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1.
A method allowing the immunopurification of human IgE from small volumes of sera with a yield close to 100% (mean = 97.8%; SEM = 0.7) has been developed. The immunopurification eluates were cleared of other class antibodies that could compete with IgE in specific assays. Immunopurification of IgE followed by specific IgE enzyme-linked immunosorbent assay (ELISA) (IMMEL) was then applied to sera of 160 individuals from an area endemic for Schistosoma mansoni. In comparison with radioimmunosorbent test (RAST) and ELISA performed on unfractionated sera, IMMEL provided the highest specific IgE signals. Furthermore, the best correlations between the specific IgE levels and either the specific basophil histamine release levels (r = 0.84; p less than 10(-4) or the anti-S. mansoni skin test values (r = 0.45; p = 10(-4)) were obtained with IMMEL. Measurement of anti-S. mansoni IgE levels in immunopurified fractions and in unfractionated sera of these 160 individuals revealed a strong serum inhibition (geometric means of 98.6% and 96.8% for the adult worms and the larvae, respectively) of the specific IgE reactivity in ELISA. This inhibition was correlated with the anti-adult worm and anti-larval IgG4 levels (r = 0.65; p less than 10(-4) and r = 0.58; p less than 10(-4), respectively). In contrast, this inhibition did not correlate with the specific IgG1, IgG2, IgG3 and IgM levels. Furthermore, the level of specific IgG4 was clearly lower than that of specific IgG1, suggesting that the major contribution of IgG4 in the competition effect is not due to higher levels but rather to a specificity spectrum close to that of the specific IgE. These results support the idea that a specific function of IgG4 in serum might be to control antigen recognition by IgE and consequently, to regulate anaphylactic reactions and IgE-mediated immunity.  相似文献   

2.
RATIONALE: Although animal models for the study of allergic reactions are desirable, the use of mice has been hindered by the lack of sufficiently sensitive in vitro immunoglobulin epsilon (IgE) antibody assays. The aim of this study was to enhance IgE antibody measurements by immunoglobulin gamma (IgG) depletion. METHODS: Seven- to eight-week-old female mice of four strains (C3H/HeJ, CBA/J, C57Bl/6J, and Balb/c) were immunized (20 mice/group) with shrimp or peanut extracts using Al(OH)(3) as adjuvant. Following immunization, animals were sacrificed by exsanguination and the sera of each group pooled. Initial measurements of IgE antibody levels by enzyme-linked immunosorbent assay (ELISA) were relatively low; IgG and IgE reactivity patterns by immunoblot were similar. Thus, sera from shrimp or peanut immunized mice were depleted of IgG (absorbed 3-6 times with immobilized protein G) and then tested for IgE antibody to shrimp or peanut allergen. RESULTS: A 3- to 5-fold increase in IgE antibody reactivity as measured by ELISA was demonstrated when >80-90% of the IgG was removed. This increase in detection of allergen-specific IgE occurred in sera from all mouse strains and to all allergens tested. In addition, reactivity of IgE antibodies to peanut or shrimp allergens by immunoblot increased visually approximately 4- to 10-fold. CONCLUSIONS: These studies indicate that allergen-specific IgG antibodies, which may be in more than 100-fold excess to IgE antibodies, interferes with detection of allergen-specific IgE, probably by competitive binding to allergenic epitopes. Substantial depletion of IgG antibodies (>80%) result in a significant increase in the sensitivity of the antibody measurements.  相似文献   

3.
Circulating IgG autoantibodies to IgE in atopic syndromes   总被引:4,自引:0,他引:4  
Sera from nonatopic healthy donors and patients with hyper-IgE syndrome, allergic respiratory disease, i.e., allergic rhinitis and asthma, and atopic dermatitis were assayed for the presence of IgG and IgM antibodies to IgE. The assay used was based on an ELISA method that measured the binding of IgG or IgM in test sera to myeloma IgE (PS)-coated microtiter wells. The levels of IgG anti-IgE but not of IgM anti-IgE were elevated in patient sera of all three categories tested. The same sera failed to demonstrate increased levels of IgG anti-IgM or IgG anti-IgA. Significant IgG anti-IgE activity remained after absorption of patient sera over pooled human IgG F(ab')2 Sepharose. The IgG anti-IgE activity appeared to be directed toward the Fc portion of IgE because absorption of positive sera over IgE (ADZ) Sepharose but not over myeloma IgG Sepharose completely removed their reactivity with IgE (PS) and because sera from atopic individuals but not from normal subjects contained IgG anti-IgE activity against the protein backbone of the Fc portion of IgE synthesized from a fragment of the cloned gene of human myeloma IgE (ND) heavy chain. Regression analysis demonstrated a weak but significant correlation (r = 0.31; p less than 0.05) between serum IgE levels and IgG anti-IgE activity. Fractionation of sera from the three patient categories by gel filtration over Sepharose 6B revealed that IgG anti-IgE activity was present both as monomeric IgG and in IgE containing immune complexes (IC). Intermediate molecular size IC (between 7S and 19S) were present in all three patient groups.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

4.
BACKGROUND: Allergens from house dust mites (HDMs), Dermatophagoides pteronyssinus and Blomia tropicalis are clinically relevant in atopic respiratory diseases in tropical countries. AIMS OF THE STUDY: To evaluate immunoglobulin (Ig)E, IgG1, and IgG4 antibody responses to B. tropicalis in Brazilian atopic patients. METHODS: About 110 patients with allergic rhinitis with/without asthma and 33 control subjects underwent skin prick testing (SPT) with HDM extracts, and their sera were tested for IgE and IgG subclass antibodies to D. pteronyssinus and B. tropicalis by enzyme-linked immunosorbent assay (ELISA) and immunoblotting. RESULTS: Most patients (56%) had positive SPT to B. tropicalis extract (B. tropicalis+ group), although 51% were reactive to both B. tropicalis and D. pteronyssinus and 6% were sensitized to B. tropicalis only. IgE-ELISA detected 43%B. tropicalis positivity with high-specific IgE levels in B. tropicalis+ patients. Specific IgG4 levels were higher in B. tropicalis+ than B. tropicalis- groups and correlated with specific IgE levels. The IgG1 levels to B. tropicalis were higher in patients than controls. The major allergenic B. tropicalis components recognized by B. tropicalis+ patient sera were the 54, 66, and 68 kDa proteins. The IgG4-binding protein profiles closely resembled that of IgE. The IgG1 antibodies recognizing multiple B. tropicalis protein species were detected in sera of all three patient groups. CONCLUSIONS: A large percentage of our allergic patients are B. tropicalis+. They are more frequently sensitized to high-molecular weight (HMW) B. tropicalis components than the major low-molecular weight (11-15 kDa) allergens detected in other studies. The results suggest that HMW B. tropicalis antigenic components are potential candidates for evaluating allergen exposure and sensitization, and for immunotherapy treatment.  相似文献   

5.
Blocking phenomenon of the RAST test was studied in the sera of 50 different patients. Specific levels of IgE and IgG against 11 common foods were evaluated by ELISA. Results showed that decreases in IgG levels by protein-A were not always followed by IgE increases. In this regard, we found three different combinations in the levels of IgE and IgG: (1) an IgG decrease followed by IgE increase (29%); (2) an IgG increase followed by IgE decrease (18%); and (3) both IgG and IgE decrease (28%). From these results we concluded that IgG is not the only inhibitor of the RAST test.  相似文献   

6.
In spite of a close genetic relationship among cultivars of wheat ( Triticum aestivum ) and spelt ( T. spelta ) reports of people suffering from avoidance reactions to wheat products often stated a better tolerance of spelt products. The aim of this study was to reveal cultivar specific characteristics in terms of immunologically relevant properties. Pooled sera, containing specific IgE antibodies to cereal flours and pollen, were used to determine the IgE, IgA, IgG1 and IgG4 reactivity directed against water soluble protein fractions from five wheat and spelt cultivars by immunoblotting and ELISA. Analyses were performed with native and denatured protein samples, respectively. Cultivar specific characteristics with respect to binding capacity and polypeptide patterns were found to be most pronounced in IgA and IgE specific assays. Binding capacities of native and denatured cereal proteins differed considerably. IgA, IgE and IgG1 were found to bind higher portions of denatured proteins than IgG4. Microheterogeneity among water soluble proteins of cereal cultivars affects the binding properties of IgA, IgE, IgG1 and IgG4 immunoglobulins. These variations indicate differences in antigenicity and perhaps allergenicity of cereal cultivars.  相似文献   

7.
The immune response to honey bee venom in thirty-seven bee keepers' sera was studied by several methods. Specific IgE antibody levels studied by RAST were generally low, whereas specific IgG antibody levels studied by a Sepharose protein A technique were high. Crossed radioimmunoelectrophoresis was applied for a detailed analysis of the antibody specificities towards the different components of venom in seventeen of the bee keepers' sera. Significant amounts of IgG antibodies were found towards most bee-venom components. The highest IgG response was directed towards phospholipase A. Hyaluronidase, acid phosphatase and two uncharacterized antigens also showed distinct IgG binding. The IgG binding to melittin was low. The IgE binding to the bee venom components was low and primarily directed to the phospholipase. IgE binding to hyaluronidase and acid phosphatase occurred, but was also in very small amounts. One bee-keeper serum caused heavy radiostaining to melittin but the others did not show IgE binding to this component. Thus a low IgE but a high IgG response was demonstrated in bee keepers. The major immunogen was phospholipase A. which is known to be the major allergen in bee venom. Generally, the strongest IgG responses were found to the components capable of inducing the strongest IgE responses.  相似文献   

8.
BACKGROUND: IgE-mediated allergic reactions caused by mosquito bites are a common problem all over the world. This study was undertaken to determine IgE levels in subjects, to elucidate human IgE and mouse IgG1 binding patterns and to investigate the cross-reactivity of salivary gland antigens with three mosquitoes. METHODS: Mosquito larvae of Aedes togoi, Culex tritaeniorhynchus and Culex pipiens pallens were collected and maintained in the laboratory. Salivary gland extracts (SGE) and whole-body extracts (WBE) were prepared from female mosquitoes of each species. Mosquito-specific IgE levels in 17 subjects were measured by ELISA. Polypeptide patterns were analyzed by SDS-PAGE. Immunoblotting was performed with sensitized human and immune mouse sera, and elucidated human IgE and mouse IgG1 binding patterns to SGE. For the determination of cross-reactivity to the three types of mosquitoes, ELISA inhibition tests were performed using sera from mice sensitized by biting of A. togoi. RESULTS: The 9 sera out of 12 with positive skin reactions to SGE of A. togoi by skin prick test showed significantly higher anti-mosquito SGE IgE levels than in those without skin reactions. Protein band patterns of the SGE and WBE of the three species were different from one another. Specific human IgE reacted to the protein in SGE of 30.5, 33, 37 and 57.5 kD from A. togoi, of 38, 43 an 68 kD from C. tritaeniorhynchus, and of 23, 33, 34, 43, 44, 60, 74 and 93 kD from C. pipiens pallens. There were specific mouse IgG1 reactions to the bands of 30.5, 33, 37 and 57.5 kD in the SGE of A. togoi. The ELISA inhibition studies disclosed almost no cross-reactivities between A. togoi, C. tritaeniorhynchus and C. pipiens pallens. CONCLUSIONS: Immunoblot analysis disclosed that allergenic proteins in the SGE of mosquitoes and their patterns were remarkably similar between human and mouse sera to the SGE of A. togoi. Species-shared allergens may not exist among the three mosquito species prevalent in Korea.  相似文献   

9.
Specific allergy vaccination (SAV) is associated with increased levels of allergen specific IgG in serum. It is not clear, however, to what extent qualitative changes in allergen binding to IgG may be induced as well. We therefore analyzed the binding of the major allergen in pollen of birch (Betula verrucosa) (Bet v 1), the major allergen in birch pollen, to serum IgG and IgE, separately and in competition. Sera from six birch pollen-allergic patients were obtained before and after 5 years of SAV, and binding was assessed with 125I-Bet v 1. Before SAV, IgG bound more than eight times the amount of Bet v 1 compared with IgE, and together they accounted for more than 85% of the serum binding capacity. While SAV induced minimal changes in IgE binding, the IgG binding capacities increased 6-32 times. In contrast, the binding avidities (K(d) 28-40pM) changed less than 20%, pre- and post-SAV IgG provided similar inhibition of Bet v 1 binding to IgE at equimolar levels, and cross inhibition studies between IgG and IgE showed low inter-individual differences. Following SAV, all sera reduced Bet v 1 binding to CD23(+) cells, correlating with reduced binding of Bet v 1 to IgE (P<0.001). These results show that high avidity IgG of low inter-individual difference in Bet v 1 binding quality is the dominant binding factor of Bet v 1 in sera of birch pollen-allergic patients, and that SAV-induced inhibition of binding of Bet v 1 to IgE can be explained mainly or solely by increased amounts of IgG.  相似文献   

10.
Sera fromSchistosoma mansoni-infected human patients were tested for total IgE levels and specific IgE and IgG antibodies toS. mansoni adult worm, cercaria, and egg antigen by ELISA. Of 50 sera, 28 were investigated by enzyme-linked crossed immunoelectrophoresis (ELCIE) to detect IgE reactivity to individual adult worm extract components. All sera showed increased total IgE levels. Specific IgE antibody levels to the different antigens varied; they were significantly correlated with each other but independent from total IgE. No correlation was found between specific IgG and any of the IgE antibody levels. Testing of the 28 individual sera by ELCIE revealed heterogeneous patterns. Seven sera were found to be non-reactive: three reacted with one precipitate, and the others reacted with between two and nine precipitates. However, in no case were identical patterns recognized, although four antigens reacted with about 80% of the sera. The number of bands detected by the individual sera depended neither on the levels of total IgE nor on those of specific IgE.Supported by the Bundesministerium für Forschung und Technologie der Bundesrepublik Deutschland (grant PTB 8324)  相似文献   

11.
The aim of this study was to evaluate total IgG, IgG1, IgG4, and IgE antibody responses in human strongyloidiasis by enzyme-linked immunosorbent assay (ELISA) using Strongyloides ratti saline extract as heterologous antigen for a possible clinical utility of the assay. A total of 40 serum samples of patients who were shedding Strongyloides stercoralis larvae in feces (group I), 30 sera from patients with other intestinal parasites (group II), and 30 sera from subjects with negative results in three parasitological assays (group III) were analyzed to detect total IgG, IgG1, IgG4, and IgE to Strongyloides spp. by ELISA and expressed in ELISA index. Levels of total IgG anti-Strongyloides spp. were significantly higher in patients of group I than in groups II (p=0.0005) and III (p<0.0001). Levels of specific IgG1, IgG4, and IgE of group I were also significantly higher than in groups II and III, respectively. There was a significant positive correlation between specific IgE and IgG4 (r=0.6524; p=0.0084) and IgG1 and IgG4 (r=0.5398; p=0.0171). It can be concluded that the detection of specific IgE, IgG1, and IgG4 subclasses rather than total IgG antibodies to Strongyloides spp. using the S. ratti antigen showed to be an additional tool for improving the serodiagnosis of human strongyloidiasis.  相似文献   

12.
Sera of patients with ABPA were tested by XRIE tests incorporating their own serum (self-XRIE) to detect the presence of IgG/IgE antigen complexes to a “reference” Aspergillus fumigatus preparation. Of the 32 sera studied, 29 (90%) had visible precipitin (IgG) peaks, and 27 of these 29 as well as the three apparently precipitin-negative sera, i.e., 30 (94%), showed binding of specific IgE by autoradiography. The two precipitin-positive sera that did not show IgE binding were also skin test negative and RAST negative to this A. fumigatus antigen. Specific IgG as determined in ELISA correlated well with the grading of the XIE precipitin peaks (p < 0.05). There was also a highly significant correlation between specific IgE by RAST and grading the radioactive uptake seen in the autoradiograph (p < 0.001) indicating, for each serum, the presence of IgG antibodies to most of the components to which there was specific IgE. In the self-XRIE tests there was considerable variation of reactivity from serum to serum, in numbers of antigen/antibody peaks observed, in relative peak heights, and in the intensity of the respective staining. By comparing each test to a “reference” pattern developed with the use of an ABPA serum pool, the antigenic components of A. fumigatus were found to be of two main types: (1) antigens that appeared to be poorly precipitating (possibly low-molecular-weight components) but showed strong IgE binding (these were apparently major allergenic components and with one exception proved to be the faster migrating components) and (2) antigens that produced the strongest precipitin reactions with only weak binding of specific IgE and therefore minor allergenic components.  相似文献   

13.
Ten children, aged 3 to 12 years old (mean 8), with house-dust-mite sensitive bronchial asthma were hospitalized and administered a course of rapid injection immunotherapy with house-dust (HD) antigen. In order to evaluate rapid injection immunotherapy, we examined total IgE, anti-HD IgE and IgG4 antibodies, anti-mite (Dermatophagoides farinae: DF) IgE antibodies, and anti-DF IgG4 antibodies in their sera serially from 56 to 80 weeks after rapid injection. The results were as follows: 1) All of their clinical courses were markedly improved by this immunotherapy. 2) Total IgE levels were unchanged. 3) Anti-HD IgE antibodies were decreased 5 weeks after rapid administration (p less than 0.01). And anti-DF IgE antibodies were also decreased (p less than 0.05). 4) Anti-DF IgG4 antibodies were increased more than twofold from 2 to 5 weeks after rapid administration (p less than 0.02). Rapid injection immunotherapy produced positive effects in some of the asthmatic children. This seemed to be attributable to the production of antigen specific IgG4 antibodies (said to be blocking antibodies) and the reduction of antigen specific IgE antibodies.  相似文献   

14.
The significance of food specific serum IgG4 antibody in food allergy is unclear and this led us to investigate the relevance of specific IgG4, along with IgG and IgE antibodies to two common food allergens in Malaysia. Enzyme-linked immunosorbent assay (ELISA) was used to measure the serum antibodies in 143 allergic rhinitis patients' sera, of which 47 were from patients with clinical indication of shrimp allergy, 46 with clinical indication of crab allergy and 50 without indication to either allergy. Clinical indication of allergy was based on answers to a questionnaire or results of the skin prick test. We found that the elevation of specific IgE or IgG4 is associated with shrimp and crab allergies but elevation of specific IgG is not associated with either allergy. However, the clinical utility of elevated specific IgG and IgG4 levels is pending further investigation.  相似文献   

15.
Antigenicity and specificity of two major allergens termed J1 and J2, both of which had been purified from soluble egg antigen (SEA) preparation of Schistosoma japonicum, were examined against serum from schistosomiasis japonica patients. By using enzyme-linked immunosorbent assay, specific IgE or IgG levels to J1 or J2 in the patients' sera correlated well with those to crude SEA, indicating that J1 and J2 are the major antigens in SEA binding human IgE and IgG antibodies. Binding inhibition studies using 125I-J1 and 125I-J2 clearly showed that cross-reactivity was not present between J1 and J2 in terms of their capacity to bind IgG or IgE antibody. When antibody levels of an individual patient to these two purified antigens were compared, a high degree of correlation was observed between them, regardless of the class of antibody. However, specific IgE antibody levels of individual serum to J1 or J2 were not correlated with IgG antibody levels to the respective antigen.  相似文献   

16.
Venom-specific IgE and IgG antibodies were measured in the sera of bee-venom-sensitive patients during a 3-year hyposensitization period. The level of specific IgG antibodies initially increased, and 2 months after the start of therapy, this increase was on average five-fold. A concomitant hut non-significant increase in specific IgE antibodies was also observed initially. Later during the treatment period specific IgE antibodies showed a continuous decline and after 3 years the level was one third of the pre-treatment level. Venom-specific IgG antibodies, however, remained above the pre-treatment level. The disappearance of the severe allergic reactions was related to the level of both IgE and IgG antibodies as demonstrated in seventy-six bee sting challenges. In patients with specific IgG antibody levels above 400 u/ml, no severe reactions were observed even if the patient had levels of specific IgE- antibodies of RAST class 3 or 4. These data suggest that the relationship between venom-specific IgE and IgG antibodies permits an evaluation of the state of immunity to insect stings.  相似文献   

17.
B-cell epitopes of bovine αS1-casein, one of the major allergens of cow's milk, were identified by a screening method based on synthetic peptides. According to the known amino acid sequence of αS1-casein, a set of 188 overlapping sequential decapeptides shifted by one amino acid was manually synthesized on polyethylene pins by the 9-fluorenyl-methoxycarbonyl (Fmoc) method. Peptides were screened by an enzyme-linked immunosorbent assay (ELISA) specific for human IgE and IgG. Bound antibodies were detected by successive incubation with up to three polyclonal antibodies, the last one conjugated to horseradish peroxidase. Tested sera were from 15 patients with acute clinical reactions to cow's milk and IgE-specific reactions to bovine α-casein in the ELISA and immunoblot. Sera from 10 healthy subjects without remarkable reactions to cow's milk proteins were used as controls. All sera from allergic subjects showed reactions with three regions of αS1-casein, corresponding to amino acids 19–30, 93–98, and 141–150. Furthermore, individual sera showed reactions with other parts of the protein. No essential differences in the epitope specificity of IgE and IgG were found. Inhibition of IgE binding to αS1-casein with soluble synthetic peptides confirmed the results and revealed peptide CN-2 as the most inhibiting one.  相似文献   

18.
The IgG and IgA subclass distribution of specific antibodies as well as the distribution of total and specific IgE in 15 patients with schistosomiasis was determined in consecutive samples before and after initiation of treatment. An adult worm antigen preparation and a soluble egg antigen preparation were used as antigens in the ELISA assays. After initiation of treatment a rise was noted in certain subclasses and a correlation was found for specific IgG1 and IgG4 serum levels in the egg-excreting patients against adult worm antigen and for specific IgG4 and IgE levels in sera from the eight patients with a chronic disease. They also had a rise of the specific IgA1 titre and six of them also of specific IgA2. Members of eosinophilic granulocytes reached a peak after 2 weeks in seven of the eight patients. The increase of eosinophils was an early event as opposed to the incidence of peak of the determined specific isotypes. The associated rise in IgG1, IgG4 and IgE antibody concentrations and eosinophils may suggest a causal relation possibly induced by common interleukins.  相似文献   

19.
Mite antigens (Dermatophagoides farinae) were fractionated by a Sephadex G-200 column and their reactivities with IgE, IgG1 and IgG4 antibodies were investigated with enzyme-linked immunosorbent assay (ELISA). High IgE antibody values were observed in fractions with low molecular weight (allergenic part), while high IgG1 and IgG4 antibody values were observed in fractions with high molecular weight. High IgG4 antibody values to crude mite extract and fractions with high molecular weight were detected in individuals who had received immunotherapy. However, IgG4 antibodies directed to allergenic part were found in only one out of 12 sera tested. IgG4-ELISA using DF1 (major allergen of Dermatophagoides farinae) as antigen was also performed. In the group treated with mite, significant IgG4 antibody levels were detected in only one out of 13 sera tested. In the group treated with house dust, significant IgG4 antibodies were detected in only one out of 12 sera tested. Patients who showed high IgG4 antibody responses to crude mite extract and to high molecular weight did not show responses to allergenic part and DF1. The only case who showed positive IgG4 responses to allergenic part also reacted with DF1. Those results suggest that IgG1 and IgG4 antibody values in ELISA using crude mite extract as antigen do not reflect major allergen-specific antibody values. The importance of the use of partially purified antigens in measuring major allergen-specific IgG4 antibodies was also suggested.  相似文献   

20.
IgE and IgG antibodies against Aspergillus fumigatus were detected by crossed radio immunoelectrophoresis (CRIE) on the sera of seven patients with aspergilloma, six patients with allergic broncho-pulmonary aspergillosis (ABPA) and 25 patients with extrinsic asthma with Aspergillus allergy. IgE-CRIE analysis indicated the presence of A. fumigatus-specific IgE in sera of patients with ABPA and Aspergillus asthma but not of aspergilloma patients. IgG-CRIE showed that both aspergilloma and ABPA patient sera contained high levels of circulating specific IgG antibodies in contrast to sera of Aspergillus asthma patients, which did not show detectable amounts of Aspergillus-specific IgG antibodies. Specific IgE binding could be demonstrated for the major allergens Ag-10 and AG-40 in all ABPA patients, in 80% of Aspergillus asthma patients but not in sera from aspergilloma patients. Specific IgG antibodies directed towards the major allergens could be detected in most of the aspergilloma patients, between 30-70% of the ABPA patients but not in sera from patients with Aspergillus asthma.  相似文献   

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