Histamine content does not influence the tolerance of wine in normal subjects

Histamine has been incriminated as having a responsibility for intolerance reaction to wines. We have made a study by double blind oral provocation test to find the effect of ingestion of a histamine-rich (22.8 mg.l-1) and a histamine free wine in eight healthy subjects. Blood samples were taken at 0, 10, 30 and 45 minutes after ingestion of the wine for measurement of plasma histamine and methylhistamine. Urines were collected 5 hours before and 5 hours after ingestion for measurement of urinary methylhistamine. No subject presented a reaction of intolerance after ingestion of wine rich or poor in histamine. No change in plasma histamine and plasma and urinary methylhistamine was seen. This study shows that the amount of histamine in wine has no clinical or biological effect in healthy subjects, and this emphasized the efficiency in man of the systems for degradation of histamine that is absorbed by the alimentary tract.

[Hyperglobulinemia E syndrome with recurrent infections (Job's syndrome)]

INTRODUCTION

To provide definition and nosology of hyperimmunoglobulinemia E previously termed Job's syndrome or Buckleys' syndrome in the literature. Generalization of IgE dosages makes it more commonly diagnosed, though sometimes diagnosis may not be accurate.

CURRENT KNOWLEDGE AND KEY POINTS

The clinical picture is dominated by recurring cutaneous and visceral bacterial infections, particularly infections due to staphylococci, and severe generalized eczema, which may be associated with osteoporosis. Biochemistry includes a high level of total and specific IgE and immunological abnormalities dominated by frequent absence of immune antibodies to staphylococci and disorders of neutrophil chemotaxis. Current pathogenic studies show dysregulation of TH1 and TH2 lymphocytes in favor of TH2 activation with depressed TH1 activation, leading to an imbalance in cytokine synthesis.

FUTURE PROSPECTS AND PROJECTS

New therapeutical possibilities with alpha and gamma interferon.

Food hypersensitivity in children: clinical aspects and distribution of allergens

The aims of this work were to investigate, in children and adolescents, the clinical aspects of food hypersensitivity and the distribution of allergens, in a prospective and descriptive study. Five hundred and forty-four pediatric cases from a series of 703 patients with food allergies, confirmed by food challenge, were studied. Their clinical characteristics and the distribution according to allergen were investigated. There was a family history of atopic disease in 70.5% of patients. Atopic dermatitis was the main symptom (275/544; 50.5% of patients), followed by urticaria and angio-edema (165/544; 30%). There was asthma in 8.6% of patients (47 children) and anaphylaxis in 4.5% (27 patients). The rarest signs were rhinitis (n=2; 0.3%), oral allergy syndrome (n=8; 1.4%), and gastrointestinal signs (n=11; 2%). Five allergens accounted for 78% of food hypersensitivity. These allergens were: eggs (36%), peanuts (24%), cow's milk (8%), mustard (6%), and cod (4%). Peanut was the most common allergen for children over the age of 3 yr. In this selected population, sensitivity of individuals to more than three foods was unusual (5%). Atopic dermatitis was the main symptom of food allergy in children. The symptoms changed over time, with respiratory disorders, oral allergy syndrome and ocular problems occuring later. Anaphylaxis also occured mostly in older children. Five allergens were responsible for more than three-quarters of food allergies in children. However, the number of allergens implicated was higher for the group of children over the age of 6 yr than for younger children.

Human basophil activation measured by CD63 expression and LTC4 release in IgE-mediated food allergy

BACKGROUND

IgE-dependent basophil activation induced by an allergen elicit the release of LTC4 and the expression of the CD63 membrane marker.

OBJECTIVE

The aim of this study was to check if flow cytometric analysis of basophil activation could be applied to food allergy diagnosis and if this method paralleled LTC4 release.

METHODS

Patients were selected by the clinical history, skin tests, and provocation tests. Basophil activation induced by food extracts was studied in 24 control subjects and in 27 patients having a food allergy by LTC4 release test (LRT) and by flow cytometric anti-IgE+, CD63 + cell counting (BAT = basophil activation test). In case of negative anti-IgE response a passive blood donor basophil passive sensitization step was added to LRT and BAT. Leucocyte histamine release test was performed in 11 patients.

RESULTS

Basophil activation test was positive in 18/31 cases and LRT in 22/34 cases for food-allergic patients and, respectively, in 1/33 and 1/35 cases for the controls. A correlation was observed between specific IgE, BAT, and LRT. Basophil activation test and LRT performed after passive sensitization had an excellent sensitivity only for specific IgE levels ranging between 3.5 and 35 KU/L.

CONCLUSION

The present study shows that allergen-induced LTC4 release and anti-IgE, antiCD63 bicolor flow cytometric analysis of basophil activation may be used for food allergy diagnosis. Both tests have a good sensitivity and specificity. Basophil activation test and LRT are more efficient than histamine release test in case of high spontaneous histamine release, frequently observed in case of food allergy.

Food allergy to peanuts in France--evaluation of 142 observations

BACKGROUND

The increase in frequency of peanut allergy and fatal cases have been reported.

OBJECTIVES

The objective of this study is to document the severity of food allergy to peanuts by evaluating the reactive dose of peanuts and to search for the role of peanut oil.

METHODS

This study is carried out on the basis of 142 observations collected according to the same diagnostic methodology in two allergy centres in France. Skin-prick-tests were performed with peanut powder, peanut oil and peanut oil proteinic extract. Labial provocation tests were performed on 121 patients. The reactive dose of peanuts and the role of peanut oil were determined by standardized oral provocation tests in 50 and 62 patients respectively. The data are computerized and the data bank includes 509 food allergic patients.

RESULTS

Allergy to peanuts represents 28% of food allergies and occurs under 1 year of age in 46% of cases, under 15 years of age in 93%. The clinical features were atopic dermatitis (40%), angioedema (37%), asthma (14%), anaphylactic shock (6%) and digestive symptoms (1.4%). The specific IgE were class 3 or higher in 80% of cases. The total reactive dose was less than 100 mg in 25% of cases, from 100 mg to 1 g in 62.5%. All patients reacted to a dose of less than 7.1 g. The threshold of peanut reactivity was lower than the threshold of egg reactivity. An allergy to peanut oil was demonstrated in 14 patients.

CONCLUSION

The severity of peanut allergy and the early onset of the occurrence of this allergy is documented. The role of residual allergenic proteins in peanut oil is established by positive skin-prick tests to proteic extracts from peanut oil and by double-blind placebo-controlled challenges to peanut oil. The increased consumption of allergens in the form of peanut oil and fats can contribute to the occurrence or persistence of symptoms and may be suspected to increase the risk of sensitisation.

Isolation and characterization of proteic allergens in refined peanut oil

Allergic reactions to peanut oil are very much debated, even if the responsibility of peanut oil has been evoked in several cases of adverse reactions, including death related to severe asthma. The aim of the present study was to investigate the presence of allergenic proteins in peanut oil. Proteins were extracted from commercial refined peanut oil, with a relative content in the order of 0.1-0.2 microg per g of oil, and molecular sizes ranging from 14 up to 76kDa in SDS-PAGE. Eight protein bands were systematically observed in crude, neutralized and refined oils, with a molecular mass ranging from approximately 14 to 76 kDa, including one at 18 kDa which was identified by Western blot performed with serum from two allergic patients. The protein extract gave positive IgE-RIA with patient sera, positive in vitro leucocyte histamine release tests and positive skin-prick tests in allergic patients. The allergenic protein was purified by HPLC and [125I] iodide-labelled. It had an isoelectric point at 4.5 in isoelectrofocusing. In conclusion, we have demonstrated the presence of allergenic proteins in crude and refined peanut oil. These proteins are the same size as two allergens previously described in peanut protein extracts.

[Masked and labelled food allergens]

Several food proteins are used as food additives or may be contained in foods as contaminants. These masked allergens are at high risk of inducing severe clinical reactions: acute asthma, laryngeal angioedema, anaphylactic shock or even death. The present regulation requires labelling only if the level of food ingredients is superior to 25% of the final product. Several immunologic methods can detect low levels of proteins, equal or inferior to 2%. However a level of 1% or less may be noxious, suggesting a need for a specific line of food products which could be guaranteed free of ... and which might be recommended to patients with food allergy.

Modifications of allergenicity linked to food technologies

The prevalence of food allergies (FA) has increased over the past fifteen years. The reasons suggested are changes in dietary behaviour and the evolution of food technologies. New cases of FA have been described with chayote, rambutan, arguta, pumpkin seeds, custard apple, and with mycoproteins from Fusarium.... Additives using food proteins are at high risk: caseinates, lysozyme, cochineal red, papaïn, alpha-amylase, lactase etc. Heating can reduce allergenicity or create neo-allergens, as well as storage, inducing the synthesis of allergenic stress or PR proteins. Aeroallergens (miles, moulds) contaminate foods and can induce allergic reactions. Involuntary contamination by peanut proteins on production lines is a problem which is not yet solved. Genetically modified plants are at risk of allergenicity, requiring methodological steps of investigations: the comparison of the amino-acid sequence of the transferred protein with the sequence of known allergens, the evaluation of thermo degradability and of the denaturation by pepsin and trypsin are required, as well as the study with sera from patients allergic to the plant producing the gene. The combination of enzymatic hydrolysis, heating, or the development of genetically modified plants may offer new alternatives towards hypoallergenic foods (57 references).

Recognition of an extensive range of IgE-reactive proteins in cod extract

Allergy to fish is one of the most common food allergies. Gad c 1 is the only fish allergen which has been purified and characterized. Other allergens have been detected by Western blot in cod extracts. We have now improved the Western-blot procedure in order to characterize fish IgE-reactive proteins from extracts prepared under different conditions: pre-rigor mortis and post-rigor mortis, EDTA addition or not, and DEAE ion-exchange chromatography. Several IgE-reactive protein bands have been identified over a wide molecular-weight range. In particular, the 104- and 130-kDa IgE-reactive protein bands were detected. These new bands may correspond to aggregates, as EDTA increased the relative amount of the 60-, 67-, 104-, and 130-kDa IgE-reactive protein bands in Western blot. All these bands were also detected by antiparvalbumin monoclonal antibody, specific to the first calcium-binding site. The longer period of storage increased the relative amounts of the 41-, 80-, 104-, and 130-kDa IgE-reactive protein bands. The 18-kDa band was detected only in fish stored for several days. In conclusion, we have described IgE-reactive protein bands over a wide molecular-weight range (12-130 kDa) in Western blot of cod extract, and shown that EDTA and storage conditions may influence the relative distribution of IgE-reactive protein bands.

Specific humoral immune responses in 12 cases of food sensitization to sesame seed

BACKGROUND

Hypersensitivity to sesame seeds is becoming increasingly frequent, probably owing to the larger use of this compound in international food.

OBJECTIVES

This study investigated serum responses of 12 sesame sensitized patients (seven with food allergy, five with food sensitization), to a sesame protein extract, and attempted at identifying sesame major antigens.

METHODS

Sesame protein extracts were prepared from black, white and brown sesame seeds. Electrophoretic analysis showed similar protein patterns in the three extracts, and proper preservation of the proteins integrity. The brown sesame extract was used to set-up an ELISA assay and measure serum levels of antisesame IgG, IgA, IgM and IgE in 12 samples from sesame-sensitized individuals and six controls. It also allowed to perform western blot analyses in order to investigate the molecular weight of sesame proteins recognized by IgG, IgA and IgE.

RESULTS

Nineteen protein bands were observed upon polyacrylamide gel electrophoresis of the sesame protein extracts. Using this whole extract in ELISA, significant antisesame IgG, IgA and IgE-responses were observed in the serum of sensitized individuals, different from the lower signals obtained with control samples. Western blot analysis demonstrated highly polymorphic IgG and IgA responses and a more restricted IgE response pattern, suggesting that two proteins, respectively, 14 kDa and 25 kDa are mostly involved in sesame IgE-dependent hypersensitivity, the 25 kDa band presenting several characteristics of a major allergen.

CONCLUSIONS

This study reports novel information on the possible involvement of a 25 kDa sesame protein in IgE-dependent hypersensitivity to sesame seeds.

Unusual manifestations of hypersensitivity after a tick bite: report of two cases

BACKGROUND

Ticks are able to transmit, through biting, various viral, parasitic, and bacterial diseases, the best known being Lyme disease due to Borrelia burgdorferi. In addition, ticks may also induce allergic reactions.

OBJECTIVE

A study of immediate and delayed skin reactions are undertaken to give evidence of an IgE-dependent mechanism.

METHODS

Two lumbermen reported having had skin reactions following bites by ticks. Skin prick tests and intradermal tests were performed with what was most probably Ixodes ricinus extract in one case. Specific IgE to whole body extract of wood tick were assayed by radioimmunoassay. Histological and immunohistologic examinations of skin biopsy obtained from a pruriginous skin lesion and from a delayed reaction following the intradermal test, were performed.

RESULTS

One of them had positive immediate reactions to a prick test and an intradermal test with the same extract. Both patients had significant levels of wood tick-specific IgE antibody as well as elevated serum total IgE levels. Histologic examinations of a pruriginous lesion revealed lymphocytic dermal and perivascular infiltration, with evidence of CD8+ T lymphocytes and Langerhans' cells in the perivascular infiltrates. A biopsy of the place of the delayed reaction following the intradermal skin test also showed the presence of dermal and perivascular lymphocytic infiltrates.

CONCLUSION

IgE-dependent allergy to Ixodes ricinus can explain allergic reactions. Standardized extracts have to be prepared with sufficient amounts of the relevant tick salivary antigens to permit diagnosis by skin and serologic tests of patients, especially lumbermen who may be allergic to Ixodes ricinus.

Transfer of atopy following bone marrow transplantation

BACKGROUND

Bone marrow transplantation is an optimal treatment of acute leukemia and aplastic anemia. Allergic manifestations in recipients long after bone marrow transplantation have been reported. A case involving transfer of atopy manifested as food allergy-induced-atopic dermatitis is reported.

METHODS

The donor and the patient were investigated by prick tests and RAST to the same food allergens. Single blind, oral challenge to egg documented food allergy in the recipient.

RESULTS

A 5-year-old boy without history of atopy developed severe atopic dermatitis after bone marrow transplantation from his HLA-identical sister for acute lymphoblastic leukemia. The patient's course had been marked previously by acute graft versus host disease and cytomegalovirus infection. Immunoallergic evaluation showed an exquisite sensitization to egg, peanut, and soybean. Total IgE was 6400 KIU/L. Concomitantly, the donor showed the same sensitizations. Absolute avoidance resulted in the regression of atopic dermatitis. Subsequently, new sensitization to wheat flour, Dermatophagoides pteronyssinus, birch, and plantain pollens was detected. The donor developed asthma.

CONCLUSIONS

This case gives evidence of the transfer of sensitization from donor to recipient. The passive transfer of memory cells within the bone marrow inoculum is a possible mechanism. The current concept of allergy supports down regulation of Th1 cells to the benefit of Th2 cells. Additional deregulation induced by acute graft versus host disease, cytomegalovirus infection, and immunosuppression is possible.

HLA class II antigens and T lymphocytes in human nasal epithelial cells. Modulation of the HLA class II gene transcripts by gamma interferon

BACKGROUND

Nasal polyps are characterized by a proliferation of the epithelial layer of the mucosa, cellular infiltrates and other pathological changes; however the mechanisms involved in polyp pathogenesis remain largely unclear.

OBJECTIVES

We have taken two different approaches to study the cellular events involved in nasal polyposis.

METHODS

First, through use of immunohistochemical methods, we have studied the expression of HLA class II antigens in epithelial cells of nasal polyps and the distribution of lymphocytes in the epithelium and in the subepithelial layer in patients with clinical conditions, such as asthma, atopy, aspirin intolerance or cystic fibrosis, and in subjects with an absence of concomitant diseases. Second, in order to investigate whether HLA class II expression is controlled at the pre- or post-transcriptional level, we studied the effect of interferon gamma (INF gamma) on epithelial cells in primary culture, which were derived from HLA class II negative and HLA class II positive nasal polyps. Total RNA was extracted from the cells and reverse-transcribed, and the c-DNA corresponding to DR, DP, DQ loci was amplified by PCR.

RESULTS

Expression of HLA class II antigens by the epithelia of nasal polyps was more common in the presence rather than in the absence of concomitant asthma, atopy or cystic fibrosis (59% versus 40%). HLA-DR was the only HLA class II antigen expressed in the seven polyps taken from cystic fibrosis patients. The number of CD8+ cells was significantly higher in polyps associated with known clinical conditions and HLA class II antigen expression than it was in 'isolated' polyps and in HLA class II negative polyps. RNA transcripts for at least one or all three HLA-DR, DP and DQ antigens were detected in 10 cultures of the II HLA class II positive polyps. Conversely, 8 of 10 cultures derived from HLA class II negative polyps did not express HLA class II transcripts in the absence of INF gamma. Adding INF gamma (100 U/ml) to the latter cell cultures caused expression of transcripts of one or more HLA class II genes.

CONCLUSIONS

We have shown that HLA class II antigens were more frequently detected in polyps of patients with an identified clinical syndrome than in those of asymptomatic subjects. Our results also suggest that IFN gamma regulates expression of HLA class II antigens in airway epithelial cells of the nasal polyps at the transcriptional level, and that cultured cells from nasal polyps represent a suitable model to investigate immune mechanisms involved in diseases such as atopy, asthma and cystic fibrosis.

Prevalence of lysozyme sensitization in an egg-allergic population

An egg protein, lysozyme, is a still unlabeled additive currently used in cheese preparation. Furthermore, the WHO-FAO committee considers it innocuous. However, 31% of children and 8% of adults with food allergies are allergic to eggs. This work aimed to determine the percentage of patients sensitized to lysozyme from a population of egg-allergic patients. Specific IgE was determined with Cap RAST in 52 patients clinically allergic to egg. Thirty-five percent of egg-allergic patients had antilysozyme IgE. Given this high incidence of lysozyme sensitization, it seems that the presence of lysozyme should be indicated on food labels.

Sesame seed and sesame seed oil contain masked allergens of growing importance

Sesame seed and sesame seed oil have been thought of as rare causes of food allergy, representing less than 1% of all food allergy cases. We now report nine cases of IgE-dependent allergy to sesame seed and/or sesame seed oil, six of which were diagnosed in 1995 alone. Our skin test results draw attention to the poor quality of a commercial sesame seed extract and the good sensitivity of skin prick tests made with a freshly prepared sesame seed flour extract. The diagnosis of this food allergy was established by double-blind oral provocation tests, with doses of sesame seed flour ranging from 100 mg to 10 g. Allergy to sesame seed oil was also demonstrated in some cases. The sensitivity of the Pharmacia Phadebas CAP System for the detection of sesame seed-specific IgE was only mediocre. We draw attention to the important use of sesame seed in modern cooking, a fact which may explain the growing frequency of this allergy. We underline the particular risk with sesame seed oil. Sesame seed should also be considered a cause of allergic reactions to drug products and cosmetics.