IL-1R1 Protein Research Articles

Small molecule inhibitors of IL-1R1/IL-1β interaction identified via transfer machine learning QSAR modelling

The human interleukin-1 receptor I (IL-1R1) is a cytokine receptor recognized by interleukin 1β (IL-1β), among other cytokines. Over activation of IL-1R1 has been implicated in various inflammatory conditions. This research aims to identify small-molecule inhibitors targeting the hIL1R1/IL1β interaction, employing a multi-task transfer learning approach for quantitative structure-activity relationship (QSAR) modelling. A comprehensive bioactivity dataset from functionally related proteins was utilised to build a robust ensemble machine learning model for predicting IC50 values against the target protein. Despite the availability of antibody-based therapies, the absence of orally available small-molecule inhibitors necessitates their development. By combining model predictions with docking and simulation approaches, the interleukin-1 receptor inhibitor (IRI-1) emerged as a lead compound. It potently inhibited human IL1-R1 with micromolar activity in THP-1 and Saos-2 cells and demonstrated good biocompatibility. Western blot analysis revealed that IRI-1 inhibits IL-1β-mediated phosphorylation of IL1-R1, JNK, IRAK-4, and ERK in THP-1 cells. Furthermore, molecular dynamics simulations confirmed the structural stability of the protein-ligand complexes. This study highlights the effectiveness of multi-task transfer learning approaches for building robust QSAR models against novel proteins or those with limited bioactivity data, such as hIL-1β/IL-1R1 protein.

The interleukin-1 receptor type-1 in disturbed flow-induced endothelial mesenchymal activation.

Atherosclerosis is a progressive disease that develops in areas of disturbed flow (d-flow). Progressive atherosclerosis is characterized by bulky plaques rich in mesenchymal cells and high-grade inflammation that can rupture leading to sudden cardiac death or acute myocardial infarction. In response to d-flow, endothelial cells acquire a mesenchymal phenotype through endothelial-to-mesenchymal transition (EndMT). However, the signaling intermediaries that link d-flow to EndMT are incompletely understood. In this study we found that in human atherosclerosis, cells expressing SNAI1 (Snail 1, EndMT transcription factor) were highly expressed within the endothelial cell (EC) layer and in the pre-necrotic areas in unstable lesions, whereas stable lesions did not show any SNAI1 positive cells, suggesting a role for EndMT in lesion instability. The interleukin-1 (IL-1), which signals through the type-I IL-1 receptor (IL-1R1), has been implicated in plaque instability and linked to EndMT formation in vitro. Interestingly, we observed an association between SNAI1 and IL-1R1 within ECs in the unstable lesions. To establish the causal relationship between EndMT and IL-1R1 expression, we next examined IL-1R1 levels in our Cre-lox endothelial-specific lineage tracing mice. IL-1R1 and Snail1 were highly expressed in ECs under atheroprone compared to athero-protective areas, and oscillatory shear stress (OSS) increased IL-1R1 protein and mRNA levels in vitro. Exposure of ECs to OSS resulted in loss of their EC markers and higher induction of EndMT markers. By contrast, genetic silencing of IL-1R1 significantly reduced the expression of EndMT markers and Snail1 nuclear translocation, suggesting a direct role for IL-1R1 in d-flow-induced EndMT. In vivo, re-analysis of scRNA-seq datasets in carotid artery exposed to d-flow confirmed the IL-1R1 upregulation among EndMT population, and in our partial carotid ligation model of d-flow, endothelial cell specific IL-1R1 KO significantly reduced SNAI1 expression. Global inhibition of IL-1 signaling in atherosclerosis as a therapeutic target has recently been tested in the completed CANTOS trial, with promising results. However, the data on IL-1R1 signaling in different vascular cell-types are inconsistent. Herein, we show endothelial IL-1R1 as a novel mechanosensitive receptor that couples d-flow to IL-1 signaling in EndMT.

Intratumoral IL-1R1 expression delineates a distinctive molecular subset with therapeutic resistance in patients with gastric cancer

BackgroundWith the essential role of interleukin-1 signaling in cancer-related inflammation, IL-1R1, the main receptor for both IL-1α and IL-1β, demonstrated therapeutic potential in several types of cancer, which has been...

Short hairpin RNA interference targeting interleukin 1 receptor type I in the paraventricular nucleus attenuates hypertension in rats.

Blood pressure is controlled by tonic sympathetic activities, excessive activation of which contributes to the pathogenesis and progression of hypertension. Interleukin (IL)-1β in the paraventricular nucleus (PVN) is involved in sympathetic overdrive and hypertension. Here, we investigated the therapeutic effects of IL-1 receptor type I (IL-1R1) gene silencing in the PVN on hypertension. Recombinant lentivirus vectors expressing a short hairpin RNA (shRNA) targeting IL-1R1 (Lv-shR-IL-1R1) or a control shRNA were microinjected into PVN of spontaneously hypertensive rats (SHRs) and normotensive WKY rats. The fluorescence of green fluorescent protein-labelled vectors appeared at 2weeks after injection and persisted for at least 8weeks. IL-1R1 protein expression in the PVN was reduced 4weeks after Lv-shR-IL-1R1 injection in SHRs. IL-1R1 interference also reduced basal sympathetic activity, cardiac sympathetic afferent reflex in SHRs. Depressor effects were observed from week 2 to 10 after Lv-shR-IL-1R1 treatment in SHRs, with the most prominent effects seen at the end of week 4. Furthermore, Lv-shR-IL-1R1 treatment decreased the ratio of left ventricular weight to body weight and cross-sectional areas of myocardial cells in SHRs. Additionally, Lv-shR-IL-1R1 treatment prevented an increase in superoxide anion and pro-inflammatory cytokines (PICs, TNF-α and IL-1β) in the PVN of SHR, and upregulated anti-inflammatory cytokine (AIC, IL-10) expression. These results indicate that shRNA interference targeting IL-1R1 in the PVN decreases arterial blood pressure, attenuates excessive sympathetic activity and cardiac sympathetic afferent reflex, and improves myocardial remodelling in SHRs by restoring the balance between PICs and AICs to attenuate oxidative stress.

Interleukin-1 receptor type 1 is overexpressed in neurons but not in glial cells within the rat superficial spinal dorsal horn in complete Freund adjuvant-induced inflammatory pain

BackgroundAll known biological functions of the pro-inflammatory cytokine interleukin-1β (IL-1β) are mediated by type 1 interleukin receptor (IL-1R1). IL-1β–IL-1R1 signaling modulates various neuronal functions including spinal pain processing. Although the role of IL-1β in pain processing is generally accepted, there is a discussion in the literature whether IL-1β exerts its effect on spinal pain processing by activating neuronal or glial IL-1R1. To contribute to this debate, here we investigated the expression and cellular distribution of IL-1R1 in the superficial spinal dorsal horn in control animals and also in inflammatory pain.MethodsExperiments were performed on rats and wild type as well as IL-1R1-deficient mice. Inflammatory pain was evoked by unilateral intraplantar injection of complete Freund adjuvant (CFA). The nociceptive responsiveness of control and CFA-treated animals were tested daily for withdrawal responses to mechanical and thermal stimuli before and after CFA injection. Changes in the expression of 48 selected genes/mRNAs and in the quantity of IL-1R1 protein during the first 3 days after CFA injection were measured with the TaqMan low-density array method and Western blot analysis, respectively. The cellular localization of IL-1R1 protein was investigated with single and double staining immunocytochemical methods.ResultsWe found a six times and two times increase in IL-1R1 mRNA and protein levels, respectively, in the dorsal horn of CFA-injected animals 3 days after CFA injection, at the time of the summit of mechanical and thermal allodynia. Studying the cellular distribution of IL-1R1, we found an abundant expression of IL-1R1 on the somatodendritic compartment of neurons and an enrichment of the receptor in the postsynaptic membranes of some excitatory synapses. In contrast to the robust neuronal localization, we observed only a moderate expression of IL-1R1 on astrocytes and a negligible one on microglial cells. CFA injection into the hind paw caused a remarkable increase in the expression of IL-1R1 in neurons, but did not alter the glial expression of the receptor.ConclusionThe results suggest that IL-1β exerts its effect on spinal pain processing primarily through neuronal IL-1R1, but it can also interact in some extent with IL-1R1 expressed by astrocytes.

Expression and localization of interleukin 1 beta and interleukin 1 receptor (type I) in the bovine endometrium and embryo

The interleukin-1 (IL1) system likely mediates mammalian embryo–maternal communication. In cattle, we have reported that the uterine fluid of heifers carrying early embryos shows downregulated IL1 beta (IL1B), which could lead to reduced NFkB expression and dampening of maternal innate immune responses. In this work, we assessed the expression of IL 1 beta (IL1B) and its receptor, interleukin 1 receptor type I (IL1R1) in the bovine endometrium and embryos by RT-PCR, immunohistochemistry and Western blot at the time of blastocyst development. Day 8 endometrium, both collected from animals after transfer of day 5 embryos (ET) and sham transferred (ST), showed IL1B and IL1R1 mRNA transcription and protein co-localization. Similarly, day 8 blastocyst, from ET animals and entirely produced in vitro, showed IL1R1 mRNA transcription and IL1B and IL1R1 protein co-localization. IL1B mRNA was detected in the analyzed blastocysts, but at very low levels that precluded its quantification. IL1B and IL1R1 immunostaining was observed in luminal epithelial cells, glandular epithelium and stromal cells. The presence of embryos increased endometrial IL1B protein locally, while no differences regarding IL1R1 protein and IL1B and IL1R1 mRNA were detected. These results suggest that the early preimplantation bovine embryo in the maternal tract might interact with the maternal immune system through the IL1 system. Such a mechanism may allow the embryo to elicit local endometrial responses at early stages, which are required for the development of a receptive endometrium.

Interleukin 1 type 1 receptor restore: a genetic mouse model for studying interleukin 1 receptor-mediated effects in specific cell types.

Interleukin-1 (IL-1) mediates diverse neurophysiological and neuropathological effects in the CNS through type I IL-1 receptor (IL-1R1). However, identification of IL-1R1-expressing cell types and cell-type-specific functions of IL-1R1 remains challenging. In this study, we created a novel genetic mouse model in which IL-1R1 gene expression is disrupted by an intronic insertion of a loxP flanked disruptive sequence that can be deleted by Cre recombinase, resulting in restored IL-1R1 gene expression under its endogenous promoters. A second mutation was introduced at stop codon of the IL-1R1 gene to allow tracking of the restored IL-1R1 protein by a 3HA tag and IL-1R1 mRNA by tdTomato fluorescence. These animals were designated as IL-1R1(r/r) and exhibited an IL-1R1 knock-out phenotype. We used IL-1R1 globally restored mice (IL-1R1(GR/GR)) as an IL-1R1 reporter and observed concordant labeling of IL-1R1 mRNA and protein in brain endothelial cells. Two cell-type-specific IL-1R1 restore lines were generated: Tie2Cre-IL-1R1(r/r) and LysMCre-IL-1R1(r/r). Brain endothelial COX-2 expression, CNS leukocyte infiltration, and global microglia activation induced by intracerebroventricular injection of IL-1β were not observed in IL-1R1(r/r) or LysMCre-IL-1R1(r/r) mice, but were restored in Tie2Cre-IL-1R1(r/r) mice. These results reveal IL-1R1 expression in endothelial cells alone is sufficient to mediate these central IL-1-induced responses. In addition, ex vivo IL-1β stimulation increased IL-1β expression in bone marrow cells in wild-type, Tie2Cre-IL-1R1(r/r), and LysMCre-IL-1R1(r/r), but not IL-1R1(r/r) mice. These results demonstrate this IL-1R1 restore model is a valuable tool for studying cell-type-specific functions of IL-1R1.

Attempt to Explore the Binding Mechanism of IL-1β Inhibitors via Molecular Docking Studies

IL-1β is an important cytokineinvolved in several immune responses. IL-1β exerts its effect by binding with its receptorcalled IL-1R1 and leading to a series of intra-cellular signalling. The over-expression of IL-1β leads to immunological complications including arthritis and auto-immune disorders. Currently there are several drugs in the market to cure the inflammation either by inhibiting the production of IL-1β or affecting its signal cascade. The hindrance in the interaction between IL-1β interaction and its receptor can stop its function hence hope to cure inflammatory diseases. This study presents a docking analysis of five commercially available drugs at the IL-1β/IL-1R1 protein interface. This study would give an insight for designing the drugs, capable to block the direct interaction of IL-1β with its receptor ultimately leading to some more consistent cure for inflammatory diseases.

Human chorionic gonadotropin exhibits a direct downregulatory effect on the expression of the inhibitory type II interleukin 1 receptor in human endometrial cells

Human chorionic gonadotropin exhibits a direct downregulatory effect on the expression of the inhibitory type II interleukin 1 receptor in human endometrial cells