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The specific detection of serum IgE antibodies specific to allergens (sIgE Abs) that can crosslink the plural high-affinity IgE receptor (FcεRIα) molecules on the surface of mast cells or basophils with a multivalent allergen can reduce the false-positive diagnoses observed in chemiluminescent and fluorescence enzyme immunoassays for type-I allergic patients. In this study, we detected sIgE Abs to the egg-allergen ovalbumin (OVA) and the wheat-allergen gluten in the sera of rats sensitized with each allergen using an amplified luminescence proximity homogeneous assay by crosslinking (AlphaCL). OVA and gluten were reacted with each sIgE Ab in the sera. Then, acceptor and donor beads labeled with the human FcεRIα were added to the reacted solution. The luminescence intensity for anti-OVA IgE Abs in the sera with the removal of IgG Abs was observed in five of seven (71.4%) of the sensitized rats, whereas no signals were observed in any of the unsensitized rats. The AlphaCL could also detect anti-gluten sIgE Abs in the sera of sensitized rats, but not of unsensitized rats. In conclusion, we successfully detected sIgE Abs in the sera of rats sensitized to two allergens using the AlphaCL. This detection method has the potential to be used as a new diagnostic tool for type-I allergic patients. [ABSTRACT FROM AUTHOR]

Immunoglobulin E (IgE)-mediated food allergies to wheat that develop after school age typically shows a type of wheat-dependent exercise-induced anaphylaxis (WDEIA). At present, avoidance of wheat products or postprandial rest after ingesting wheat is recommended for patients with WDEIA, depending on the severity of the allergy symptoms. ω5-Gliadin has been identified as the major allergen in WDEIA. In addition, α/β-, γ-, and ω1,2-gliadins, high and low molecular weight-glutenins, and a few water-soluble wheat proteins have been identified as IgE-binding allergens in a small proportion of patients with IgE-mediated wheat allergies. A variety of approaches have been manufactured to develop hypoallergenic wheat products that can be consumed by patients with IgE-mediated wheat allergies. In order to analyze such approaches, and to contribute to the further improvement, this study outlined the current status of these hypoallergenic wheat productions, including wheat lines with a reduced allergenicity that are mostly constructed for the patients sensitized to ω5-gliadin, hypoallergenic wheat by enzymic degradation/ion exchanger deamidation, and hypoallergenic wheat by thioredoxin treatment. The wheat products obtained by these approaches significantly reduced the reactivity of Serum IgE in wheat-allergic patients. However, either these were not effective on some populations of the patients, or low-level IgE-reactivity to some allergens of the products was observed in the patients. These results highlight some of the difficulties faced in creating hypoallergenic wheat products or hypoallergenic wheat lines through either traditional breeding or biotechnology approaches in developing hypoallergenic wheat completely safe for all the patients allergic to wheat. [ABSTRACT FROM AUTHOR]

The early ingestion of food can prevent the onset of food allergy related to inducing oral tolerance (OT). We developed the Hokushin wheat line as a hypoallergenic wheat (1BS-18H) lacking ω5-gliadin, a major allergen of wheat-dependent exercise-induced anaphylaxis (WDEIA). The 1BS-18H wheat had lower ability of sensitization for ω5-gliadin compared with Hokushin wheat. Here, we evaluated the induction of OT to gluten and ω5-gliadin by the early consecutive ingestion of 1BS-18H gluten using a rat model of wheat allergy. Rats were subcutaneously immunized with commercial gluten or native ω5-gliadin following the daily oral administration of gluten. The daily oral administration of 1BS-18H gluten for 5 days before immunization suppressed the increase in gluten- or ω5-gliadin-specific IgE and IgG1 antibodies induced by immunization to a level similar to Hokushin gluten. Intravenous challenge with gluten or ω5-gliadin did not decrease the rectal temperature in rats with OT induced by 1BS-18H or Hokushin gluten, although it was decreased in non-OT rats. In conclusion, the early consecutive ingestion of 1BS-18H wheat before sensitization induced OT to gluten and ω5-gliadin. These findings support the benefit of 1BS-18H wheat to prevent wheat allergy including WDEIA by consecutive ingestion in humans. [ABSTRACT FROM AUTHOR]

Keywords: exercise; gliadin; non-steroidal anti-inflammatory drugs; prostaglandin; wheat-dependent exercise-induced anaphylaxis EN exercise gliadin non-steroidal anti-inflammatory drugs prostaglandin wheat-dependent exercise-induced anaphylaxis 359 361 3 03/15/23 20230301 NES 230301 Key messages Bread ingestion combined with exercise or aspirin increased the serum level of wheat gliadins. We measured the blood gliadin levels in patients with WDEIA during a challenge test, using a highly sensitive enzyme-linked immunosorbent assay (ELISA) that can specifically detect wheat gliadin.[[2]] As a result, the blood gliadin level increased preceding the allergic symptoms when induced by the combination of wheat ingestion and exercise, while serum gliadin was not detected or remained at a very low level in the case of the wheat ingestion alone. Blood gliadin levels were elevated for 15-120 min after gluten ingestion; however, no enhancing effects were found for aspirin, alcohol, or exercise on blood gliadin levels. [Extracted from the article]

Shrimp is a causative food that elicits food-dependent exercise-induced anaphylaxis (FDEIA). In this study, we sought to identify IgE-binding allergens in patients with shrimp-FDEIA. Sera were obtained from eight patients with shrimp-FDEIA and two healthy control subjects. Proteins were extracted from four shrimp species by homogenization in Tris buffer. Immunoblot analysis revealed that IgE from patient sera bound strongly to a 70-kDa and a 43-kDa protein in a preparation of Tris-soluble extracts from Litopenaeus vannamei. Mass spectrometry identified the 70-kDa and 43-kDa proteins as a P75 homologue and fructose 1,6-bisphosphate aldolase (FBPA), respectively. To confirm that the putative shrimp allergens were specifically recognized by serum IgE from shrimp-FDEIA patients, the two proteins were purified by ammonium sulfate precipitation followed by reversed-phase HPLC and/or anion-exchange hydrophobic interaction chromatography and then subjected to immunoblot analysis. Purified P75 homologue and FBPA were positively bound by serum IgE from one and three, respectively, of the eight patients with shrimp-FDEIA, but not by sera from control subjects. Thus, P75 homologue and FBPA are identified as IgE-binding allergens for shrimp-FDEIA. These findings could be useful for the development of diagnostic tools and desensitization therapy for shrimp-FDEIA patients. [ABSTRACT FROM AUTHOR]

Background: The effect of oral immunotherapy (OIT) on wheat allergy is promising in terms of the potential to obtain desensitization; however, the frequency of exercise‐induced allergic reactions on desensitization (EIARDs) and the associated risk factors remain to be determined. Methods: Twenty‐five patients underwent rush OIT for wheat allergy, and 21 achieved the full‐dose intake of wheat products (5 g of wheat protein). Exercise‐provocation tests were repeatedly performed after the ingestion of a full‐dose wheat product. The time‐course of the levels of the specific IgEs (sIgE) to wheat extract, total gliadin, deamidated gliadin, recombinant gliadin components (α/β–, γ– and ω–5–), and glutenin (high and low molecular weight) components was analyzed using ImmunoCAP®, ELISA, or IgE immunoblotting. Results: Fourteen patients (66.7%) were diagnosed as EIARD+, which remained 5 years after rush OIT in 11 patients (52.4%). There were no differences in the clinical backgrounds of the EIARD+ and EIARD− patients. However, EIARD+ patients showed significantly higher sIgE levels to all gliadin and glutenin components than EIARD‐ patients before OIT. The sIgE levels to each component decreased equally after 1 and 2 years of OIT. On IgE immunoblotting, sera from all patients reacted to the multiple gluten bands, and some reacted to the water‐soluble bands. The intensity of all IgE‐reactive bands also became equally lighter after OIT. Conclusions: EIARDs were frequently observed and remained for a long period after successful OIT for wheat allergy. None of the specific wheat components were found to contribute to EIARDs. [ABSTRACT FROM AUTHOR]

Enhancement of oral absorption of food allergens by non-steroidal anti-inflammatory drugs (NSAIDs), especially aspirin, is considered an exacerbating factor in the development of food allergies. In this study, we examined the effect of aspirin on oral sensitization to and absorption of the egg-white allergen ovalbumin (OVA) in rats. The absorption of OVA was evaluated by measuring the plasma concentration of OVA after oral administration by gavage. To evaluate oral sensitization to OVA, plasma levels of immunoglobulin (Ig) E and IgG1 antibodies (Abs) specific to OVA were determined by enzyme-linked immunosorbent assay after initiation of sensitization. High-dose aspirin (30 mg/kg) increased oral OVA absorption and plasma levels of OVA-specific IgE and IgG1 Abs compared with those observed in vehicle-treated rats. In contrast, low-dose aspirin (3 mg/kg) exerted no changes in either absorption or sensitization. Spermine, an absorption enhancer, increased the oral absorption of OVA to nearly the same extent as high-dose aspirin, whereas the plasma levels of OVA-specific IgE and IgG1 Abs exhibited no significant differences between spermine- and vehicle-treated rats. Among the NSAIDs, diclofenac and indomethacin increased sensitization to OVA, similar to high-dose aspirin, but meloxicam exerted no effects on Ab levels. In conclusion, we showed that high-dose aspirin enhanced oral sensitization to OVA. Our study suggests that enhanced oral sensitization to OVA cannot be ascribed to increased absorption of OVA from the intestinal tract. Although the mechanisms underlying this enhancement of sensitization are still controversial, our study suggests that modification of cytokine production due to impairment of the intestinal barrier function and inhibition of cyclooxygenase-1 activity by aspirin may be involved. [ABSTRACT FROM AUTHOR]

Background: Pancreaticobiliary maljunction and intrahepatic gallstones are at a high risk for biliary malignancy. Lysophosphatidylcholine (LPC) is increased in the bile of these patients, and we have previously reported that LPC‐induced cytotoxicity causes senescence‐associated secretory phenotype (SASP) in cholangiocytes. We aimed to determine the protective effect of phosphatidylcholine (PC) on LPC‐induced cholangiocyte cytotoxicity. Methods: MMNK‐1, a human immortalized cholangiocyte cell line was treated with LPC with or without PC. To assess the biological effects of SASP components on cholangiocarcinoma, HuH28 and HuCCT1 (human cholangiocarcinoma cell lines) were cultured in the conditioned media where MMNK‐1 cells treated with LPC. Results: The presence of PC reduced reactive oxygen species generation and oxidative DNA damage in MMNK‐1 treated with LPC. Moreover, SA‐β‐gal activity was markedly downregulated by PC. The secretion of SASP components, including interleukin (IL)‐8, IL‐6, and C‐C motif chemokine ligand 2 was also substantially reduced in the presence of PC. Cellular proliferation and migration were enhanced in HuCCT1 and HuH28 cells when cultured in the conditioned media, and these observations were suppressed by simultaneous addition of PC. Conclusion: PC protects cholangiocytes against LPC‐induced cytotoxicity and cellular senescence, suggesting its potential as a target for inhibiting LPC‐related carcinogenesis and its promotion. [ABSTRACT FROM AUTHOR]

Aim: Rho‐kinase (ROCK) inhibitor could ameliorate liver fibrosis by suppressing hepatic stellate cell (HSC) activation. However, because systemic administration of ROCK inhibitor causes serious adverse effects, we developed a drug delivery system selectively delivering ROCK inhibitor to HSCs. Here, we examined whether our developed vitamin A (VA)‐coupled liposomal ROCK inhibitor reduced liver fibrosis in rats without causing systemic adverse effects. Methods: LX‐2 HSCs were analyzed for morphological changes and the expression of profibrotic proteins. The inhibitory effects of VA‐coupled liposomal ROCK inhibitor on liver fibrosis were confirmed in a rat model of liver fibrosis induced by i.p. injection of carbon tetrachloride. The degree of liver fibrosis, biochemical changes, and survival rates were also investigated. Results: Vitamin A‐coupled liposomal ROCK inhibitor had an effect at approximately 1/100 the amount of the free ROCK inhibitor for inhibiting the activation of LX‐2 cells and caused significant decreases in the expression levels of α‐smooth muscle actin (SMA) and transforming growth factor (TGF)‐β1. The degree of liver fibrosis was suppressed by treatment with VA‐coupled liposomal ROCK inhibitor, and the expression of α‐SMA and TGF‐β1 in liver tissues was also significantly suppressed. In addition, serum levels of alanine aminotransferase and hyaluronic acid were significantly reduced, and there was no decline in kidney function, which has been noted as a systemic adverse effect of ROCK inhibitor. Furthermore, VA‐coupled liposomal ROCK inhibitor improved survival rates in rats with liver fibrosis. Conclusion: Vitamin A‐coupled liposomal ROCK inhibitor efficiently suppressed liver fibrosis without causing systemic adverse effects. [ABSTRACT FROM AUTHOR]

Background: Aspirin (ASP)-facilitated absorption of ingested allergens is considered an exacerbating factor in the development of food allergy. Sodium cromoglycate (SCG) is used for the treatment of atopic dermatitis with food allergy, but the efficacy of SCG in ASP-exacerbated food-allergy reactions is unclear. In this study, we evaluated the effect of SCG on ASP-exacerbated food-allergic reactions, as well as allergen absorption, in egg-allergic model rats. Methods: Plasma concentrations of ovalbumin (OVA) and fluorescein isothiocyanate-labeled dextran (FD-40), a marker for nonspecific-absorption pathways, were measured after oral administration of mixtures of OVA and FD-40 in OVA-unsensitized and OVA-sensitized rats. IgE-mediated allergic reactions were evaluated by measuring changes in rectal temperature and Evans blue dye (EBD) extravasation in the intestine and liver after oral challenge with OVA. The effects of ASP and SCG on such absorption and allergic reactions were also evaluated kinetically. Results: In OVA-sensitized rats, plasma concentrations of OVA and FD-40 were significantly higher than those in unsensitized rats after oral administration. ASP increased the intestinal absorption of OVA and FD-40 via the paracellular pathway, and a lower rectal temperature and higher EBD extravasation were detected in the intestine and liver of OVA-sensitized rats. SCG ameliorated these ASP-facilitated absorptions and allergic reactions in a dose-dependent manner. In particular, high-dose SCG (195.2 μmol/kg) completely inhibited these absorptions and reactions. Conclusion: SCG can prevent ASP-exacerbated allergic reactions in patients with food allergy resulting from inhibition of increases in allergen absorption. © 2015 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Atopic dermatitis (AD) is a chronic inflammatory skin disease characterized by severe itching, erythema and edema resistant to anti-histamine therapy. Vascular endothelial growth factor (VEGF) is a potent agent that causes hyperpermeability of blood vessels and endothelial cell proliferation, and might be involved in the persisting erythema and edema in AD. In this study, we used extraction of stratum corneum with physiological saline to detect VEGF produced in the lesions of AD. Biological activity of VEGF was assayed by proliferation of cultured human umbilical vein endothelial cells in vitro. As a result, we found that the amount of VEGF produced in lesional scales was approximately 25 times higher than that in normal stratum corneum. Moreover, VEGF 121 isoform that exclusively induces hyperpermeability of blood vessels was a predominant component in the lesional scales suggesting that this factor plays an important role in the persisting erythema and edema in the AD lesions. [ABSTRACT FROM AUTHOR]

Shrimp is known to be the most common causative agent in seafood allergy. Patients with shrimp allergy often exhibit allergic symptoms to a variety of seafoods such as crabs and clams. We experienced a 14-year-old girl with shrimp allergy who developed oral swelling and pain accompanied with an uncomfortable feeling after ingestion of scallops followed by intensive exercise. Laboratory investigation showed that she had serum immunoglobulin (Ig)E molecules reacting with several kinds of crustaceans and mollusks, including shrimp, crab and scallops. Immunoblotting revealed that her serum IgE reacted with the 38 kDa bands for shrimp, crab and scallops, suggesting that tropomyosin was the major allergen. Dot-blot inhibition analysis showed a cross-reactivity among shrimp, crab and scallops. We conclude that the cross-reactivity of IgE in this patient resulted from the high homology of tropomyosins. [ABSTRACT FROM AUTHOR]