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Background CD4 + T cell polarization plays a critical role in the pathogenesis of allergy. How to modulate the skewed CD4 + T cell polarization is less clear. The specific immunotherapy (SIT) is the only specific remedy for the treatment of allergic diseases; the therapeutic effect is to be improved. Objectives This study aims to investigate the role of interleukin (IL)-18 in enhancing the therapeutic effect of SIT. Methods A peanut allergy mouse model was developed and treated with SIT or/and IL-18. CD4 + T cell apoptosis was assessed by flow cytometry. The expression of Fas ligand (FasL) was observed by quantitative real time RT-PCR and Western blotting. Interferon-γ in the culture medium was determined by enzyme-linked immunosorbent assay. The fasL gene promoter methylation in CD4 + T cells was assessed by methylation specific PCR. Results The results showed that lower levels of IL-18 were detected in allergic mice; administration of IL-18 significantly enhanced the therapeutic effect of SIT on suppressing the allergic inflammation in the mouse intestine. In the cell culture studies, IL-18 increased the TCR-dependent CD4 + T cell apoptosis, the expression of FasL in CD4 + T cells, the production of Interferon-γ and the demethylation of the FasL promoter in CD4 + T cells. Conclusions Administration of IL-18 enhances the effect of SIT on suppressing allergic inflammation in the mouse intestine via enhancing the TCR-dependent CD4 + T cell apoptosis.

Background The prevalence of food allergy has increased dramatically during the last three decades, but currently there was no effective therapy except avoidance of allergen. This study aimed to investigate the effect of a modified Chinese herbal formula, Formula-3, on mast cell degranulation and the anti-allergic activity in both animal and cell models. Methods With OVA-sensitized food allergic model in Brown–Norway rats, we checked tissue injury in the small intestines by H&E staining. The Th2 cytokine levels and IgE production in serum or supernatant of the intestinal mucosa homogenates were analyzed by ELISA. Meanwhile, rat peritoneal mast cell activation and degranulation were examined by Toluidine Blue Stain and the release of histamine was measured. Furthermore, the regulation of Formula-3 on Ca 2 + mobilization was investigated by probing intracellular Ca 2 + with fluo-4 fluorescence. The direct effect of Formula-3 on mast cell stabilization was also studied in RBL-2H3 cell line. Results In vivo Formula-3 administration significantly reduced tissue damage in the small intestines of rat and suppressed Th2 cytokine secretion and IgE production. We demonstrated that Formula-3 treatment significantly suppressed FceR1-mediated mast cell degranulation no matter in OVA-challenged allergic rats or IgE-sensitized RBL-2H3 cell line. Furthermore, Formula-3 significantly decreased Ca 2 + influx through store-operated calcium channels (SOCs) evoked by dinitrophenyl-BSA or thapsigargin in mast cells. Conclusion Taken together, our data indicate that Formula-3 stabilizes mast cells by suppressing FceR1-induced Ca 2 + mobilization mainly through inhibiting Ca 2 + entry via SOCs, thus exerting a protective effect against OVA-sensitized food allergy.

The importance of Ca(2+) influx via store-operated calcium channels (SOCs) leading to mast cell degranulation is well known in allergic disease. However, the underlying mechanisms are not fully understood. With food-allergic rat model, the morphology of degranulated mast cell was analysed by toluidine blue stain and electron microscope. Ca(2+) influx via SOCs was checked by Ca(2+) imaging confocal microscope. Furthermore, the mRNA and protein expression of SOCs subunits were investigated using qPCR and Western blot. We found that ovalbumin (OVA) challenge significantly increased the levels of Th2 cytokines and OVA-specific IgE in allergic animals. Parallel to mast cell activation, the levels of histamine in serum and supernatant of rat peritoneal lavage solution were remarkably increased after OVA treatment. Moreover, the Ca(2+) entry through SOCs evoked by thapsigargin was increased in OVA-challenged group. The mRNA and protein expressions of SOC subunits, stromal interaction molecule 1 (STIM1) and Orail (calcium-release-activated calcium channel protein 1), were dramatically elevated under food-allergic condition. Administration of Ebselen, a scavenger of reactive oxygen species (ROS), significantly attenuated OVA sensitization-induced intracellular Ca(2+) rise and upregulation of SOCs subunit expressions. Intriguingly, pretreatment with PI3K-specific inhibitor (Wortmannin) partially abolished the production of ROS and subsequent elevation of SOCs activity and their subunit expressions. Taken together, these results imply that enhancement of SOC-mediated Ca(2+) influx induces mast cell activation, contributing to the pathogenesis of OVA-stimulated food allergy. PI3K-dependent ROS generation involves in modulating the activity of SOCs by increasing the expressions of their subunit.

Food allergy (FA) is an adverse immune response to certain innocent food. It is estimated about 2% to 6% of the general population suffer from FA. Symptoms of a food allergic reaction may involve the gastrointestinal tract or/and other organs. The gut microbiota plays a critical role in diet-induced health problems. Whether the changes in the composition of the intestinal microbiota regulate allergic responses to food remains poorly understood. Thus, we created an FA animal model, sequenced the V4-V5 regions of 16S rRNA genes to characterize the genera abundance of gut microbiota. The results showed that mice under FA condition showed different gut bacterial structures. Diverse distribution of the bacterial species was identified between FA and control groups. FA altered the components of intestinal Microbiota in mice. The dysbiosis of the gut metagenome correlated with the development of the FA.

Background: Rheumatoid arthritis (RA) is a very complicated autoimmune disease with apparent synovial hyperplasia and cartilage and bone destruction. Aims: In the present study, we aimed to determine whether the pathogenesis of RA correlates with food allergy and which allergen(s) are relevant. Materials and Methods: We used type-II collagen (CII) to induce arthritis (collagen-induced arthritis, CIA) model in Wistar rats, and the development of arthritis was evaluated accordingly by scoring system. Proinflammatory cytokine levels in plasma were measured by enzyme-linked immunosorbent assay (ELISA), and concentrations of circulating immune complexes (CICs) were analyzed by C1q solid phase method. Furthermore, food-specific immunoglobulin G (IgG) and immunoglobulin E (IgE) levels were determined in the CIA model. Results: In the CIA model, we found that levels of tumor necrosis factor-alpha (TNF-a), interleukin (IL)-1, IL-6, and IL-17, as well as CICs, were elevated significantly. Moreover, concentrations of milk- or egg-specific IgG and IgE were enhanced strikingly in CIA rats. Conclusion: The results suggest that pathogenesis of RA correlates closely to increased egg- or milk-specific antibodies.

We report here the identification and characterization of STIP, a multi-domain nuclear protein that contains a G-patch, a coiled-coil, and several short tryptophan-tryptophan repeats highly conserved in metazoan species. To analyze their functional role in vivo, we cloned nematode stip-1 genes and determined the spatiotemporal pattern of Caenorhabditis elegans STIP-1 protein. RNA analyses and Western blots revealed that stip-1 mRNA was produced via trans-splicing and translated as a 95-kDa protein. Using reporter constructs, we found STIP-1 to be expressed at all developmental stages and in many tissue/cell types including worm oocyte nuclei. We found that STIP-1 is targeted to the nucleus and forms large polymers with a rod-like shape when expressed in mammalian cells. Using deletion mutants, we mapped the regions of STIP-1 involved in nuclear import and polymer assembly. We further showed that knockdown of C. elegans stip-1 by RNA interference arrested development and resulted in morphologic abnormalities around the 16-cell stage followed by 100% lethality, suggesting its essential role in worm embryogenesis. Importantly, the embryonic lethal phenotype could be faithfully rescued with Drosophila and human genes via transgenic expression. Our data provide the first direct evidence that STIP have a conserved essential nuclear function across metazoans from worms to humans.

Rhesus (Rh) proteins share a conserved 12-transmembrane topology and specify a family of putative CO 2 channels found in diverse species from microbes to human, but their functional essentiality and physiological importance in metazoans is unknown. To address this key issue and analyze Rh-engaged physiologic processes, we sought to explore model organisms with fewer Rh genes yet are tractable to genetic manipulations. In this article, we describe the identification in nematodes of two Rh homologues that are highly conserved and similar to human Rh glycoproteins, and we focus on their characterization in Caenorhabditis elegans . RNA analysis revealed that CeRh1 is abundantly expressed in all developmental stages, with highest levels in adults, whereas CeRh2 shows a differential and much lower expression pattern. In transient expression in human cells, both CeRh1 and CeRh2-GFP fusion proteins were routed to the plasma membrane. Transgenic analysis with GFP or LacZ-fusion reporters showed that CeRh1 is mainly expressed in hypodermal tissue, although it is also in other cell types. Mutagenesis analysis using deletion constructs mapped a minimal promoter region driving CeRh1 gene expression. Although CeRh2 was dispensable, RNA interference with CeRh1 caused a lethal phenotype mainly affecting late stages of C. elegans embryonic development, which could be rescued by the CbRh1 homologue from the worm Caenorhabditis briggsae . Taken together, our data provide direct evidence for the essentiality of the CeRh1 gene in C. elegans , establishing a useful animal model for investigating CO 2 channel function by cross-species complementation.