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1.
Patients allergic to ragweed pollen who did not receive immunotherapy had an increase in ragweed-specific IgE antibodies associated with seasonal exposure. Of 17 such patients, 15 reached peak levels between mid-September and mid-October. Two had peak values after mid-October; the levels were only slightly higher than earlier values. Our study shows that serum obtained in mid-October reflects approximately the maximal IgE antibody level attained 0y ragweed-sensitive patients in our area and that this value can be used as a baseline in monitoring the subsequent decline in antibodies. In addition, our data support an earlier observation that the magnitude of seasonal rise in IgE antibody is related to the preseasonal value. The significantly positive correlation of the results of carefully performed skin tests (end point titration) with radioallergosorbent test (RAST) values suggests the possibility that the RAST can be employed as a reliable diagnostic aid, perhaps even replacing the skin test.  相似文献   

2.
Because of conflicting reports in the literature concerning the value of various procedures for measurement of IgE in serum and secretions, we compared four different methods, the radioimmunosorbent test (RIST), the double-antibody radioimmunoassay (RIA), the paper disc immunosorbent test (PRIST), and radial immunodiffusion (RID). The standards used in the assays were tested initially in the double-antibody RIA with the use of the reference from the World Health Organization. The results showed that RID as expected was relatively insensitive and IgE was reliably measured only above approximately 1,000 international units (IU). Moreover, certain sera containing low levels of IgE by the other procedures gave distinct precipitin zones and presumably falsely high levels of IgE protein. Thus RID may yield apparently erroneous results when used as a screening procedure for measurement of IgE levels. Among the other procedures PRIST and the double-antibody RIA showed the best agreement. With serum samples RIST yielded values for IgE in the low level range higher than those given by the PRIST and double-antibody RIA. With breast milk and colostrum, values of IgE between 120 and 690 ng/ml were found by RIST, whereas IgE was not detected by double-antibody RIA and PRIST. No evidence of an inhibitor of IgE was found in breast milk, so that the apparent elevation of IgE in breast milk by the RIST is likely false. These findings confirm prior reports of spurious elevations of IgE with the RIST and indicate the usefulness of the PRIST and double-antibody RIA for the measurement of IgE in sera and secretions.  相似文献   

3.
IgE antibodies have been measured by the radioallergosorbent test (RAST) and the relative amounts present in serum determined by comparison with reference standards. In this study we analyzed the quantitative aspects of the binding of IgE antibody to solid-phase ragweed antigens. With the volumes of allergic serum usually tested, IgE antibodies are in excess in the first step of the RAST. The inability of solid-phase antigens to remove IgE antibody appeared to be due to an insufficient quantity of antigen on the particles rather than steric interference with binding of IgE antibody. Dose-response curves with serums from several ragweed-sensitive subjects were not parallel when plotted on a semilog scale. In contrast, log-log plots of dose-response curves with serums from ragweed-sensitive subjects were nearly parallel. Log-log plots of dose-response curves with serums from subjects with ragweed and grass sensitivity and tested with the appropriate solid-phase antigen also were nearly parallel. Because of the latter finding, RAST could be standardized using a reference serum in every assay and plotting the results on a log-log scale. Finally, because IgE antibody is in excess in the RAST as it is usually performed, the final result reflects both the quantity and the affinity of the IgE antibody.  相似文献   

4.
Since its introduction by Wide, Bennich, and Johansson in 1967, the radioallergosorbent test (RAST) has been increasingly used for measurement of specific IgE antibodies. In this study we have varied the conditions during the performance of the RAST and have investigated the effect of altering: (1) the speed of rotation of tubes, (2) the number of washes in both steps of the test, (3) the length of rotation of tubes, (4) the temperature, (5) the conditions during centrifugation, (6) the quantity of antibody to IgE in the second step of the test, (7) the composition of buffers in the reactions, (8) the type of tube employed in the test, (9) the quantity of antigen employed during the coupling procedure, and, finally, (10) the iodine isotope, 125I or 131I, used to radiolabel anti-IgE. Of these variables the most significant were the quantity of anti-IgE used in the second step of the test and the quantity of antigen used in the coupling procedure. Other variables of importance were the choice of radioiodine, whether the tubes were rotated or not, the type of tube used, and finally the diluent employed.  相似文献   

5.
Whole ragweed plants were collected before and during the ragweed pollination season and extracts of various portions of the plants were analyzed for antigen E (AgE) and for their inhibitory potency in the radioallergosorbent test (RAST). Ragweed stems and roots contained very low, if any, AgE. AgE was present in very small amounts in anthers prior to pollination season, increased with anther and pollen grain maturation, peaked with the appearance of significant airborne pollen grains in mid-August, and fell slowly through late September. Leaf AgE content also rose during mid- and late August, but brief rinsing reduced antigen E content by almost 50%. Significant RAST inhibitory activity was found only in anthers and the activity paralleled the content of AgE.  相似文献   

6.
7.
The effect of immunotherapy with aqueous ragweed pollen extract on changes in IgE antibody was analyzed in 40 untreated patients with ragweed hay fever and compared to changes in 63 treated patients. Treated patients received cumulative doses prior to and during treatment ranging from 1.4 × 105 to 4.8 × 106 protein nitrogen units (PNU). IgG antibody to ragweed antigen E (AgE) was measured by radioimmunoprecipitation, while IgE antibody to allergens in crude ragweed extract was measured by the radioallergosorbent test (RAST). The RAST procedure was calibrated using a serum whose content of IgE antibody in nanograms per milliliter had been determined by immunoabsorption, and with this method the absolute quantities of IgE antibodies to ragweed allergens could be measured. Control experiments indicated that the IgG antibodies in the sera of the treated patients did not interfere with the measurements of IgE antibodies. The levels of IgE antibody in serum varied from less than 5 ng/ml to approximately 3,000 ng/ml. IgE antibodies decreased from October, 1973, to July, 1974, and rose sharply from July to October, 1974, following the pollination season. In both untreated and treated patient groups the magnitudes of the decreases were related (p < 0.001) to the levels of IgE antibody in October, and the magnitudes of the rises were related to the levels of IgE antibody in July. In the treated patients with IgE antibody less than 71 ng/ml in October, the rate of decrease (October to July) was less than in the untreated patients. Comparison of the rises in IgE antibody from July to October revealed that these were partially suppressed in the treated group (p < 0.001), and this effect was most marked in patients with July levels less than 36 ng/ml. Levels of IgG antibody to AgE in the treated patients were approximately 70-fold greater than in untreated patients and showed little change over the study period. The levels of IgG and IgE antibody in the treated patients were positively correlated (p < 0.001) at all time periods, and patients with high levels of IgG antibody also had greater declines and rises in IgE antibodies. The results indicate that immunotherapy is associated with (1) a reduction in the seasonal decrease in IgE antibody from October to July in patients with the low levels of IgE antibody, (2) a partial suppression of the rises in IgE antibody from July to October, and (3) that both these effects are related to the level of IgE antibody before the change. In many treated patients both IgE and IgG antibodies were low in spite of parenteral administration of ragweed extract. This result is consistent with the view that overall humoral immunologic reactivity to ragweed antigens is reduced in these patients.  相似文献   

8.
Intranasal administration of a 4% solution of cromolyn sodium for the treatment of ragweed hay fever was tested in an 8-week double-blind matched-pair study involving 66 patients. Patients on active drug received 5.2 mg into each nostril 6 times daily; control patients received a placebo spray. The treated group showed a significant reduction in mouth breathing (p less than 0.001), stuffy nose (p less than 0.002), runny nose (p less than 0.003), and postnasal drip (p less than 0.035). Patients receiving the active drug also reported fewer sneezing episodes (p less than 0.003) and nose blowing episodes (p less than 0.015). One patient using cromolyn solution developed nasal ulceration, tongue swelling, coughing, and wheezing. Other side effects were minimal and occurred with equal frequency in both groups. In the treated group relief of symptoms was most marked in patients with high preseasonal levels of IgE ragweed antibody. Intranasal 4% cromolyn solution appears to be an effective drug for the treatment of ragweed hay fever; measurement of the preseasonal level of IgE ragweed antibody is a useful screening test to identify patients most likely to achieve a maximal beneficial response to treatment.  相似文献   

9.
The potencies of 11 commercial extracts of short ragweed pollen were analyzed by skin test end point titration and compared to potency as measured in vitro: (1) by the radioallergosorbent test (RAST), (2) by AgE concentrations, and (3) by protein nitrogen determinations (PNU). RAST potency was determined by the capacity of the extract to inhibit the binding of IgE antibody to solid-phase allergen in the first step of the RAST, and it was expressed as the quantity of extract needed for 50 per cent inhibition of binding. Potencies determined by skin testing in 7 patients were strongly related among the various patients in spite of a 1,000-fold difference in the patients' sensitivity to the extracts. Similarly, potency as measured by RAST inhibition showed about a 1,000-fold difference among the extracts, and the RAST potencies were strongly related to potency as measured by skin testing. Purified antigens derived from short ragweed inhibited binding of IgE antibodies, but the slopes of the inhibition curves were significantly less than those produced by crude or partially purified short ragweed. AgE concentration and PNU concentrations also were correlated with skin test potency, but the range of potencies was less than that found by RAST inhibition. Measurement of the potency of extracts by RAST inhibition should prove useful as a general procedure for the standardization of allergy extracts.  相似文献   

10.
The ability to covalently couple Alternaria allergens to macrocrystalline cellulose particles has permitted not only the measurement of IgE antibodies to Alternaria in patient serums but also the identification of allergenic fractions from crude Alternaria extracts. Crude aqueous Alternaria extracts from 3 commerical suppliers were coupled to cellulose but failed to bind more than 5% of total radioactive counts (TRC) when reacted with serums from highly sensitive patients. Fractionation of a commercial extract through Sephadex G-25 showed that almost all allergenic activity was located in a protein and carbohydrate-containing peak eluting at the column void volume. These fractions were pooled and coupled to cellulose to yield a RAST polymer which produced up to 20% TRC binding when tested with serums from over 100 Alternariasensitive patients, and only up to 1% TRC binding with 17 nonallergic serums. The study of commercial Alternaria extracts by chromatographic and RAST inhibition techniques showed that present extracts are neither qualitatively or quantitatively comparable.  相似文献   

11.
The relative potency of 12 commercial Alternaria extracts was analyzed by end-point skin test titrations and compared to in vitro measurements of potency, including (1) the radioallergosorbent test (RAST) inhibition procedure; (2) the direct RAST procedure; and (3) the protein nitrogen unit (PNU) content. Potencies determined by skin testing 10 sensitive patients were strongly correlated among the various patients. Measurements of potency by both RAST inhibition and direct RAST assay were strongly correlated to potency as measured by skin testing. In contrast, neither the weight:volume nor the PNU content bore any relationship to allergenic potency as measured by skin testing or by either of the RAST procedures. Extracts differed by as much as 3,000-fold in allergen content by skin testing. Moreover, the extracts appeared to contain different allergenic determinants when tested by RAST inhibition. RAST inhibition offered several technical advantages over the direct RAST procedure, in that only one solid-phase RAST reagent was required, slopes of dose-response curves could be more easily compared, and a greater discrimination in allergenic potencies among extracts could be made. The RAST appears to offer an excellent method for measuring the potency of allergy extracts, pending the isolation and characterization of actual allergens.  相似文献   

12.
The effect of treating ragweed pollinosis with intranasal cromolyn sodium powder was evaluated in 26 patients in a double-blind clinical study. Thirteen matched patient pairs were treated by either nasal insufflation of cromolyn sodium powder, 20 mg three times daily, or by a placebo powder. Patients were monitored for severity of symptoms by means of daily symptom diaries collected weekly throughout the pollen season. Serum samples were obtained in July prior to the ragweed season and following the ragweed season during the first and fourth weeks of October for the determination of ragweed-specific IgE antibody levels by the radioallergosorbent test. A significant reduction in symptom severity was observed in the treated patients with high preseasonal levels of IgE antibody to ragweed. Initially the levels of IgE antibody to ragweed did not differ between the two groups. IgE antibody levels increased in both groups after pollen exposure, but the treated group showed a significantly greater rise in IgE antibody levels. The results suggest that treatment with cromolyn sodium enhanced IgE antibody response to pollen exposure and significantly reduced the severity of hay fever symptoms in patients with high preseasonal levels of IgE antibody to ragweed.  相似文献   

13.
The diagnosis of food allergy is often difficult to make by conventional means. Histories are frequently ambiguous, and skin testing is of dubious reliability because of the number of false-positive and false-negative reactions. We have evaluated the radioallergosorbent test (RAST) for the in vitro measurement of the specific IgE antibodies to nuts, including Brazil nut, almond, walnut, pecan, cashew, and the legume, peanut. Serums were obtained from 18 patients with a history of nut allergy and IgE level and specific IgE antibodies were measured. Thirteen of the 18 patients had significantly elevated IgE antibody (greater than twice control) to one or more of the allergens. Prausnitz-Küstner tests on selected serums in general corroborated the results of the in vitro studies. Five patients had RAST elevations to 2 or more nuts. As a group RAST-positive patients had elevated mean serum IgE levels and more severe clinical symptoms (p less than 0.01). The specificity and cross-reactivity of IgE antibodies to different nut antigens was investigated by RAST inhibition with serums from 5 patients having high levels of IgE antibody. In 4 patients no cross-reactivity between Brazil nut and peanut was found. In contrast, several nut extracts inhibited the reaction of pecan allergen with IgE antibodies. These results indicate that specific IgE antibodies can be measured by RAST in patients with nut allergy and the cross-reactivity of nut antigens can be investigated. RAST would appear to be most useful in confirming the diagnosis of nut hypersensitivity in children or in highly allergic patients in whom skin testing poses a risk of anaphylaxis.  相似文献   

14.
We studied topical ocular administration of a 4% solution of cromolyn sodium (CS)for treatment of 112 patients with ragweed conjunctivitis in two 8-wk, double-blind, matched-pair studies. During the 1977 and 1978 ragweed seasons, patients instilled a daily total of 12.8 or 19.2 mg CS into each eye, control patients received placebo drops. Treatment efficacy was assessed by daily symptom score diaries, ophthalmic examinations, and a subjective report by the patient at the end of the trials. In the 1977 trial, CS pair members whose preseasonal immunoglobulin E antibody level was <99 ng/ml showed a significant reduction in eye itching (p < 0.01), eye irritation (p < 0.02), visual blurring (p < 0.025), and nasal congestion (p < 0.025) and required less supplemental medication (p < 0.02) during the peak pollen period. In the 1978 trial all patients had IgE antibody levels >100 ng/ml. CS pair members showed a significant reduction in rhinorrhea (p < 0.004) and nasal congestion (p < 0.007) only; no significant reduction in eye symptoms was noted. Transient eye burning was noted by a total of 38 CS and 39 placebo patients from both studies; ophthalmic examinations were unremarkable; and no other side effects were noted. The 4% CS ophthalmic solution provided significant relief of nasal symptoms in both the 1977 and 1978 trials, but significant relief of ocular symptoms was noted only in the 1977 trial and only in those patients with lower preseasonal IgE ragweed antibody levels.  相似文献   

15.
The presence of serum IgE antibodies to melittin was tested by the radioallergosorbent test (RAST). Melittin, the principal protein of honeybee venom, was isolated by gel filtration on Sephadex G-75 and covalently bound to cyanogen bromide-activated microcrystalline cellulose. The melittin preparation was homogenous by immunoelectrophoresis with the use of rabbit antiserum to whole honeybee venom and by polyacrylamide electrophoresis in gels containing 1% sodium dodecyl sulfate. Elevated serum IgE antibodies to melittin (three times greater than binding by normal sera) were found in 7 of 24 honeybee venom-sensitive persons and in 5 of 20 nonsensitive beekeepers. In one venom-sensitive patient a particularly high titer of IgE antibody was found. The reaction between solid-phase melittin and IgE antibody could be inhibited by fluid-phase melittin but not by phospholipase A (PLA). Similarly, the reaction of IgE antibody with solid-phase PLA was inhibited by PLA but not by melittin. In passive transfer skin tests with the sensitive patient's serum, positive wheal-and-flare reactions were obtained in 3 nonallergic recipients following melittin challenge; appropriate controls were negative. These results indicate that melittin is an allergen in some honeybee venom-sensitive patients and in an occasional patient melittin may be a major allergen.  相似文献   

16.
Lodoxamide ethyl is a new cromolyn-like drug which prevents antigen-induced mediator release from mast cells and antigen-induced bronchoconstriction in sensitive animals and man. The purpose of this study was to determine the effect of a single administration of lodoxamide ethyl on allergy skin tests. The effect of this drug on allergy skin testing was studied in a double-blind design on ten adult subjects allergic to ragweed. Serial end-point titrations with short ragweed extract and with histamine were performed after a placebo and 1- and 3-mg capsules of lodoxamide ethyl. The immediate wheal-and-flare responses as well as the late allergic reaction were recorded. No statistically significant difference was found between lodoxamide ethyl and placebo in the suppression of the allergen-induced immediate wheal-and-flare response or the late allergic reaction. Furthermore, 1 and 3 mg of oral lodoxamide ethyl did not inhibit the histamine-induced cutaneous reactions.  相似文献   

17.
To determine the immunological and biochemical consequences of chronic honeybee venom administration to humans, we studied beekeepers and their family members in two separate investigations. In the first of these studies serums were analyzed for their content of antibodies to honeybee constituents. IgE antibody levels to honeybee venom (HBV), venom sac (HBVS), and phospholipase-A (PLA) were significantly elevated in beekeepers and their family members as compared to non-beekeeper controls. However, IgE antibody levels to HBVS, HBV, and PLA did not distinguish sting-sensitive from non-sensitive beekeepers. IgE antibody levels to honeybee whole body (HBWB) were highest in beekeepers with histories suggestive of inhalant sensitivity to bee body dust. IgG antibody levels to PLA were highest in non-sensitive beekeepers stung daily or weekly; there was a significant positive correlation between IgE and IgG antibody levels to PLA in these beekeepers. In the second study the potentially harmful effects of chronic venom administration were sought, especially evidence of chronic renal disease. While a number of beekeepers and family members showed minor abnormalities in their urinalysis or blood chemistry determinations, in most instances the incidence of abnormalities was not greater among persons receiving a larger number of stings. Commercial beekeepers had a significantly greater incidence of urinary free lipids and hyaline casts, but in no case were large amounts of these substances found. The results discourage the belief that chronic honeybee venom administration is associated with any clinical disease in humans.  相似文献   

18.
19.
Five distinct proteins with allergenic activity have been isolated from short ragweed pollen. We initially tested three of these, AgE, AgK, and Ra3, for reactivity with IgE antibodies by leukocyte histamine release and by the radioallergosorbent test (RAST). We found highly significant correlations between the reactivities of these allergens by leukocyte histamine release and by the RAST, consistent with the view that both procedures detected comparable allergenic activity. We next tested the allergenic cross-reactivity of all five ragweed allergens. AgE, AgK, Ra3, Ra4, and Ra5, by RAST inhibition. With solid-phase AgE the only nonhomologous inhibitor was AgK, which cross-reacted weakly and required a 140-fold mass excess of AgK compared to AgE. With solid-phase AgK both AgK and AgE produced significant inhibition; AgE was slightly more potent than the homologous AgK, Ra3 and Ra5 were allergenically unique, because only the homologous allergen produced 50% inhibition. Ra4 was weakly inhibited by AgE, Ra3, and Ra5 when these allergens were added in 300- to 5---fold mass excesses; this weak inhibition may represent either cross-reaction or cross-contamination. We found that RAST inhibition could be used as an assay for the individual ragweed allergens and we demonstrated the presence of all of the allergens in a whole ragweed extract. The sensitivity of the RAST inhibition assay ranged from 10 ng to 100 ng for 50% inhibition. Finally, the solid-phase ragweed allergens were used to determine the frequency of elevated IgE antibody levels in 65 patients with ragweed hay fever. Virtually all of the patients reacted with AgE (97%), while 88% reacted with AgK, 51% reacted with Ra3, 28% reacted with Ra4, and 17% reacted with Ra5. These results highlight the usefulness of the RAST as a specific and sensitive tool for immunochemical studies of allergens.  相似文献   

20.
Depression appears to be common in patients with tardive dyskinesia (TD), and we hypothesized that this refractory movement disorder might respond to antidepressant treatment. We treated 19 TD patients with tricyclic antidepressant therapy supplemented within two to three weeks with lithium carbonate. All patients fulfilled the Research Diagnostic Criteria for major depressive disorder, although seven of them denied being dys phoric. The Abnormal Involuntary Movement Scale and the Hamilton Rating Scale were used to measure dyskinesia and de pression, respectively. Of the 19 patients, 11 (58%) experienced moderate or marked improvement in both dyskinesia and de pression. The authors conclude that treatment with a tricyclic antidepressant and lithium may alleviate tardive dyskinesia in patients with depressive symptoms.  相似文献   

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