.

Ouabain Counteracts Retinal Ganglion Cell Death Through Modulation of BDNF and IL-1 Signaling Pathways

Background: Ouabain is a steroid hormone that binds to the sodium pump (Na+, K+-ATPase) at physiological (nanomolar) concentrations, activating different signaling pathways. This interaction has been shown to prevent the axotomy-induced death of retinal ganglion cells (RGCs), although the underlying mechanisms remain unclear. Objective: In this study, we investigated potential mechanisms by which ouabain promotes RGC survival using primary cultures of rat neural retina. Results: Our findings indicate that ouabain regulates brain-derived neurotrophic factor (BDNF) signaling in retinal cells via matrix metalloproteinase-9-mediated processing of proBDNF to mature BDNF (mBDNF) and by increasing the phosphorylation of the mBDNF receptor, tropomyosin-related receptor kinase B. Ouabain also enhances the maturation of interleukin (IL)-1β through the increased activation of caspase-1, which mediates the processing of proIL-1β into IL-1β, and transiently upregulates both IL-1 receptor and IL-1 receptor antagonist (IL-1Ra). Treatment using either IL-1β or IL-1Ra alone is sufficient to enhance RGC survival similarly to that achieved with ouabain. Finally, we further show that ouabain prevents RGC death through a complex signaling mechanism shared by BDNF and IL-1β, which includes the activation of the Src and protein kinase C pathways. Conclusions: Collectively, these results suggest that ouabain stimulates the maturation and signaling of both BDNF and IL-1β, which act as key mediators of RGC survival.

Rhanterium Epapposum Essential Oil and Its Primary Compounds Control Infection, Inflammation, and Serum Electrolyte Imbalance in Mice with Giardiasis.

The present experimental study seeks to evaluate the in vitro and in vivo effects, as well as the potential mechanisms of action, of Rhanterium epapposum essential oil (REE) and its main constituents against Giardia lamblia infection. The analysis of REE was performed using the Gas Chromatography-Mass Spectrometry (GC-MS) detector. The in vitro effects of REE and its main constituents on viability of G. lamblia cysts and the human intestinal epithelial cell line, as well as their effects on plasma membrane permeability, the reactive oxygen species (ROS) generation, and trophozoite adherence were assessed by MTT assay. Effects of oral administration of REE and its main constituents at doses 10 and 20mg/kg on the number of Giardia cysts, the serum level of electrolytes of sodium (Na+) and potassium (K+), as well as the gene expression of inflammatory genes of TNF-α, IL-1β, IL-10, NF-κB p65, and Toll-like receptor 4 (TLR4)) were assessed. The 50% inhibitory concentrations (IC50) value of REE, MC, CP, LN and MTZ against G. lamblia cysts was 26.7, 32.1, 35.3, 45.1, and 42.1µg/mL, respectively; indicated that REE, MC, and CP displayed high antigiardial effects in comparison with MTZ. The obtained 50% cytotoxic concentration (CC50) value of REE, MC, CP, LN, and MTZ on HIEC-6 cells was 279.1, 363.4, 394.2, 478.3, and 422.1µg/mL, respectively. REE and its main compounds significantly (p < 0.001) increased the plasma membrane permeability and ROS generation in Giardia trophozoites, while, reduced the Giardia trophozoites adherence. In vivo, REE, MC, CP, and LN mainly at the dose of 20mg/kg considerably reduced the number and viability of Giardia cysts, modulated the serum level of electrolytes Na and K in the infected mice compared with the mice treated with MTZ (P < 0.01); whereas inhibited the inflammation cytokines in the infected mice compared with the mice treated with MTZ (p < 0.001). The current investigation showed that R. epapposum essential oil and its main compounds controlled the Giardia infection in mice by inhibiting inflammation, and serum electrolyte imbalance. After confirmation in further studies, these compounds may be considered for development as a novel therapeutic option for the treatment of giardiasis.

A review of cutting-edge biomarkers for diagnosing coronary artery disease.

Chronic coronary artery disease (CAD) remains a significant global healthcare burden. Current risk assessment methods have notable limitations in early detection and risk stratification. Hence, there is an urgent need for innovative biomarkers that facilitate the premature CAD diagnosis, ultimately leading to reduction in associated morbidity and mortality rates. This review comprehensively examines recent advances in emerging biomarkers for CAD detection. Our analysis delves into various aspects of these biomarkers such as their mechanisms of action, roles in the pathophysiology of the disease, and different measurement techniques employed in clinical practice. Comparative assessment of biomarker performance between CAD patients and control groups was also presented relying on their sensitivity, specificity, and area under the curve at specific cutoff points. In this regard, prominent biomarkers including Tenascin-C, IL-37, PTX3, transthyretin, soluble interleukin-6 receptor α, and miR-15a are identified as having high diagnostic potential for chronic CAD that indeed showcase promising performance metrics. These findings underscore the role of novel biomarkers in enhancing CAD risk stratification and improving patient outcomes through early intervention. However, the pursuit of an ideal and inclusive biomarker continues due to the multifaceted nature of CAD. Future randomized controlled trials are essential to bridge the gap between research findings and clinical practice in order to augment the practical application of these biomarkers in routine healthcare settings.

Targeting p21-Positive Senescent Chondrocytes via IL-6R/JAK2 Inhibition to Alleviate Osteoarthritis.

Osteoarthritis (OA) is an age-related degenerative joint disease, prominently influenced by the pro-inflammatory cytokine interleukin-6 (IL-6). Although elevated IL-6 levels in joint fluid are well-documented, the uneven cartilage degeneration observed in knee OA patients suggests additional underlying mechanisms. This study investigates the role of interleukin-6 receptor (IL-6R) in mediating IL-6 signaling and its contribution to OA progression. Here, significantly elevated IL-6R expression is identified in degenerated cartilage of OA patients. Further, in vivo experiments reveal that intra-articular injection of recombinant IL-6R protein or activation of gp130 (Y757F mutation) accelerates OA progression. Conversely, knockout of IL-6R or JAK2, as well as treatment with a JAK inhibitor, alleviates OA symptoms. Mechanistically, chondrocytes derived from degenerative cartilage exhibit impaired nuclear localization of SOX9, a key regulator of cartilage homeostasis. JAK inhibition stabilizes SIRT1, reduces SOX9 acetylation, and thereby facilitates SOX9 nuclear localization, promoting cartilage repair. Additionally, the JAK inhibitor-induced apoptosis in p21-positive senescent cells, and their targeted clearance successfully alleviates OA in p21-3MR mice. In conclusion, these findings reveal a novel mechanism by which inhibiting the IL-6R/JAK2 pathway can alleviate OA. Furthermore, this study proposes targeting p21-positive senescent cells as a new therapeutic strategy for OA.

Defining a novel DYRK1A-gp130/IL-6R-pSTAT axis that regulates Th17 differentiation.

Dysregulated differentiation of naïve CD4+ T cells into T helper 17 (Th17) cells is likely a key factor predisposing to many autoimmune diseases. Therefore, better understanding how Th17 differentiation is regulated is essential to identify novel therapeutic targets and strategies to identify individuals at high risk of developing autoimmunity. Here, we extend our prior work using chemical inhibitors to provide mechanistic insight into a novel regulator of Th17 differentiation, the kinase dual-specificity tyrosine phosphorylation-regulated kinase 1A (DYRK1A). We generated a conditional knockout mouse model to validate DYRK1A as a regulator of Th17 differentiation that acts in a dose-dependent fashion at least in part by modulating interleukin (IL)-6 signaling through multiple mechanisms. We identified a new role for DYRK1A in regulating surface expression of IL-6 receptor subunits in naïve CD4+ T cells, consistent with DYRK1A's impact on Th17 differentiation. Physiologic relevance is supported by findings in people with Down syndrome, in which increased expression of DYRK1A, encoded on chromosome 21, is linked to increased IL-6 responsiveness. Our findings highlight DYRK1A as a druggable target of broad therapeutic and prognostic interest in autoimmunity and immune function.

P0172 In silico drug repurposing approach for the discovery of therapeutics for intestinal fibrosis in crohn’s disease

Abstract Background Intestinal fibrosis in Crohn’s disease (CD) can lead to stricture formation and other disease-related complications.1,2 Given the lack of anti-fibrotic drugs, current treatment strategies are limited to anti-inflammatory therapies, endoscopic balloon dilation and surgery.1 Our aim was to identify compounds and druggable targets that can reverse the gene expression signature in mucosal fibroblasts associated with intestinal fibrosis. Methods A signature associated with fibrotic CD was derived from three publicly available transcriptomic datasets of fibroblasts isolated from fibrostenotic strictures of CD patients. We conducted a meta-regression analysis across the transcriptomic datasets to identify significant differentially expressed genes (DEGs) associated with fibrostenotic CD. Three drug repurposing platforms (iLINCS, L1000 CDS2 and CLUE io), connected to the NIH LINCS database,3,4 were used to identify compounds that could reverse the fibrotic signature, ranked by their anti-fibrotic potential using the CoDReS (Composite Drug Reranking Scoring) tool. Transcription factors and miRNAs targeting the fibrostenotic signature were identified via the TRRUST and miRWalk databases. A gene interaction network was constructed, incorporating transcription factors (TRRUST TF), miRNAs and DEGs. Drugs targeting key network components were identified using the DGiDb database. Results Via the analysis of combined transcriptomic datasets from fibrostenotic- versus non-stenosis-associated mucosal fibroblasts, fibroblast activation protein (FAP), IL7 receptor and transcription factor AP-2 gamma, emerged as the most significantly upregulated genes in fibrostenotic CD (Figure 1). Out of 6,783 compounds, PI3K/Akt/mTOR inhibitors, Src kinase family inhibitors and histone deacetylase inhibitors were predicted as being most effective in reversing this pathologic gene signature. The gene interaction network revealed 15 hub genes as central components with the most interconnections (Table 1). Among these top 15 key gene regulators, IL6, PPARγ and angiotensin receptor type 1 (AGTR1) were the highest ranked druggable targets, based on the drug-gene interaction analysis. Conclusion Our in silico drug repurposing approach identified several potential anti-fibrotic compounds and druggable targets for the treatment of CD-associated intestinal fibrosis. These findings open novel avenues for the development of anti-fibrotic drugs and provide a foundation for future research on cell and pathway-specific mechanisms driving fibrosis in CD.

P0974 Risk factors for anti-TNFα induced paradoxical psoriasis in Inflammatory Bowel Disease and association with an IL-23 receptor polymorphism: A retrospective study

Abstract Background Anti-tumor necrosis factor (TNF)-α therapy is frequently used to treat inflammatory bowel disease (IBD). Paradoxical psoriasis (PP) is a known adverse effect of this drug class resulting in disfiguring skin lesions that may impact quality of life and lead to treatment cessation. To date, there are no tools to identify individuals who are susceptible to developing PP. Variations in the IL-23 receptor (IL23R) gene have been linked to psoriasis onset and may be implicated in PP. The aims of this study are 1. to study the incidence and outcomes of PP in anti-TNFα treated IBD patients at an academic centre in London, Ontario, Canada and 2. to examine risk factors associated with PP including the IL23R variant (IL23R1142G&amp;gt;A). Methods We performed a retrospective study of adult IBD patients treated with anti-TNFα therapies at London Health Sciences Centre between 2012 and 2024. Patient charts were reviewed for clinical variables and disease outcomes from the time of anti-TNFα exposure until treatment discontinuation or last follow-up. Patients’ serum was retrospectively genotyped for the IL23R1142G&amp;gt;A variant. Results We identified 496 IBD patients with 570 unique anti-TNFα exposures between 2012 and 2024. 26 patients developed 29 cases of PP while the remaining 473 patients did not develop PP after exposure to 542 anti-TNFα therapies, corresponding to a PP incidence rate of 5.1% in the study population. There was an increased proportion of patients with PP who had a positive family and personal history of psoriasis, though the latter was not significant (Table 1). The IL23R variant was more common in patients who developed PP compared to those who did not (46.2% vs. 5.1%, OR 16.04, 95% CI 6.69-38.41, Figure 1). The average time to develop PP was 9.5 months, with 55% of patients on high-dose anti-TNFα maintenance regimens. Majority of patients had moderate-to-severe disease (72.4%) based on body surface area (BSA) involvement and required treatment cessation (69.0%). All participants had complete resolution of PP following discontinuation of anti-TNFα therapy. Conclusion We identified an increased frequency of the IL23R1142G&amp;gt;A variant in patients who developed PP following anti-TNFα exposure compared to those who did not. Personal and family history of psoriasis were also more common in those who developed PP. Future studies should investigate other drug and disease characteristics that may predict those at highest risk for this anti-TNFα drug effect.

DOP099 Prolonged Pharmacodynamic Effects of Risankizumab Following Withdrawal in Patients with Moderately to Severely Active Ulcerative Colitis

Abstract Background Risankizumab (RZB) is a high-affinity humanized IgG1 monoclonal antibody that selectively binds to the p19 subunit of human IL-23 cytokine, thereby inhibiting its interaction with the IL-23 receptor.1 RZB was intentionally designed with modifications to the antibody that could contribute to prolonged half-life, low immunogenicity, and increased stability and bioavailability.1 The objective of this post-hoc analysis was to characterise the pharmacokinetic (PK) and pharmacodynamic (PD) effects of RZB following withdrawal in patients with moderately to severely active ulcerative colitis (UC). Methods In the UC maintenance trial (COMMAND, NCT03398135), 272 patients who responded to 12 weeks of intravenous (IV) RZB 1200 mg induction therapy were re-randomised to receive subcutaneous (SC) RZB maintenance dosing (180 mg or 360 mg) or placebo (PBO; RZB withdrawal).2 This analysis evaluated clinical endpoints, PK, and biomarkers of the SC PBO/withdrawal. Change from baseline in partial modified Mayo score, serum RZB concentrations and levels of high-sensitivity C-reactive protein (hs-CRP) and fecal calprotectin (FCP) were assessed at each predetermined study visits throughout the maintenance trial. Results A total of 90 patients were re-randomised to receive PBO (withdrew from RZB induction) in COMMAND. Predicted PK profiles of exposure over time in the PBO/withdrawal group showed that, following the third and final RZB induction dose, residual RZB concentrations lasted for at least 16 weeks before complete washout.3 The PBO/withdrawal group did not have meaningful increases from baseline in partial modified Mayo score until after about week 24 of maintenance (36 weeks since the last dose of RZB) (Figure). Levels of hs-CRP and FCP in the PBO/withdrawal patients remained low throughout maintenance and did not meaningfully increase until week 52. Conclusion Patients with moderately to severely active UC who received IV RZB 1200 mg induction therapy and were re-randomised to PBO exhibited continued response to RZB as demonstrated by disease activity and biomarkers for at least 6 months, exceeding the time of PK washout. hs-CRP and FCP did not increase until week 52 of maintenance and remained below baseline values. This durability of response may have important clinical implications and warrants continued investigation.

P0150 A precision medicine approach for carriers of defined IL2RA polymorphism: JAK inhibition blocks exaggerated IL-2 signalling in vitro, with no difference in in vivo clinical response rates in a small clinical cohort

Abstract Background The rs61839660 (660) polymorphism lies within the IL2RA intronic enhancer and is a causal variant in Crohn’s disease, with a heterozygote frequency of 16.8%. IL-2Ra (CD25) is the high-affinity receptor for IL-2, with binding activating JAK-STAT signalling. We have demonstrated that risk (T) allele carriers exhibit higher CD4+ T cell and natural killer (NK) cell CD25 expression. In response to IL-2, ‘T’ allele carriers show enhanced JAK-STAT signalling, greater CD4+ effector T cell (Teff) pro-inflammatory cytokine release, and enhanced NK cytotoxicity compared to wild-type (CC) subjects.1 We hypothesised that this drives inflammation, and that ‘T’ allele carriers would be more likely to respond to Janus kinase inhibition (JAKi). Tofacitinib (TF) is a JAKi licensed for the treatment of UC. We examined the ability of JAKi to block IL-2-induced JAK-STAT signalling in 660 risk allele carriers in vitro, and explored clinical response to TF in a genotyped UC cohort, with the aim of understanding whether JAKi presents a personalised therapeutic approach in this population. Methods CD patients of each genotype were recruited in collaboration with the NIHR IBD Bioresource.2 We extracted PBMCs and flow-sorted CD4+ Teff and CD56dim NK cells. Cells were cultured for 18h in the presence/absence of 20nM TF, stimulated with IL-2, fixed, and stained for intracellular pSTAT5. TF-treated patients were identified, and provided a blood or saliva sample. Genotyping was performed by qPCR. Data were obtained from patient records, with clinical response defined as a reduction in the Simple Clinical Colitis Activity Index or Partial Mayo Score of &amp;gt;/= 3. Results pSTAT5 levels were elevated in TT subjects’ Teff compared to CC/CT subjects in response to 10IU/ml IL-2 (Fig 1a), with a reduction in Teff pSTAT5 MFI in the presence of TF. In NK cells, pSTAT5 MFI was increased in TT compared to CC donors in response to 100IU/ml IL-2 (Fig 1g). The pSTAT5 response to IL-2 was non-significantly reduced in the presence of TF in both CC and TT subjects’ NK cells. In the real-world UC cohort, there was no significant difference in clinical response to TF between genotypes (Fig 2a), nor in the proportion of patients who had a disease flare on dose reduction or requiring colectomy. There was no difference in TF treatment persistence between genotypes (Fig 2b). Conclusion TF diminishes the in vitro pSTAT5 response to IL-2 in CD4+ Teff and NK cells in carriers of the 660 risk allele. In a UC population, there was no difference in clinical response to TF between genotype cohorts. Our data are limited by the small study population, with larger studies needed to confirm whether the use of JAKi may represent a personalised therapeutic approach in 660 risk allele carriers.

P0171 IL-36 signaling as a drug target in Crohn’s disease patients with IL36RN mutations

Abstract Background The IL-36 signaling pathway has recently been identified as a key regulator of intestinal homeostasis and inflammation. However, the role of mutations in the IL-36R signaling pathway in the pathogenesis of inflammatory bowel disease remains unclear. Methods Mutations in the IL-36 receptor antagonist (IL-36RA, IL36RN) were identified in a cohort of 86 ulcerative colitis patients, 244 Crohn’s disease patients and 45 non-inflamed controls by whole exome sequencing followed by targeted Sanger sequencing. In-depth immune cell profiling of one IL36RN-mutated patient was performed using mass cytometry and multiplexed immunoassays. Overexpression experiments and functional assays characterized identified IL36RN mutations. Clinical and molecular responses of one IL36RN-mutated patient to a combined treatment with the IL-36R-blocking antibody spesolimab and the TNF-blocker certolizumab-pegol were assessed by fecal calprotectin, endoscopy, multiplexed immunoassays and mass cytometry. Results We identified four Crohn’s disease patients with heterozygous missense mutations in IL36RN. Experimental overexpression and functional assays demonstrated that two identified mutations resulted in a reduced protein expression of IL-36RA. In-depth immune profiling of one IL36RN-mutated patient revealed an increased response of PBMCs to IL-36 stimulation and elevated serum levels of IL-36-regulated cytokines. Administration of the IL-36R-blocking antibody spesolimab in combination with certolizumab-pegol over a period of 22 weeks to this patient resulted in a reduction of intestinal inflammation and alterations in immune cell composition and function. Conclusion Our findings indicate that pathogenic IL36RN mutations may contribute to the pathogenesis of Crohn’s disease in a subset of patients and that inhibiting IL-36 signaling in combination with TNF-blockade could offer a personalized therapeutic approach for these patients. Disclaimer Spesolimab was made available based on an out-of-scope request. Boehringer Ingelheim was given the opportunity to review this abstract as a courtesy. Boehringer Ingelheim had no role in the design, analysis or interpretation of the results in this study.

DOP072 The IL1-dependent transcription factor MEOX1 as a driver of differentiation programs in ACKR1+ endothelial cells of inflammatory bowel disease granulation tissue

Abstract Background Activated endothelial cells (ECs) are expanded in IBD tissue and express ACKR11, a chemokine receptor known to mark venular endothelium and enable immune cell trafficking. ACKR1+ ECs have been reported in diseases associated with inflammation and/or fibrosis2, although their role in stromal differentiation is unclear. We investigated the relationship between IL1 and inflammation in IBD and identified an IL1-dependent transcription factor (TF), MEOX1, known to regulate fibrosis in cardiac ischemia3 that is associated with IBD ulcers and expressed in ACKR1+ ECs. Methods We assessed IL-1 bioactivity and performed matched RNA-seq on a cohort of Crohn’s disease (n=23), ulcerative colitis (n=18) and non-IBD (n=17) patients. We performed scRNA-seq of n=208 very early onset (VEO)IBD and control intestinal patient samples. RNA-scope was performed in IBD tissue with/without ulcers. Primary colonic ECs and human umbilical vein (HUV)ECs were stimulated with IL1B +/- TGFB +/- JQ1 (a BRD4 inhibitor that knocked down IL1/MEOX1 driven cardiac fibrosis) followed by qPCR, bulk/scRNA-seq. Results In the paired IL1 proteomic and RNA-seq analyses of IBD tissue, we identified an IL1 and ulcer-specific gene signature which included the TF MEOX1. In scRNA seq analysis, MEOX1 was expressed exclusively in ECs (most robustly in ACKR1+ ECs, which co-expressed the IL1 receptor IL1R1) (Fig 1A). ACKR1+MEOX1+IL1R1+ ECs were significantly expanded in inflamed VEOIBD, especially in those with deep ulcers and IL10R deficiency, and exhibited hallmarks of cell cycle arrest, e.g. expression of CDKN1A (Fig 1B and data not shown). RNA-scope revealed abundant ACKR1+MEOX1+IL1R1+ EC structures specifically in granulation tissue (Fig 1C). In primary colonic ECs, IL1B stimulation induced CDKN1A, unlike TGFB which induced a proliferation/apoptosis phenotype (Fig 1D). In HUVECs, IL1B induced a spindle-shape/fibroblastic EC morphology and ACKR1/MEOX1 expression (data not shown). scRNA-seq revealed an IL1-induced cluster defined by ACKR1, CDKN1A and chemotactic/collagen-producing gene programs, eliminated upon addition of JQ1 (Fig 1E; data not shown). Conclusion ACKR1+ ECs define IBD granulation tissue and co-express IL1R1 as well as the TF MEOX1, which may prove to be a driver of differentiation programs downstream of IL1 signaling at the EC niche that may lead to fibrosis. In silico and in vitro data suggest IL1-driven EC programs are characterized by cell cycle arrest signatures. We hypothesize that the IL1/MEOX1 pathway in ACKR1+ ECs may represent a novel molecular mechanism related to ulcer biology and wound repair in IBD with potential therapeutic implications.

IL-1R1 and IL-18 Signals Regulate Mesenchymal Stromal Cells in an Aged Murine Model of Myelodysplastic Syndromes.

Myelodysplastic syndromes (MDS) are age-related diseases characterized by bone marrow (BM) dysfunction and an increased risk of developing acute leukemia. While there is growing evidence highlighting the crucial role of the BM microenvironment (BMME) in MDS, the specific influence of inflammation on BMME changes, as well as the potential benefits of targeting cytokines therapeutically, remain to be elucidated. We previously found interleukin-1 (IL-1) to be a driver of aging phenotypes of BMME and hematopoietic stem and progenitor cells (HSPCs). In the current study, BM samples from patients with MDS demonstrated upregulated levels of IL-1 family cytokines including IL-18. Utilizing highly purified primary BM-derived mesenchymal stromal cells (MSCs), both interleukin-1b (IL-1b) and IL-18 were found to exert direct effects on MSCs, thus influencing their ability to support HSPCs as well as erythroid progenitors. This confirms the significant involvement of both these IL-1 family cytokines in regulating the BM niche. Furthermore, targeting IL-1 receptor type I (IL-1R1) mitigated these aging phenotypes in elderly mice. We subsequently employed an age-appropriate murine model of MDS by transplanting NUP98-HOXD13 transgenic mice (NHD13Tg) cells into aged wild-type mice. Treatment with inhibitors targeting interleukin-1 receptor-associated kinase 4 (IRAK4) and NLR family pyrin domain containing 3 (NLRP3) reversed the proliferation of dysfunctional MSCs and enhanced their functionality. Additionally, IRAK4 inhibition selectively suppressed MDS clonal cells while sparing non-MDS cells in the BM. These findings suggest that targeting IL-1 signaling holds promise for MDS treatment by addressing the underlying myeloid malignancy and restoring the altered BMME via BM-MSCs.

P0916 Lusvertikimab is efficacious in severe ulcerative colitis (UC) patients with high fecal calprotectin (FCP): results from the CoTikiS study

Abstract Background Fecal calprotectin (FCP) is an objective marker of inflammation in ulcerative colitis (UC) patients and may predict sustained clinical and endoscopic response. In the CoTikiS study (NCT04882007), 2 doses (450 mg or 850 mg) of OSE-127 Lusvertikimab (L) were administered for 10 weeks in patients with moderately or severely active UC. Additional analyses compared the effects of these 2 doses versus placebo on FCP and their efficacy in patients with high FCP at baseline. Methods Stool samples were collected at weeks 0 (w0), 2, 6 and 10 in all patients, frozen at -20°C and shipped to a central laboratory where FCP was measured using a validated analytical method. FCP values were analysed by treatment groups and by visit and the changes versus baseline were compared between each treatment group and placebo. A FCP value &amp;gt; 250 µg/g is considered as a threshold of active inflammatory disease. The efficacy of L850 and L450 was compared to that of placebo in patients with FCP &amp;gt; 250 µg/g at baseline. Results At baseline, FCP was not different between treatment groups: 1192 µg/g, 1088 µg/g, 1148 µg/g and 1459 µg/g for L850, L450, L850/450 and placebo (p=NS) respectively. At w10, FCP was significantly reduced in patients treated with L850 (p=0.018) and L450 (p=0.009). FCP was analysed in patients with baseline values &amp;gt; 250 µg/g, which represented 69.5% of the total population. There were no differences in demographics or disease characteristics between those subgroups. The corresponding baseline FCP values were 1713.1, 1673.9, and 1817.9 µg/g for L850, L450 and placebo, respectively). L450 and L850 significantly decreased FCP as compared to placebo. FCP values were reduced below 250 µg/g at w10 in 45.2% and 38.1% of patients treated with L850 and L450 vs only 18.2% in the placebo group. In this subgroup of patients, the MMS was significantly improved versus placebo at w10: L850mg=-0.94, L450mg=-1.47 and L850/450=-1.16. UC Endoscopic Index of Severity (UCEIS) also markedly improved: L850mg=-0.74, L450 mg=-1.69, L850/450=-1.12 vs placebo. Conclusion Lusvertikimab, a pure IL-7 receptor antagonist, significantly decreased FCP after 10 weeks of treatment and achieved improvements in clinical and endoscopic outcomes in UC patients with active inflammation per FCP &amp;gt; 250 µg/g at baseline. These data strengthen the overall results of the primary and key secondary endpoints from the CoTikiS study.

OP36 Lusvertikimab, a first-in-class IL7 receptor antagonist, in moderate to severe Ulcerative Colitis: results of a multicenter, randomized, placebo-controlled phase II study

Abstract Background OSE127 lusvertikimab (L) is a first-in-class antagonist of IL-7R alpha chain developed for the treatment of ulcerative colitis (UC). The study objectives were to evaluate the efficacy and safety of L in patients (pts) with ulcerative colitis (UC) in a multicentre, randomised, double-blind, placebo-controlled phase 2 study CoTikiS (NCT04882007). Methods Adults with moderately to severely active UC (modified Mayo score [MMS] 4-9) and inadequate response to conventional and/or failure to advanced therapies were randomised 1:1:1 in 3 treatment groups (placebo, L450 mg or L850 mg) administered intravenously at week 0 (W0), W2 and W6. L450mg was dropped at a prespecified futility analysis after 58 patients. It was later showed not futile. The primary endpoint (PE) was the comparison between groups in changes of the MMS from baseline at W10. Key secondary endpoints were clinical remission, endoscopic improvement, endoscopic remission and changes in endoscopic activity by the UC Endoscopic Index of Severity (UCEIS). Adverse events (AEs) and laboratory abnormalities were assessed for safety. Results There were no differences in demographic and disease characteristics between treatment groups (placebo n=49, L450 mg n=35 or L850 mg n=51). The PE was achieved: L450, L850 and pooled dose L450/L850 significantly reduced MMS at W10 as compared to placebo. Key secondary endpoints were also improved by L450, L850 and pooled L450/L850 as compared to placebo. Significantly greater percentages of patients were in clinical remission (22%, 13.0% and 16.2% respectively vs 4.4% for placebo), had an endoscopic remission (34.7%, 19.4%, and 25% vs 12.6 % for placebo) and endoscopic improvement (44.6%, 24.3%, and 31.9% vs 12.6% for placebo) with L450. The UCEIS score was significantly improved with L450. L450 and L850 were well tolerated. The most frequent adverse events for L450, L850 and placebo were lymphopenia (5.6%, 3.9% and 2% respectively), anaemia (2.8%, 0% and 4.1%), pyrexia (5.6%, 0%, 2%), UC exacerbation (2.8%, 3.9%, 6.1%) and Covid 19 (2.8%, 0%, 4.1%). Lymphopenia was of mild severity, transient and did not result in drug interruption, drug withdrawal or increased infection rate. No clinical or biological specific safety signal was reported. Conclusion Lusvertikimab, a pure IL-7 receptor antagonist, demonstrated its clinical and endoscopic efficacy in moderate to severe UC compared to placebo at week 10 with no clinically relevant safety signal. These positive findings support the further clinical development for treatment of UC to elaborate its potential place in the therapeutic armentarium of UC.

Targeting Interleukin-6 Signaling with Tocilizumab in Atherosclerosis: A Meta-Analysis of Anti-Inflammatory Effects and Plaque Stabilization

Atherosclerosis, a chronic inflammatory disease, is the leading cause of cardiovascular disease. Interleukin-6 (IL-6) plays a crucial role in atherogenesis, making it a potential therapeutic target. Tocilizumab, an IL-6 receptor antagonist, has shown promise in reducing inflammation and stabilizing atherosclerotic plaques. This meta-analysis aimed to evaluate the efficacy and safety of tocilizumab in atherosclerosis by analyzing its impact on inflammatory markers and plaque characteristics. A systematic search of PubMed, Embase, and Cochrane Central Register of Controlled Trials was conducted from January 2013 to January 2024. Studies evaluating the effects of tocilizumab on inflammatory markers and plaque characteristics in patients with atherosclerosis were included. Randomized controlled trials (RCTs) and observational studies with a comparative arm were eligible. Data were extracted and pooled using a random-effects model. Nine studies (n=1248 participants) met the inclusion criteria. Tocilizumab significantly reduced CRP levels (standardized mean difference [SMD] -1.23; 95% confidence interval [CI] -1.56 to -0.90; p&lt;0.001) and IL-6 levels (SMD -0.87; 95% CI -1.12 to -0.62; p&lt;0.001) compared to control groups. A significant reduction in plaque volume (SMD -0.45; 95% CI -0.71 to -0.19; p=0.001) and an increase in fibrous cap thickness (SMD 0.38; 95% CI 0.12 to 0.64; p=0.004) were also observed. No significant increase in adverse events was reported in the tocilizumab group. This meta-analysis demonstrates that tocilizumab effectively reduces inflammation and promotes plaque stabilization in atherosclerosis. These findings suggest that tocilizumab may be a promising therapeutic strategy for preventing cardiovascular events in patients with atherosclerosis. Further large-scale RCTs are needed to confirm these findings and establish the long-term safety and efficacy of tocilizumab in this population.

P1190 Generation of blood-derived reference samples with endogenous cytokines

Abstract Background Biomarkers have become an integral part of drug development and decision-making. The quantification of cytokines, commonly used to gain insights into pathological processes in indications such as Inflammatory Bowel Diseases (IBD), and for monitoring therapeutic intervention, should rely on robust and performant methods. Relevant reference samples are crucial for evaluating the performance of biomarker assays implemented in the context of clinical studies, but oHow to evaluate the parallelism of a method for biomarkers that are non-detectable in healthy donors (HD)? oDoes the selectivity of the recombinant protein in the biological matrix reflect the endogenous biomarker? oHow does the stability of the recombinant protein compare with endogenous biomarker? oCan you use incurred samples (informed consent, sufficient volume) for evaluating parallelism and stability? Methods To address these questions, we generated samples with endogenous biomarkers, named MAQC, by spiking supernatants of stimulated PBMC in the serum or plasma from HD. Three to four levels of MAQC per cytokine were prepared and used to assess parallelism, selectivity and long-term stability (LTS) at -80°C of pro- and anti-inflammatory cytokines and chemokines by use of V-plex, S-plex kits from MSD and ELLA kits. For all these parameters, accuracy was determined, with a target acceptance of 70-130% of the nominal value for selectivity and LTS or upstream dilution for parallelism. Results We were able to generate serum and plasma reference samples with low- to high-range levels of Th1 (IFN-g, IL-12p70, IL-2, TNF-α, CCL-2), Th2 (IL-4, IL-13, IL-10), Th17 (IL-17A) and Proinflammatory (IL-6, IL-8, IL-1β) cytokines. Selectivity was acceptable for most cytokines, except for IL-13, IL-4, IL-17A and IL-6. For IL-6, a major interference was observed in some samples, likely due to the presence of soluble IL-6 receptor in the original serum sample. For the other 3 cytokines, interference, leading to a bias close to -30%, was observed that could not be lifted by diluting samples. For all cytokines but IL-13, endogenous diluted similarly as recombinant protein from calibrator. Twelve months LTS was demonstrated for all cytokines in MAQC and comparable to recombinant proteins spiked in human serum. Conclusion To conclude, reference samples with endogenous cytokines/chemokines can be produced from primary immune cells. These can be used to assess parallelism and long-term stability when sufficient volume of matrices with high enough concentrations are not available. These would be even more valuable if they could be commercially available for use as quality controls in validation and clinical studies.

Autoinflammatory diseases. Part 2. Pyrin inflammasomopathies and other enhanced interleukin 1 signaling syndromes

Systemic autoinflammatory diseases (SAIDs) are considered dysregulation disorders of the innate immune system characterized by systemic sterile inflammation independent of infection and autoreactive antibodies or antigen-specific T cells. Autoinflammation is often mediated by inflammasomes; accordingly, inflammasomopathies and other enhanced interleukin (IL) 1 signaling syndromes represent a major classification group of SAIDs. Inflammasomes differ by the type of intracellular receptor which acts as a scaffold protein for the entire complex. Specifically, pyrin is one of the main intracellular sensor proteins that can initiate the formation of inflammasomes. This scientific review is the second in a series of publications jointly aiming to increase medical professionals’ awareness of SAIDs in children. It focuses on the current scientific understanding of pyrin inflammasomopathies which represent a significant cluster of all inflammasomopathies and other enhanced IL-1 signaling syndromes. We performed a focused search over the Web of Science, Scopus, PubMed Central®, Google Scholar databases over the past 10 years using the keywords “autoinflammatory diseases”, “autoinflammation”, “inflammasomopathies”, “pyrin”. The work presents an overview of inflammasomopathies, discusses the immunobiological features of the sensor protein pyrin and pyrin inflammasomes including cellular expression and molecular mechanisms of their activation and signal limitation. The review also presents the clinical and pathogenetic characteristics of the genetically determined pyrin inflammasomopathies and other enhanced IL-1 signaling syndromes: familial Mediterranean fever; pyrin-associated autoinflammation with neutrophilic dermatosis; mevalonate kinase deficiency; PSTPIP1-associated inflammatory diseases; periodic fever, immunodeficiency and thrombocytopenia syndrome; neonatal-onset cytopenia with dyshematopoiesis, autoinflammation, rash, and hemophagocytic lymphohistiocytosis; deficiency of IL-1 receptor antagonist; deficiency of IL-36 receptor antagonist; loss of IL-1 receptor to IL-1 receptor antagonist syndrome.