IgE Antibody Responses Research Articles

Mucosal delivery of allergen peptides expressed by Lactococcus lactis inhibit allergic responses in a BALB/c mouse model.

Allergen-specific immunotherapy (SIT) is considered to be the only curative treatment of allergy, but its safety is always affected by immunologic properties and quality of allergen. Recombinant allergen derivative could be a potential therapeutic strategy, but clinical studies showed that macromolecular derivatives could not avoid T cell-mediated side effects. In this study, five Der p2-derived peptides (DPs) containing major T cell epitopes of Der p2 were first artificially synthesized. Compared with Der p2 macromolecular derivative DM, these DPs not only fully eliminated IgE-binding capacity but also reduced T cells reactivity, suggesting these DPs could be better therapeutic molecules. For their application in vivo, Lactococcus lactis was engineered to express these DPs, and their protective effects were evaluated in BALB/c mice models. Western blot showed that all DPs could be produced in the recombinant strains. Mucosal delivery of these strains could inhibit Der p2-induced allergic responses in Der p2-sensitized mice, characterized by a reduction in specific IgE antibody and lung inflammatory responses. These protective effects were associated with an increase of specific IgG2a in serum and regulatory T cells in the mesenteric lymph nodes. On the whole, the suppressive effect induced by the DP mixture could be better than single DP, but a bit weaker than DM. These DPs could be promising candidate molecules for active vaccination and induction of tolerance, and thus promote the development of non-allergenic peptide in the treatment and prevention of allergy.

IgE responses to exogenous and endogenous allergens in atopic dermatitis patients under long-term systemic cyclosporine A treatment.

Atopic dermatitis (AD) patients mount IgE antibody responses to a variety of environmental allergens and also to autoantigens. We analyzed serum samples from four AD patients who had received oral cyclosporine A (CyA) treatment for up to 17 months regarding IgE autoreactivity to nitrocellulose‐blotted human epithelial cell extracts and IgE levels to environmental allergens by quantitative ImmunoCap measurements. Skin inflammation was assessed by SCORAD. During full‐dose treatment, a strong reduction in T‐cell‐mediated skin symptoms was observed which reappeared when CyA treatment was reduced or stopped. The intensity of IgE autoreactivity seemed to follow skin inflammation as it was reduced during full‐dose treatment and increased upon inflammation. Interestingly, IgE levels to exogenous allergens were boosted by allergen exposure, declined thereafter, and seemed to be unaffected by CyA. Our data thus indicate that allergen‐specific IgE production is boosted by allergen contact and cannot be reduced by CyA‐mediated T‐cell suppression.

Red meat allergic patients have a selective IgE response to the α-Gal glycan.

Galactose-α-1,3-galactose (α-Gal) is a mammalian carbohydrate with significance in a novel type of food allergy. Patients with IgE against α-Gal report severe allergic symptoms 3-6 h after consumption of red meat. We investigated whether IgE from red meat allergic patients recognizes other mammalian glycans than α-Gal or glycans from the plant kingdom and insects of importance in allergy. We found that none of the 24 red meat allergic patients investigated had an IgE antibody response against the other abundant mammalian glycan N-glycolylneuraminic acid or against cross-reactive carbohydrate determinants from plant or venom sources (nCup a 1, nArt v 1, and MUXF3). Deglycosylation of an α-Gal-containing protein, bovine thyroglobulin, significantly reduced the IgE response. In conclusion, we show that red meat allergic patients have a selective IgE response to the α-Gal glycan found in red meat. Other common glycans reactive in allergic disease are not targets of red meat allergic patients' IgE.

Molecular Allergy Diagnostics: Analytical Features That Support Clinical Decisions.

Application of purified native and recombinant allergenic molecules into IgE antibody assays can improve analytical sensitivity and specificity for selected allergen specificities. They enhance analytical sensitivity by allowing assays to detect IgE antibodies with a lower limit of quantification (LoQ) to missing or poorly represented allergens in diagnostic extracts that are commonly used in vivo and in vitro. Use of selected allergenic molecules can help improve the clinician's prediction of the risk of a serious allergic reaction to stable allergens. They can provide diagnostic information to determine if a provocation challenge (e.g., oral food challenge) is indeed mandatory or not necessarily needed to support the final diagnostic decision. Suspected cross-reactivity based on the clinical history can be adjudicated by analyzing IgE antibodies to allergenic molecules from cross-reactive protein families. Finally, genuine primary sensitization can be identified by IgE antibody responses that are measured to selected allergenic molecules which are present in only one particular allergen source. After allergen-specific IgE detection, careful interpretation is required by the physician who knows the patient's history. Applying single allergen molecules, positive IgE antibody results are still only relevant in the case of corresponding objective symptoms. Subsequently, clinical relevance of such an IgE antibody test result must be determined by the clinician and not by the test itself. Because of their comprehensive nature, allergen extracts will remain the principal allergen source for diagnostic in vivo and in vitro assays of IgE antibody for many years. Judicious use of individual allergenic molecules in serum IgE assays may provide their most cost effective and efficient application for establishing a definitive diagnosis of human allergic disease.

Poor association of allergen-specific antibody, T- and B-cell responses revealed with recombinant allergens and a CFSE dilution-based assay.

BackgroundThe adaptive immunity underlying allergy comprises two components, the allergen‐specific antibody (i.e. IgE, IgG) and the T‐cell response. These two components are responsible for different disease manifestations and can be targeted by different therapeutic approaches. Here, we investigated the association of allergen‐specific antibody and T‐ as well as B‐cell responses in pollen‐allergic patients using recombinant (r) major birch pollen allergen rBet v 1 and major timothy grass pollen allergen rPhl p 5 as defined antigens.MethodsAllergen‐specific IgE and IgG antibody responses were determined by ELISA, and allergen‐specific T‐ and B‐cell responses were measured in peripheral blood mononuclear cells using a carboxyfluorescein‐diacetate‐succinimidylester (CFSE) dilution assay.ResultsCFSE staining in combination with T‐cell‐ and B‐cell‐specific gating allowed discriminating between allergen‐specific T‐cell and B‐cell responses. Interestingly, we identified patients where mainly T cells and others where mainly B cells proliferated in response to allergen stimulation. No association between the level of allergen‐specific Ig responses and B‐ or T‐cell proliferation was observed.ConclusionPurified recombinant allergens in conjunction with CFSE staining allow the dissection of allergen‐specific B‐ and T‐cell responses. The dissociation of allergen‐specific antibody, and B‐ and T‐cell responses may explain the occurrence of selective IgE‐ and T‐cell‐mediated manifestations of allergic inflammation and may be important for the development of diagnostic and therapeutic strategies selectively targeting B cells and T cells.

IgE Antibody Detection and Component Analysis in Patients with Eosinophilic Esophagitis

Although IgE antibodies to cow's milk and wheat are common in patients with eosinophilic esophagitis (EoE), titers are low and responses to diet are not dependent on having IgE antibodies. To better define specific IgE antibody responses to foods, focusing on those foods that appear to play a role in EoE. Adult (n = 46) and pediatric (n = 51) patients with EoE were recruited for skin prick testing and serum measurement (whole and diluted) of IgE antibodies specific for aeroallergens, food extracts, and component allergens by ImmunoCAP. Immuno Solid-phase Allergen Chip analysis was also used to measure the specificity of IgE antibodies to 112 allergen molecules. In adults and children, there was a higher prevalence of sensitization to food extracts by ImmunoCAP than by skin prick testing. Using Immuno Solid-phase Allergen Chip to assess the specificity of IgE antibodies to 112 allergen molecules, we found that results for food allergens were mostly negative. In contrast, ImmunoCAP assays for specific milk allergens gave positive IgE antibody results in 31 of 34 sera. The correlations between specific IgE antibody to Bos d 4 or Bos d 5 and milk extract were strong (R = 0.89 and 0.76, respectively; P < .001). The evidence that IgE antibodies to foods were directed at minor components of the extracts was further supported by measurements on diluted sera. The IgE responses in cow's milk-sensitized patients with EoE are frequently to whey proteins Bos d 4 and Bos d 5, minor components of the extract. These IgE assays may be able to identify the proteins that are relevant to EoE even though IgE is not the primary mechanism.

IgE Anti-LJM11 Sand Fly Salivary Antigen May Herald the Onset of Fogo Selvagem in Endemic Brazilian Regions

IgE Anti-LJM11 Sand Fly Salivary Antigen May Herald the Onset of Fogo Selvagem in Endemic Brazilian Regions

Peak TMA Specific IgG Responses May Predict the Likelihood of TMA Exposed Workers Developing TMA Specific IgE Responses

Workplace exposure to Trimellitic Anhydride (TMA) can elicit specific IgG and IgE antibody responses leading to occupational asthma (OA). An immuno-surveillance program to identify and remove workers with TMA-specific serum IgE, who are at risk for OA, has been previously developed. This purpose of this study was to determine whether the kinetics of specific antibody responses can differentiate workers who only develop TMA specific IgG from those that progress to specific IgE.

Carbohydrates as allergens.

Complex carbohydrates are effective inducers of Th2 responses, and carbohydrate antigens can stimulate the production of glycan-specific antibodies. In instances where the antigen exposure occurs through the skin, the resulting antibody production can contain IgE class antibody. The glycan-stimulated IgE may be non-specific but may also be antigen specific. This review focuses on the production of cross-reactive carbohydrate determinants, the recently identified IgE antibody response to a mammalian oligosaccharide epitope, galactose-alpha-1,3-galactose (alpha-gal), as well as discusses practical implications of carbohydrates in allergy. In addition, the biological effects of carbohydrate antigens are reviewed in setting of receptors and host recognition.

Staphylococcal enterotoxin B induces specific IgG4 and IgE antibody serum levels in atopic dermatitis.

Atopic dermatitis (AD) is a chronic recurrent inflammatory disease, with prevalence of about 10-20% in children and 1-3% in adults. Staphylococcus aureus is present in 80-100% of skin from atopic patients and is related to worsening of the disease by the action of enterotoxins. The aim of this study was to evaluate the profile of anti-Staphylococcus aureus enterotoxin B (SEB) antibody isotypes and IgG subclass levels in adult AD. We selected 38 patients with AD, diagnosed by Hanifin and Rajka's criteria, aged between 18 and 65, and 26 healthy controls (HC). The severity of the disease was established according to the Eczema Area and Severity Index and patients graded as mild (28%), moderate (58%), and severe (14%). Sera were assessed for IgG subclasses, IgA, IgM, and IgE against SEB by ELISA. Elevated circulating IgE and IgG4 anti-SEB antibody levels associated with decreased IgA and IgM levels were detected in patients with AD, when compared to HC individuals. The severity of AD was related to low IgG1 and IgG3 levels and a high IgE antibody response to SEB. Interestingly, absence of IgG4 response to SEB was lower in patients with AD (2.63%), when compared to controls (34.6%), while a similar absence was detected for IgG1 and IgE antibodies (AD, 23.3 and 18.4% vs. HC, 38.5 and 19.2%). Our findings evidenced a contributing role for IgG4 and IgE antibodies in AD pathogenesis, which are triggered by staphylococcal superantigens.

Oral Antihyperlipidemic Statin Agents Intake Attenuates Food Allergen Specific IgE Antibody Responses in Sensitized Mice

Oral Antihyperlipidemic Statin Agents Intake Attenuates Food Allergen Specific IgE Antibody Responses in Sensitized Mice

Diisocyanates, occupational asthma and IgE antibody: implications for hazard characterization.

Sensitization of the respiratory tract by chemicals resulting in rhinitis and asthma is an important occupational health issue. Occupational asthma is associated with significant morbidity and can be fatal. Tests for the identification and characterization of chemicals with the potential to cause sensitization of the respiratory tract are lacking. In spite of sustained interest there are no validated or widely accepted methods available, and this presents toxicologists with a considerable challenge. One important constraint on the development of appropriate testing strategies has been uncertainty and controversy about the immunological mechanisms through which chemicals may induce sensitization of the respiratory tract. By analogy with protein respiratory allergy it is legitimate to consider that IgE antibody-dependent mechanisms may play a pivotal role. However, although many aspects of chemical respiratory allergy are consistent with reactions caused by IgE antibody, uncertainty remains because among patients with occupational asthma caused by chemical respiratory allergens there are commonly a proportion, and sometimes a significant proportion, of subjects that lack detectable IgE antibody. Here we consider the relevance of IgE antibody responses for the development of a chemical respiratory allergy to diisocyanates. A case is made that IgE antibody responses are, either directly or indirectly, closely associated with occupational asthma to the diisocyanates (and to other chemical respiratory allergens). As such the argument is advanced here that IgE antibody represents an appropriate readout for the characterization of chemical respiratory allergens, and that uncertainty about mode of action should no longer represent a hurdle in the development of suitable test methods.

Persistence of IgE-associated allergy and allergen-specific IgE despite CD4+ T cell loss in AIDS.

The infection of CD4+ cells by HIV leads to the progressive destruction of CD4+ T lymphocytes and, after a severe reduction of CD4+ cells, to AIDS. The aim of the study was to investigate whether HIV-infected patients with CD4 cell counts <200 cells/µl can suffer from symptoms of IgE-mediated allergy, produce allergen-specific IgE antibody responses and show boosts of allergen-specific IgE production. HIV-infected patients with CD4 counts ≤200 cells/µl suffering from AIDS and from IgE-mediated allergy were studied. Allergy was diagnosed according to case history, physical examination, skin prick testing (SPT), and serological analyses including allergen microarrays. HIV infection was confirmed serologically and the disease was staged clinically. The predominant allergic symptoms in the studied patients were acute allergic rhinitis (73%) followed by asthma (27%) due to IgE-mediated mast cell activation whereas no late phase allergic symptoms such as atopic dermatitis, a mainly T cell-mediated skin manifestation, were found in patients suffering from AIDS. According to IgE serology allergies to house dust mites and grass pollen were most common besides IgE sensitizations to various food allergens. Interestingly, pollen allergen-specific IgE antibody levels in the patients with AIDS and in additional ten IgE-sensitized patients with HIV infections and low CD4 counts appeared to be boosted by seasonal allergen exposure and were not associated with CD4 counts. Our results indicate that secondary allergen-specific IgE production and IgE-mediated allergic inflammation do not require a fully functional CD4+ T lymphocyte repertoire.

Effect of extrusion processing on in vivo allergenicity of hazelnut in an adjuvant-free mouse model (HYP7P.313)

Abstract Life-threatening nut allergy is a growing public health problem in many countries including the USA. Causes underlying this alarming trend are incompletely understood and methods are urgently needed to prevent such immune reactions. Here, we tested the hypothesis that extrusion processing of hazelnuts will reduce in vivo allergenicity using an adjuvant-free mouse model of hazelnut allergy established in our lab. Groups of mice received transdermal exposure (TDE) to extrusion processed hazelnut protein (EHNP) versus raw hazelnut protein (RHNP) extract preparations. Mice were evaluated for systemic IgE antibody responses (sIgER), hypothermia shock response (HSR), and mucosal mast cell responses by measuring plasma mouse mast cell protease-1 (mMCP-1) levels. Results showed that EHNP elicited a reduced sIgER compared to RHNP after 4 TDE but similar responses after 5 TDE. However, EHNP induced less HSR compared to RHNP upon oral challenge. Both protein preparations induced similar HSR upon i.p., challenge. Finally, we measured plasma mMCP-1 levels after oral and i.p., injection challenges. We found that EHNP elicited reduced mMCP-1 response compared to RHNP upon both oral as well as i.p., challenges. This is the first study demonstrating the utility of a mouse model to evaluate the effect of food processing on in vivo food allergenicity in general and hazelnut in particular.

Delayed Anaphylaxis to Red Meat Masquerading as Idiopathic Anaphylaxis

Anaphylaxis is traditionally recognized as a rapidly developing combination of symptoms that often includes hives and hypotension or respiratory symptoms. Furthermore, when a specific cause is identified, exposure to this cause is usually noted to have occurred within minutes to 2 hours before the onset of symptoms. This case is of a 79-year-old woman who developed a severe episode of anaphylaxis 3 hours after eating pork. Before 2012, she had not experienced any symptoms after ingestion of meat products. Delayed anaphylaxis to mammalian meat has many contrasting features to immediate food-induced anaphylaxis. The relevant IgE antibody is specific for the oligosaccharide galactose-alpha-1,3-galactose, a blood group substance of nonprimate mammals. There is evidence from Australia, Sweden, and the United States that the primary cause of this IgE antibody response is tick bites. These bites characteristically itch for 10 days or more. Diagnosis can be made by the presence of specific IgE to beef, pork, lamb, and milk, and the lack of IgE to chicken, turkey, and fish. Skin prick tests (but not intradermal tests) generally are negative. Management of these cases, now common across the southeastern United States, consists of education combined with avoidance of both ingestion of red meat and further tick bites.

Linear versus conformational epitopes of three cow's milk allergens

Method Specific antibodies were raised in a Brown Norway (BN) rat model of food allergy. BN rats were dosed either (1) intraperitoneally (i.p.) with the purified native cow’s milk allergens with or without the use of Al(HO)3 as adjuvant or (2) orally with skimmed milk powder without the use of adjuvant. The specific IgG1 and IgE antibody responses were analysed against native and denatured allergens by means of different ELISAs.

Antibody response in naïve and sensitised goats infested by Sarcoptes scabiei

The purpose of this study was to characterize the IgG and IgE antibody responses in goats infested repeatedly with Sarcoptes scabiei . Ten goats purchased from scabies-free farms were infested with 2000 live mites on the auricles. Fifty days after the initial infestation, the goats were treated with ivermectin. After being completely recovered, the goats were reinfested then treated again at 50 days post infestation. Blood samples were collected at the time of the first infestation, then every 10 days afterwards for 270 days. Seroconversion for IgG took place after 30 days following the first infestation, whereas the maximum level of the specific IgG antibodies occurred after 50 days. Immunoblot analysis identified a number of antigens ( M r 180, 135, 43 and 38 KDa) that recognised by the IgG at 10 days and continuously recognised throughout the course of the multiple infestations. Being consistently recognised, those antigens should be essential in the development immunological diagnostic tests for scabies. The levels of scabies-specific IgE antibodies increased slowly during the first infestation and rapidly dropped following treatment of the animals with ivermectin. In the second and third infestations, however, the reaginic antibodies rose rapidly and with a grater level. On immunoblot analysis, at least 10 antigens ( M r 130, 72, 64, 58, 48, 44, 41, 39, 27 and 25 KDa) were observed to be recognised by the IgE present in the sera from scabies-infested animals. Since IgE response is considered to play a major role in the immune protection, those allergens, therefore, could be used as the main component of an anti-scabies vaccine. Key words: Sarcoptes scabiei , antibody, goats

Drug allergens and food—the cetuximab and galactose-α-1,3-galactose story

ObjectiveA novel form of food allergy has been described that initially became apparent from IgE reactivity with the drug cetuximab. Ongoing work regarding the etiology, distribution, clinical management, and cellular mechanisms of the IgE response to the oligosaccharide galactose-α-1,3-galactose (α-gal) is reviewed. Data SourcesBrief review of the relevant literature in peer-reviewed journals. Study SelectionStudies on the clinical and immunologic features, pathogenesis, epidemiology, laboratory evaluation, and management of IgE to α-gal are included in this review. ResultsRecent work has identified a novel IgE antibody response to the mammalian oligosaccharide epitope, α-gal, that has been associated with 2 distinct forms of anaphylaxis: (1) immediate-onset anaphylaxis during first exposure to intravenous cetuximab and (2) delayed-onset anaphylaxis 3 to 6 hours after ingestion of mammalian food products (eg, beef and pork). Study results have suggested that tick bites are a cause of IgE antibody responses to α-gal in the United States. Patients with IgE antibody to α-gal continue to emerge, and, increasingly, these cases involve children. Nevertheless, this IgE antibody response does not appear to pose a risk for asthma but may impair diagnostic testing in some situations. ConclusionThe practicing physician should understand the symptoms, evaluation, and management when diagnosing delayed allergic reactions to mammalian meat from IgE to α-gal or when initiating treatment with cetuximab in patients who have developed an IgE antibody response to α-gal.

Systemic and mucosal IgE antibody responses of horses to infection with Anoplocephala perfoliata

Infection of horses with Anoplocephala perfoliata induces a severe inflammatory reaction of the caecal mucosa around the site of parasite attachment adjacent to the ileocecal valve. Lesions show epithelial erosion or ulceration of the mucosa with infiltration by eosinophils, lymphocytes and mast cells leading to oedema, gross thickening and fibrosis of the caecal wall. Despite this evidence of an inflammatory reaction to A. perfoliata within the mucosa of the caecum there is little information about the nature of the local immune response to A. perfoliata. An ELISA which assays serum IgG(T) antibodies to A. perfoliata excretory/secretory antigens has been developed as a diagnostic test. However, the specificity of the ELISA remains sub-optimal and the role of other isotypes in the immune response to A. perfoliata has not been reported. This study measured IgA, IgE and IgG(T) antibody responses to A. perfoliata excretory/secretory antigens in sera of 75 horses presented for slaughter. The prevalence of A. perfoliata infection, as confirmed by the presence of parasites in the terminal ileum, caecum or proximal colon, was 55%. A. perfoliata-specific IgG(T) and IgE antibodies were significantly elevated in infected horses compared to controls; IgA antibodies were also detected but did not differ between infected and control horses. Diagnosis by serum IgG(T) ELISA had a sensitivity of 78% and a specificity of 80%, by comparison the serum IgE ELISA had a sensitivity of just 44% with a specificity of 82% and therefore did not provide an improved diagnostic test. Western blots with sera from infected horses demonstrated IgE-binding to at least 10 separate components of excretory/secretory (E/S) antigens. A similar pattern was also found with IgG(T). Around 30% of horses had high levels of serum IgE which bound fucose-containing carbohydrate antigens on the parasite surface but this was unrelated to the presence of A. perfoliata infection.Immunoperoxidase staining detected numerous IgE-positive cells within lymphoid follicles in the caecal mucosa close to the site of A. perfoliata attachment and quantitative RT-PCR detected high levels of IgE transcription in the caecal mucosa of all horses. Mucosal synthesis of antibodies was confirmed by the demonstration of A. perfoliata-specific IgG(T) and IgE in the supernatant of lamina propria explant cultures that discriminated clearly between infected and uninfected horses. We conclude that there is an active immune response to A. perfoliata within the caecal mucosa involving local production of both IgG(T) and IgE antibody isotypes; but it remains unclear whether this immune response can reduce or eliminate parasite burden.

Sensitization to food and inhalant allergens in relation to age and wheeze among children with atopic dermatitis

Atopic dermatitis (AD) is common in children; however, persistence of AD with or without asthma is less common. Longitudinal studies remain limited in their ability to characterize how IgE antibody responses evolve in AD, and their relationship with asthma. To use a cross-sectional study design of children with active AD to analyse age-related differences in IgE antibodies and relation to wheeze. IgE antibodies to food and inhalant allergens were measured in children with active AD (5months to 15years of age, n=66), with and without history of wheeze. Whereas IgE antibodies to foods persisted at a similar prevalence and titre throughout childhood, IgE antibodies to all aeroallergens rose sharply into adolescence. From birth, the chance of sensitization for any aeroallergen increased for each 12-month increment in age (OR≥1.21, P<0.01), with the largest effect observed for dust mite (OR=1.56, P<0.001). A steeper age-related rise in IgE antibody titre to dust mite, but no other allergen was associated with more severe disease. Despite this, sensitization to cat was more strongly associated with wheeze (OR=4.5, P<0.01), and linked to Fel d 1 and Fel d 4, but not Fel d 2. Comparison of cat allergic children with AD to those without, revealed higher IgE levels to Fel d 2 and Fel d 4 (P<0.05), but not Fel d 1. Differences in sensitization to cat and dust mite among young children with AD may aid in identifying those at increased risk for disease progression and development of asthma. Early sensitization to cat and risk for wheeze among children with AD may be linked to an increased risk for sensitization to a broader spectrum of allergen components from early life. Collectively, our findings argue for early intervention strategies designed to mitigate skin inflammation in children with AD.