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Background: The authors clarified the clinical significance of the measurement of serum concentrations of specific IgE antibodies to staphylococcal enterotoxin (SE) A- and SEB in atopic dermatitis (AD). Methods: The serum concentrations of SEA- and SEB-specific IgE antibodies in 140 pediatric patients with AD were measured with an immuno CAP −radioallergosorbent test system (RAST). To check the cross-reaction of specific IgE antibodies to SEA/SEB and other allergens, the CAP RAST fluorescent enzyme immunoassay inhibition test was performed. Results: Forty-seven patients (33.6%) tested positive for either SEA- or SEB-specific IgE antibodies. School children showed higher positive rates of SEA/SEB-specific IgE antibodies than infants or young children. The patients with severe AD and those with exacerbation of symptoms in summer, had higher positive rates of SEA/SEB-specific IgE antibodies than patients with mild AD or those with exacerbation in winter. In addition, the positive rates of specific IgE antibodies to both dog-dander and cat-dander were higher in patients with positive SEA/SEB-specific IgE antibodies than in patients with negative ones. No cross-reactions occurred among specific IgE antibodies to SEA/SEB and dog/cat dander with one patient's serum, which had positive IgE-specific antibodies against cat/dog dander and SEA/SEB. The positive rate of SEA/SEB-specific IgE antibodies in the patients with dogs and/or cats as pets was 48.4%, which was higher than in those with no pets. Conclusions: Atopic dermatitis patients who exhibit high positive rates of SEA/SEB-specific IgE antibodies were found to be school children, severe cases, cases with high serum concentrations of total IgE, cases with exacerbation in summer, and cases with dogs and/or cats as pets. The measurement of serum concentrations of specific IgE antibodies to SEA and SEB, thus has some value for evaluating AD patients.

Background The antigen-specific interleukin-2 response (AIR) test using lymphocytes is effective in searching for the antigen which causes allergic diseases and understanding their disease activity . Objective and Methods The correlation between the raw egg oral provocation test and egg white antigen-specific interleukin-2 (IL-2) response test was investigated in 123 children with infantile atopic dermatitis and 13 children with bronchial asthma. Results Among the 83 who showed positive reactions to provocation, 75 also reacted positively to the AIR test (sensitivity, 90.4%), while among the 53 children who showed negative responses to antigen provocation, 45 produced negative responses to the AIR test (specificity, 84.9%). The specificity of egg white IgE RAST score and skin-prick test are 88.7 and 81.3% which are comparable to that of the AIR test. However, their sensitivity was low (38.6 and 66.7%). In the patterns of symptom developed in the provocation AIR displayed late and delayed type allergic responses in addition to the immediate type which RAST reflected. The RAST-negative group composed of 98 patients included 51 (52.0%) who exhibited positive reactions to the provocation test. Among these 44 responded positively to the AIR test (86.3%). Conclusion The AIR test is effective for screening egg white antigen as part of the tests for antigens responsible for allergic diseases and as a test to ascertain the relevant antigens, and that the conditions that could not be diagnosed by RAST can be detected by the AIR test.

A dried food (juice) containing freeze-dried egg white and a placebo were obtained. The usefulness of the dried food in pediatric allergy practice was evaluated in 50 infants and children who had eliminated consumption of eggs and egg products due to confirmed or suspected egg allergy. The purpose of the challenge test with the dried food was to assess the degree of immediate-type hypersensitivity and/or tolerance to egg.This test was carried out using the single open food challenge method. Because the amount of the dried food administered as the test dose depends on the degree of hypersensitivity, 1 to 10mg of dried food (0.38-3.8mg freeze dried egg white) was set as the initial dose. If no reaction occurred within 30 minutes, the dose was increased 5-fold to 10-fold in subsequent tests until 7, 700mg was reached. No reaction at 7, 700mg was defined as negative test to egg. Results were as follows.1. Immediate-type reaction was found in 25 patients, and the amount of dried food administered by onset of apparent immediate reaction ranged from 10 to 7, 700mg.2. Non-immediate type of reaction was revealed respectively in 2 and 3 cases, and biphasic reaction of immediate and late types was observed in 2 patients.3. Negative test to egg was observed in 18 patients.4. No patient experienced esystemic anaphylactic reaction due to those challenge test.5. Placebo-food was adopted, when in presumption of uncertain result, and was used in 23 for single blind and in 13 cases for double blind placebo-controlled food challenge tests.Though there were some aspects of this procedure of this test with dried food containing freeze dried egg white that should be improved, it was thought that when by the above-mentioned method, this food was adapted for clinical evaluation of hypersensitivity to egg, particularly for purposes of assessing the degree of hyper-sensitivity and/or tolerance to egg.

Children with asthma usually become asymptomatic by the time they reach age 20 y. To clarify the immunologic mechanisms responsible for this phenomenon, we studied patients in remission and others who still had frequent asthma attacks. Patients were grouped by clinical status, and three variables were measured: serum levels of IgE, production of IL4 and interferon (IFN)-gamma, and the activation of T cells induced by Dermatophagoides farinae (Df) antigen. Df-induced activation of T cells (as measured by antigen-induced IL2 responsiveness) or IL2 synthesis itself was induced in patients with active asthma but not in normal subjects. These responses were much weaker in patients in remission. When stimulated by Df antigen in vitro, lymphocytes from patients with active asthma produced much more IL4 than did the cells from normal subjects, and cells from patients in remission produced only a small amount. In contrast, under similar conditions lymphocytes from patients with active asthma produced less IFN-gamma than did the cells from normal subjects. Production of IFN-gamma stimulated by Df antigen was high in patients in remission but not in normal subjects. Thus, upregulated IFN-gamma production after exposure to Df antigen might reduce IL4 secretion, which would suppress IgE production and would improve clinical status. Df antigen may suppress Df-induced allergic responses in patients with asthma in remission.

Cells producing IgA specific to ovalbumin (OVA) were detected with an assay of plaque-forming cells (PFC). Non-T cells were separated on a polystyrene resin column and were further depleted of B cells that bound sheep erythrocytes (SRBC) by SRBC-rosette sedimentation. The cells were recombined with T cells separated on a polystyrene resin column, stimulated with OVA antigen, and then cultured for 5 d. The number of OVA-specific IgA-PFC from the lymphocytes of infants allergic to hen's eggs (7 +/- 5 per 7 x 10(4) non-T cells, n = 9) was significantly less than that of PFC from lymphocytes of age-matched controls (110 +/- 18 per 7 x 10(4) non-T cells, n = 7) and from those of children with atopic dermatitis who were not allergic to hen's eggs (90 +/- 30 per 7 x 10(4) non-T cells, n = 4). Patients' B cells added to the culture supernatant from OVA-stimulated normal T cells (82 +/- 18 per 7 x 10(4) non-T cells, n = 4) were able to produce the specific IgA to levels comparable to those of normal B cells (92 +/- 9 per 7 x 10(4) non-T cells, n = 6), but the patients' T cells did not cause normal B cells to produce the antibody (8 +/- 2 per 7 x 10(4) non-T cells, n = 4). This indicates that the patients' T cells were less able than were normal T cells to promote the production of OVA-specific IgA-PFC. Until the age of 6 y, the ability of the patients' lymphocytes to produce specific IgA was abnormally low; from that age on, it was normal. At the stage of allergen entry, this transiently low production of OVA-specific IgA may contribute to the onset of allergy to hen's eggs.

Peripheral blood eosinophils, nasal eosinophils, serum immunoglobulin G,A,M,E, allergic skin tests, RAST tests, viral antibody and secretory IgA levels were studied in one hundred asthmatic children who had had their first asthma attack before 24 months of age. Viral and bacterial infections were detected in 26 of 79 episodes of attacks. Parainfluenza was most frequently associated, and next in frequency were respiratory syncycial virus, mycoplasma pneumoniae and measles. The serum IgE and IgM level was higher than the normal range for age. In 16.9% serum IgA showed a lower level than in normal children. The allergic skin test by scratch method was positive in 47.6% to egg white, 39.7% to house dust, 44.1% to Dermatophagoides farinae. The RAST test showed similar results. Secretory IgA in saliva was examined by the method of enzyme linked immunoassay. Secretory IgA in infants with egg allergy was lower than in normal healthy children. The predisposition to the development of atopic disease with, maturationally related decreases in secretory IgA could be explained by the ingress of allergic materials.