Iloprost inhibits acute allergic nasal inflammation by GATA3 -ILC2 pathway in mice.

BACKGROUND: Acute allergic nasal inflammation is very common in the clinical allergic diseases, Prostaglandin I2 (PGI2) has been found to effective in combating inflammation. Iloprost, as an analog of PGI2, whose role and mechanisms in the acute allergic nasal inflammation remains unclear. It's necessary to elucidate the efficacy and potential mechanism of Iloprost in acute allergic nasal inflammation. METHODS: 36 female mice were randomly divided into DMSO group, IL 33 group, Iloprost group and IL 33+Iloprost intervention group. Mice were stimulated with IL 33 to construct an acute allergic nasal inflammation model. Hematoxylin and eosin (HE) and periodic acid Schiff reagent (PAS) staining, flow cytometry, Real time PCR and Enzyme linked immunosorbent assay (ELISA) was used to identify the role of Iloprost in acute allergic nasal inflammation. The comparison between multiplied groups was analyzed by ANOVA, and the Bonferroni method was used for further comparison of two groups. RESULTS: Compared with IL 33 group, the inflammatory cell infiltration around the trachea and blood vessels of the lung tissue in the IL 33+ Iloprost group were reduced; goblet cell hyperplasia was observed in airway mucosa of IL 33 group, and the mucus secretion increased; the percentage of EOS and ILC2s in the BALF and lung single cell suspensions in IL 33+ Iloprost group were statistically lower than that of IL 33 group (p < 0.05); The mRNA expression levels of IL 5, IL 13, ST2 and GATA3 in the lung tissue of IL 33 group were higher than those in DMSO group (p < 0.05). After intervention with Iloprost, the mRNA expression levels of IL 5, IL 13, GATA3 and ST2 were lower than those in IL 33 group (p < 0.05) CONCLUSION: Iloprost may potentially inhibit the proliferation and activation of innate lymphoid cells 2 in mice with acute allergic inflammation, which maybe an effective option for the treatment of acute allergic inflammation related diseases.

Methotrexate use, not interleukin 33, is associated with lower carotid intima-media thickness in patients with rheumatoid arthritis

Abstract Background: Rheumatoid arthritis is a risk factor for early mortality due to cardiovascular disease. Interleukin-33 appears to protect against the development of atherosclerosis. The purpose of this study was to investigate the relationship between serum levels of interleukin-33 and its soluble receptor with the presence of subclinical carotid atherosclerosis in rheumatoid arthritis patients. Methods: Rheumatoid arthritis patients without atherosclerotic disease were subjected to clinical and laboratory assessments, including carotid ultrasound. Interleukin-33 and its soluble receptor serum levels were measured by ELISA. Results: 102 patients were included. The prevalence of carotid plaques was 23.5% and the median intima-media thickness was 0.7 mm. The median interleukin-33 and its soluble receptor concentration was 69.1 and 469.8 pg/ml. No association was found between serum interleukin-33 or its soluble receptor and intima-media thickness or plaque occurrence. Each 0.1 mm increase of intima-media thickness raised the odds of plaque occurrence by 5.3-fold, and each additional year of rheumatoid arthritis duration increased the odds of plaque occurrence by 6%. Each additional year in patients age and each one-point increase in the Framingham Risk Score were associated with a 0.004 mm and 0.012 mm increase in intima-media thickness. Methotrexate use was associated with a 0.07 mm reduction in intima-media thickness. Conclusions: Interleukin-33 and its soluble receptor were not associated with subclinical atherosclerosis. Traditional risk factors for atherosclerosis and rheumatoid arthritis duration were associated with intima-media thickness and plaque occurrence; methotrexate use was associated with a lower intima-media thickness.

From proteomics to discovery of first-in-class ST2 inhibitors active in vivo.

Soluble cytokine receptors function as decoy receptors to attenuate cytokine-mediated signaling and modulate downstream cellular responses. Dysregulated overproduction of soluble receptors can be pathological, such as soluble ST2 (sST2), a prognostic biomarker in cardiovascular diseases, ulcerative colitis, and graft-versus-host disease (GVHD). Although intervention using an ST2 antibody improves survival in murine GVHD models, sST2 is a challenging target for drug development because it binds to IL-33 via an extensive interaction interface. Here, we report the discovery of small-molecule ST2 inhibitors through a combination of high-throughput screening and computational analysis. After in vitro and in vivo toxicity assessment, 3 compounds were selected for evaluation in 2 experimental GVHD models. We show that the most effective compound, iST2-1, reduces plasma sST2 levels, alleviates disease symptoms, improves survival, and maintains graft-versus-leukemia activity. Our data suggest that iST2-1 warrants further optimization to develop treatment for inflammatory diseases mediated by sST2.

The therapeutic effect of anti-CD52 treatment in murine experimental autoimmune encephalomyelitis is associated with altered IL-33 and ST2 expression levels.

Experimental autoimmune encephalomyelitis (EAE) mice were administered with murine anti-CD52 antibody to investigate its therapeutic effect and whether the treatment modulates IL-33 and ST2 expression. EAE severity and central nervous system (CNS) inflammation were reduced following the treatment, which was accompanied by peripheral T and B lymphocyte depletion and reduced production of various cytokines including IL-33, while sST2 was increased. In spinal cords of EAE mice, while the number of IL-33+ cells remained unchanged, the extracellular level of IL-33 protein was significantly reduced in anti-CD52 antibody treated mice compared with controls. Furthermore the number of ST2+ cells in the spinal cord of treated EAE mice was downregulated due to decreased inflammation and immune cell infiltration in the CNS. These results suggest that treatment with anti-CD52 antibody differentially alters expression of IL-33 and ST2, both systemically and within the CNS, which may indicate IL-33/ST2 axis is involved in the action of the antibody in inhibiting EAE.