High IL-33 Expression Research Articles

Interleukin-33 in cutaneous wound healing

Barrier tissues like the skin, gastrointestinal tract, and respiratory system exhibit high IL-33 expression. IL-33 expression increases in humans and mice during cutaneous wound healing. Following skin injury, IL-33 alerts immune cells via its receptor ST2, modulating the inflammatory response and acting as a nuclear transcription factor to regulate target cell function. Multiple studies have verified the vital function of IL-33 in cutaneous wound healing; however, the mechanisms remain contentious. This review provides an overview of the progress made in comprehending the biological characteristics of IL-33, including its production, its regulatory effects on target cells’ activities, and its impact on chronic wounds. This overview aids in elucidating the mechanisms through which IL-33 contributes to wound healing, thereby offering insights into potential therapeutic strategies for treating chronic wounds.

Dexamethasone Suppresses IL-33-exacerbated Malignant Phenotype of U87MG Glioblastoma Cells via NF-κB and MAPK Signaling Pathways.

Interleukin (IL)-33 is highly expressed in glioblastoma (GBM) and promotes tumor progression. Targeting IL-33 may be an effective strategy for the treatment of GBM. Dexamethasone (DEX) is a controversial drug routinely used clinically in GBM therapy. Whether DEX has an effect on IL-33 is unknown. This study aimed to investigate the effect of DEX on IL-33 and the molecular mechanisms involved. U87MG cells were induced by tumor necrosis factor (TNF)-α to express IL-33 and then treated with DEX. The mRNA levels of IL-33, NF-κB p65, ERK1/2, and p38 were determined by real-time quantitative PCR. The expression of IL-33, IkBα (a specific inhibitor of NF-κB) and MKP-1 (a negative regulator of MAPK), as well as the phosphorylation of NF-κB, ERK1/2 and p38 MAPK, were detected by Western blotting. The secretion of IL-33 was measured by ELISA. The proliferation, migration and invasion of U87MG cells were detected by CCK8 and transwell assays, respectively. DEX significantly reduced TNF-α-induced production of IL-33 in U87MG cells, which was dependent on inhibiting the activation of the NF-κB, ERK1/2 and p38 MAPK signaling pathways, and was accompanied by the increased expression of IkBα but not MKP-1. Furthermore, the proliferation, migration and invasion of U87MG cells exacerbated by IL-33 were suppressed by DEX. DEX inhibited the production and tumor-promoting function of IL-33. Whether DEX can benefit GBM patients remains controversial. Our results suggest that GBM patients with high IL-33 expression may benefit from DEX treatment and deserve further investigation.

The association of serum IL-33/ST2 expression with hepatocellular carcinoma

BackgroundIL-33 is a multifunctional cytokine with dual functions. However, the clinicopathological and prognostic significance of IL-33 in cancer patients, especially in patients with hepatocellular carcinoma (HCC), remains controversial. Therefore, we conducted a study of 565 patients with HCC and 561 healthy controls and performed a meta-analysis to quantitatively evaluate the above problems.MethodsWe collected blood from 565 patients with HCC and 561 healthy controls. ELISA was used to detect the concentrations of IL-33 and ST2 in the serum, and RT‒PCR was used to detect the levels of IL-33 and ST2 mRNA. Meanwhile, we collected comprehensive literature on IL-33 and the clinical characteristics of cancer patients retrieved from the PubMed, Web of Science and CNKI databases as of December 2022. An odds ratio (OR) with a 95% confidence interval (CI) was used to estimate the impact through overall and stratified analyses.ResultsCompared with the healthy control group, the levels of ST2 mRNA and serum in the peripheral blood of HCC patients increased (p < 0.05), while the levels of IL-33 mRNA and serum showed no significant difference between the two groups (p > 0.05). In the meta-analysis section, at the tissue level, the overall analysis showed that the expression of IL-33 was positively correlated with tumor stage, histological grade, distant metastasis, and tumor size. Compared with patients with low IL-33 expression, the 3-year overall survival (OS) rate (OR = 3.467, p < 0.001) and 5-year OS rate (OR = 2.784, p < 0.001) of patients with high IL-33 expression were lower. At the serum expression level, the overall analysis showed that the expression of IL-33 increased the risk of cancer, and the serum level of IL-33 was positively correlated with tumor stage and vascular invasion.ConclusionIL-33/ST2 is a useful predictive or prognostic biomarker in clinical evaluation and may be used as a potential therapeutic target, but much research is needed to verify this hypothesis.

Fungal mycobiome drives IL-33 secretion and type 2 immunity in pancreatic cancer.

TH2 cells and innate lymphoid cells 2 (ILC2) can stimulate tumor growth by secreting pro-tumorigenic cytokines such as interleukin-4 (IL-4), IL-5, and IL-13. However, the mechanisms by which type 2 immune cells traffic to the tumor microenvironment are unknown. Here, we show that oncogenic KrasG12D increases IL-33 expression in pancreatic ductal adenocarcinoma (PDAC) cells, which recruits and activates TH2 and ILC2 cells. Correspondingly, cancer-cell-specific deletion of IL-33 reduces TH2 and ILC2 recruitment and promotes tumor regression. Unexpectedly, IL-33 secretion is dependent on the intratumoral fungal mycobiome. Genetic deletion of IL-33 or anti-fungal treatment decreases TH2 and ILC2 infiltration and increases survival. Consistently, high IL-33 expression is observed in approximately 20% of human PDAC, and expression is mainly restricted to cancer cells. These data expand our knowledge of the mechanisms driving PDAC tumor progression and identify therapeutically targetable pathways involving intratumoral mycobiome-driven secretion of IL-33.

Role of Interleukin-33 in Staphylococcus epidermidis-Induced Septicemia.

Interleukin (IL)-33 is a member of the IL-1 family, which plays an important role in inflammatory response. In this study, we evaluated the effect of IL-33 on septicemia and the underlying mechanisms by establishing a Staphylococcus epidermidis (S. epidermidis)-induced septicemic mouse model. The expression of IL-33, IL-1α, IL-1β, IL-6, IL-17A, IL-22, and PGE2 were measured by double antibody sandwich enzyme-linked immunosorbent assay, and bacterial colony formation in peripheral blood and kidneys were counted postinfection. The percentages of neutrophils, eosinophils, and inflammatory monocytes were evaluated by flow cytometry, and tissue damage was assessed by hematoxylin and eosin (H&E) staining. The survival of septicemic mice was monitored daily. IL-33 expression was significantly augmented following S. epidermidis infection. High IL-33 expression significantly decreased the survival of model mice, and aggravated the damage of lung, liver, and kidney tissues. However, administration of ST2 (receptor for IL-33) to the S. epidermidis-infected mice blocked the IL-33 signaling pathway, which elevated PGE2, IL-17A, and IL-22, and promoted healing of organ damage. In addition, ST2 suppressed the mobilization of inflammatory monocytes, but promoted the accumulation of neutrophils and eosinophils in S. epidermidis-infected mice. Inhibition of PGE2, IL-17A, and IL-22 facilitated the development of septicemia and organ damage in S. epidermidis-infected mice, as well as reducing their survival. Our findings reveal that IL-33 aggravates organ damage in septicemic mice by inhibiting PGE2, IL-17A, and IL-22 production.

Functional variant of IL33 is associated with survival of osteosarcoma patients

ObjectivesPrevious genome-wide association study showed that GLDC/IL33 loci were associated with overall survival in patients with osteosarcoma (OS). We performed a replication study to explore whether variants of GLDC/IL33 are associated with the survival of OS patients and to further verify their functional role in the gene expression. MethodsA total of 216 patients with OS were enrolled. The overall survival time was calculated from the date of diagnosis till the date of last follow-up or mortality. Two SNPs were genotyped, including rs55933544 and rs74438701. OS specimens were obtained from 72 patients during surgery. The gene expression level of IL33 and GLDC was evaluated by qPCR. Patients were classified into two groups according to the 5-year overall survival (death/survival). The chi-square test was used to analyze difference of genotype frequency. The Student t-test was used to compare the gene expression level between different genotypes. Cumulative survival time was calculated by the Kaplan–Meier method and analyzed by the log-rank test. ResultsGenotype TT of rs55933544 was significantly associated with the event of death (0.176 vs. 0.061, p < 0.001). Patients with no risk allele T of rs55933544 showed a 5-year overall survival of 81.4% (110/141), which was significantly higher than an overall survival of 55.0% (29/54) for patients with one risk allele and 44.8% (12/21) for patients with two risk alleles (p < 0.01). Genotype TT of rs55933544 were indicative of remarkably lower expression of IL33 than genotype CC (0.00041 ± 0.00025 vs. 0.00065 ± 0.00031, p = 0.04). Patients with low IL33 expression presented remarkably worse survival as compared with the patients with high IL33 expression (p < .01) ConclusionsVariant rs55933544 was associated with the survival time of OS patients. IL33 may contribute to a poor prognosis of OS. Further investigation into the biological mechanisms by which IL33 influences the overall survival can shed light on the improvement of clinical outcome for OS patients.

Interleukin-33/ST2-Mediated Inflammation Plays a Critical Role in the Pathogenesis and Severity of Type I Autoimmune Hepatitis.

Interleukin (IL)‐33 was recently described as a new member of the IL‐1 family; members of this family have proinflammatory activity. IL‐33 and its soluble receptor ST2 (sST2) have been implicated in the pathogenesis of autoimmune diseases. This study investigated serum IL‐33 and sST2 in type I autoimmune hepatitis (AIH) and the relationship of these molecules with clinical and pathologic parameters. Subjects included 65 patients with AIH who were diagnosed in our hospital. The control population included 17 healthy individuals and 36 patients with primary biliary cholangitis (PBC). Mean age at AIH diagnosis was 55.5 years, and the male‐to‐female ratio was 6:59. Serum IL‐33 and sST2 levels were significantly higher in patients with AIH than in those with PBC or controls. Importantly, immunohistochemistry revealed high IL‐33 expression in liver sections from patients with AIH. In particular, serum IL‐33 and sST2 levels were significantly higher in acute‐onset AIH than in chronic‐onset AIH. Serum IL‐33 levels were positively correlated with serum total bilirubin (TB), alanine aminotransferase (ALT), and necroinflammatory activity in AIH. We performed multivariate logistic regression analysis and found serum IL‐33 levels to be independent factors for severe activity. Serum sST2 levels were positively correlated with serum TB and ALT and negatively correlated with serum albumin and prothrombin time in AIH. In particular, serum sST2 levels were significantly higher in severe symptoms of AIH. Serum IL‐33 and sST2 levels in patients with AIH responsive to treatment with prednisolone were significantly decreased after treatment. Interestingly, serum IL‐33 level was associated with a significantly increased risk of relapse. Conclusion: IL‐33/ST2 may play an important role in the pathogenesis and severity of AIH and may be a promising target for AIH therapy.

IL-33 Released in the Liver Inhibits Tumor Growth via Promotion of CD4+ and CD8+ T Cell Responses in Hepatocellular Carcinoma.

IL-33 released by epithelial cells and immune cells functions as an alarmin and can induce both type 1 and type 2 immune responses. However, the role of IL-33 release in tumor development is still not clear. In this study, we examined the function of released IL-33 in murine hepatocellular carcinoma (HCC) models by hydrodynamically injecting either IL-33-expressing tumor cells or IL-33-expressing plasmids into the liver of tumor-bearing mice. Tumor growth was greatly inhibited by IL-33 release. This antitumor effect of IL-33 was dependent on suppression of tumorigenicity 2 (ST2) because it was diminished in ST2-/- mice. Moreover, HCC patients with high IL-33 expression have prolonged overall survival compared with the patients with low IL-33 expression. Further study showed that there were increased percentages and numbers of activated and effector CD4+ and CD8+ T cells in both spleen and liver in IL-33-expressing tumor-bearing mice. Moreover, IFN-γ production of the CD4+ and CD8+ T cells was upregulated in both spleen and liver by IL-33. The cytotoxicity of CTLs from IL-33-expressing mice was also enhanced. In vitro rIL-33 treatment could preferentially expand CD8+ T cells and promote CD4+ and CD8+ T cell activation and IFN-γ production. Depletion of CD4+ and CD8+ T cells diminished the antitumor activity of IL-33, suggesting that the antitumor function of released IL-33 was mediated by both CD4+ and CD8+ T cells. Taken together, we demonstrated in murine HCC models that IL-33 release could inhibit tumor development through its interaction with ST2 to promote antitumor CD4+ and CD8+ T cell responses.

Impact of chronic rhinosinusitis on severe asthma patients.

Coexistence of chronic rhinosinusitis (CRS) with asthma appears to impair asthma control. Type-2 innate lymphoid cells (ILC2s) respond to the cytokines of thymic stromal lymphopoietin (TSLP), interleukin (IL)-25 and IL-33, thus contributing to airway diseases such as CRS and asthma. We investigate whether the augmented Th2-cytokines in CRS might be related to sinonasal tract ILC2s corresponding to enhanced IL-25, IL-33 and TSLP release in severe asthmatics, and be involved in asthma control. Twenty-eight asthmatics (12 non-severe and 16 severe) with CRS receiving nasal surgery were enrolled. The predicted FEV1 inversely associated with CRS severity of CT or endoscopy scores. Higher expression of Th2-driven cytokines (IL-4, IL-5, IL-9, and IL-13), TSLP, IL-25 and IL-33 in nasal tissues was observed in severe asthma. Severe asthmatics had higher ILC2 cell counts in their nasal tissues. ILC2 counts were positively correlated with Th2-cytokines. Nasal surgery significantly improved asthma control and lung function decline in severe asthma and CRS. The higher expression of IL-33/ILC2 axis-directed type 2 immune responses in nasal tissue of CRS brought the greater decline of lung function in severe asthma. ILC2-induced the upregulated activity of Th2-related cytokines in asthmatics with CRS may contribute to a recalcitrant status of asthma control.

Expression of interleukin-33 is correlated with poor prognosis of patients with squamous cell carcinoma of the tongue.

The aim of this study was to clarify the role of IL-33 in tumor progression. Surgical specimens from 81 patients with squamous cell carcinoma of the tongue were studied using immunohistochemistry. Primary tumor sections were analyzed for IL-33 and ST2 expression. To examine the influence of IL-33 on the microenvironment of the tumor, we determined the mast cell density (MCD) and microvessel density of the stroma. Patients with high IL-33 expression had a significantly worse prognosis (p=0.004). IL-33 expression was significantly elevated in patients with local and nodal recurrence (p=0.014 and p=0.019). ST2 expression was also associated with a worse prognosis (p=0.024) and was significantly elevated in patients with nodal recurrence (p=0.004). MCD was associated with worse prognosis (p=0.038) and correlated significantly with IL-33 expression (r=0.626, p<0.001). Micovessels in the stroma were significantly increased in the high IL-33 group (p<0.001). These data suggest that the IL-33/ST2 axis contributes to tumor aggressiveness and affects the tumor microenvironment. Immunohistochemical evaluation of IL-33 and ST2 is useful for identifying patients at a high risk for poor prognosis.

House dust mite increases IL-33 and thymic stromal lymphopoietin (TSLP) gene expression in response to human rhinovirus 1B in murine bone marrow-derived macrophages. (HYP6P.276)

Abstract Acute viral infections are the most frequent cause of asthma exacerbations, and are therefore responsible for the majority of healthcare costs attributed to asthma. Human rhinovirus is the most common identified one in children and adults. It has been shown that IL-33- driven mechanism initiates TH2 responses to the clinically relevant allergens house dust mite (HDM). We have shown that TSLP is increased in asthma exacerbation. Alveolar macrophages have higher expression of IL-33 and TSLP in asthma. To determine whether HDM can have an effect on IL-33 and TSLP gene expression in response to human rhinovirus (RV), we treated bone marrow-derived macrophages (BMM) with HDM in the presence of M-CSF and infected them with RV1B. RV1B induced expression of IL-33 (2-fold, P-value&amp;lt;0.001) and TSLP (2-fold P-value&amp;lt;0.05) in HDM- treated macrophages after 24 hours compared to HDM non-treated BMM. RV1B infection caused an increase in IL-33 in IL-33 (P-value&amp;lt;0.01) and TSLP ( P-value&amp;lt;0.01) in HDM treated BMM compared to UV-treated RV1B group. There was no increase in IL-33 and TSLP gene expression in response to RV1B in the HDM-treated BMM at eight hours compared to UV-treated RV1B group, while HDM non-treated BMM showed increase in IL-33 (P-value&amp;lt;0.01) and TSLP (P-value=0.059 ) in response to RV1B compared to UV-treated RV1B. These results suggest that HDM increases IL-33 and TSLP gene expression in macrophages in response to RV1B which can play a role in asthma exacerbations.