Comparison of IgE values as determined by different solid phase radioimmunoassay methods

Usefulness of specific IgE antibody tests: a progress report

LEARNING OBJECTIVES

To enable the readers to recognize some of the history, problems, progress, interpretation, and present status of assays for specific IgE (s-IgE) antibodies.

DATA SOURCES

Peer-reviewed literature in the field.

STUDY SELECTION

Key articles were selected by the author.

RESULTS

Clinical and analytical studies have differed widely in their conclusions as to the performance of tests for s-IgE. Study conclusions depend on the testing method used, the allergen(s) studied, patient selection, and, most importantly, the standards used for comparison. Today, only a handful of the once commercially developed assays still exist, and some of these still do not compare well to an analytical ideal standard. However, with the extent of regulation and economic pressures, most of the surviving s-IgE tests are considerably improved over what had existed before them.

CONCLUSIONS

Allergic diseases with multiple symptom patterns seem to be increasing in modern societies. Objective methods are needed to differentiate allergic origins from other mechanisms that cause similar symptoms. Accurate, quantitative, and objective methods for s-IgE measurement are now available and can be used effectively in clarifying allergic diagnoses when interpreted in conjunction with the clinical history.

Serum IgE levels during the first 6 years of life

OBJECTIVE

Total serum IgE percentiles were derived for a population-based sample of 4082 white children from Germany by weighted analysis of measurements from the Multicenter Allergy Study cohort.

METHODS

The children of a prospective birth cohort were selected from a complete 1-year sample of newborns in 6 obstetric departments in 1990. Total IgE was determined at 1, 2, 3, 5, and 6 years of age in 1160 newborns of the cohort. By weighting these measurements for sex, atopic family history, and elevated cord blood IgE, total serum IgE percentiles were estimated for the original population-based sample of 4082 children.

RESULTS

IgE levels increased by age (P <.0001). We found statistically significant higher total IgE values in boys than in girls at each age (P <.05). Within the group of atopic children, this sex difference was not statistically significant.

CONCLUSION

Our estimates of total serum IgE levels for a large population-based sample were lower than most values previously reported. We suggest that for both clinical and epidemiologic and genetic studies, IgE values should be expressed with percentiles.

Relation between airway responsiveness and serum IgE in children with asthma and in apparently normal children

BACKGROUND

Although asthma diagnosed by a physician is known to be related to serum IgE levels, it is not known whether there is a relation between the level of IgE and airway hyperresponsiveness to a methacholine challenge. The characteristics of asymptomatic persons that predispose them to airway hyperresponsiveness are also unknown.

METHODS

We studied the relation between the serum total IgE level and airway hyperresponsiveness in the presence or absence of asthma and other atopic diseases in a birth cohort of children. Data from a questionnaire regarding respiratory symptoms, plus measurements of the serum total IgE level and airway responsiveness to inhaled methacholine, were obtained for 562 11-year-olds in New Zealand.

RESULTS

The boys had a higher prevalence than the girls of current diagnosed asthma (13 percent vs. 6 percent), current symptoms of wheezing (22 percent vs. 15 percent), and airflow obstruction at base line (6 percent vs. 1 percent) and had a wider distribution of IgE levels, although mean IgE levels (120.8 IU per milliliter in the boys and 98.1 IU per milliliter in the girls) did not differ significantly between the sexes. The prevalence of diagnosed asthma was strongly related to the serum IgE level (P for trend less than 0.0001). No asthma was reported in children with IgE levels less than 32 IU per milliliter, whereas 36 percent of those with IgE levels greater than or equal to 1000 IU per milliliter were reported to have asthma. This relation with the serum IgE level was not explained by a concomitant diagnosis of allergic rhinitis or eczema. Airway hyperresponsiveness to a methacholine challenge also correlated very highly (P less than 0.0001) with the serum IgE level. This relation remained significant even after the exclusion of children with diagnosed asthma (P less than 0.0001) and of all children with a history of wheezing, allergic rhinitis, or eczema (P less than 0.0001).

CONCLUSIONS

Even in children who have been asymptomatic throughout their lives and have no history of atopic disease, airway hyperresponsiveness appears to be closely linked to an allergic diathesis, as reflected by the serum total IgE level.

Association of MS Pi phenotype with airway hyperresponsiveness

Asthmatic families (AFs) and normal families (NFs) were studied to determine the relationship between bronchial hyperresponsiveness and alpha 1-antitrypsin protease inhibitor phenotype. We studied IgE levels, skin test scores, and methacholine sensitivity. In both the AF and NF groups, the subjects with the MS phenotype had significantly greater methacholine-induced bronchial hyperresponsiveness sensitivity than the MM and MZ subjects. These findings suggest that the S allele may be associated with bronchial hyperresponsiveness.

Neonate blood IgE levels on filter paper as indicators of atopic disease

Measurements of IgE levels in the blood of neonates were investigated using filter paper for blood collection in mass screening of congenital metabolic disorders. Time-resolved fluoroimmunometric assay system for the measurement of filter paper blood IgE levels was also studied. In an analysis of the present results, IgE values of at least 0.015U/ml, the measurement limit, were considered as high. High IgE levels in filter paper blood were seen in 28 (7.2%) of the 389 cases. When the relation with serum IgE levels at 18 months of age was investigated in 134 of 389 subjects, high serum IgE levels were also found in about 86.7% of the subjects with high IgE levels in filter paper blood. In addition, when the relation between family history of atopic disease and presence of atopic disease in the first 18 months of age was investigated in 203 of the 389 subjects, about 90% of the subjects with a family history of atopic disease and high IgE levels in filter paper blood developed atopic disease. Since filter paper blood is routinely collected in Japan, IgE levels in this blood should be widely checked for the prediction of onset of atopic disease in infants.

IgE antibodies to Pityrosporum orbiculare in children with atopic diseases

IgE antibodies to Pityrosporum orbiculare and 16 other species of fungi were measured with the radioallergosorbent test (RAST) in sera of 131 children. The children were 7-18 years old, suffered from atopic diseases and showed a varied allergic profile on a skin prick test (SPT). IgE antibodies to P. orbiculare were found in the sera of 26 of the 131 children. A higher proportion of the P. orbiculare RAST positive children than of the negative ones had current eczema (p less than 0.0001). In a stepwise logistic regression analysis of SPT and RAST data, the occurrence of serum IgE antibodies to P. orbiculare had the highest explanatory value for current eczema. Ten of 15 children with current atopic eczema and total serum IgE of greater than 500 kU/l had serum IgE antibodies to P. orbiculare. Twenty-four of the 26 P. orbiculare RAST positive children harboured serum IgE antibodies to other fungi. The strong relationship between atopic eczema and the occurrence of IgE antibodies to P. orbiculare indicates that these antibodies may be pathogenetically important in at least some patients with atopic eczema and this gives another dimension to this common skin disease.

Serum IgE in non-atopic adults and in dermatitis patients

Total serum IgE was determined with the PRIST technique, and specific reaginic antibodies against 10 allergens were measured in 163 healthy adults with no personal or family history of symptoms indicative of atopy (Group A). 103 non-atopic adults with a family history of atopic diseases were similarly investigated (Group B). When all subjects who at the second interview presented with a history of atopic symptoms and those with positive RAST results were excluded, the geometric mean serum IgE value for Group A was 14.5 (SD = 2) - 94.4 U/ml and for Group B 14.4 (SD = 2) - 130.2 U/ml. There was no significant difference in the IgE values between men and women. Subjects under 40 years of age had significantly higher IgE values than subjects over 40 years. In the series of 276 dermatitis patients the geometric mean IgE value for the men was significantly higher (46.8) than for the women (28.8 U/ml). There was a highly significant difference in the mean serum IgE levels between the patients with a personal history of atopic diseases and the other patients. Patients with present atopic disease had significantly higher mean IgE values than those with past atopic disease while no significant difference was discernible in the mean IgE levels between the non-atopic patients from atopic families and those with no personal and family atopy. Three years later, total serum IgE was controlled in subjects with initial IgE levels greater than 100 U/ml. During this time, eight subjects had developed an atopic disease. In most cases, there were only slight variations in the IgE values.

Influences of neonatal serum IgE concentration, family history and diet on the incidence of cow's milk allergy

Serum IgE concentration was measured on the 5th day of life in 943 infants. All infants were included in a 3 month follow-up study. The frequency of cow's milk allergy was studied according to either family history, IgE level, or both. Feeding (mother's milk or formula feeding) was taken into account. Manifestations suggestive of food allergy were hardly observed in breast-fed babies. In the formula-fed group a positive family history correlated with a 40% incidence of allergic manifestations, compared to a 13% incidence (P less than 0.001) in the group with negative family history. A high IgE level (IgE greater than 1.3 U/ml) indicated a 43% risk of developing allergic manifestations in formula-fed babies as compared to 15% (P less than 0.001) in the group with normal results of a screening test. Frequency of allergic manifestations in a subgroup with a negative family history and a high IgE level (38%) was equal to the frequency in the subgroup with a positive family history and negative screening test results (IgE less than 1.3 U/ml)(36%). The incidence in the subgroup with both positive screening test results and a positive family history was 49%. None of these differences were significant. The frequency in the subgroup with both parameters negative was 8% (P less than 0.001 to 3 other subgroups). Our results indicate that the family history seems to correlate as well with the incidence of allergic manifestations as the neonatal serum IgE concentration.(ABSTRACT TRUNCATED AT 250 WORDS)

Diagnostic tests in allergy to green coffee

Twenty-two coffee roastery workers with work-related symptoms of various degree from the eyes, nose or bronchi were tested with partly purified water-soluble extract from dust of green coffee beans (GCB). Eighteen persons had a positive prick test, eight a positive bronchial provocation test and seven a positive nasal provocation test. Fourteen had a positive methacholine test, indicating unspecific bronchial hyperreactivity. Specific IgE antibodies to GCB extract were found in sera of 11 workers and to castor bean (CB) extract in 16. The workers measured their lung function with an air flow meter, three times a day for 1 week, and the values were lower in the second half of the week for the workers with IgE antibodies to GCB, but not for the others. It is concluded that the case history, prick test, RAST, and simple lung function tests for one or a few weeks are the best tools when investigating occupational allergy. When the allergen is unknown, but the occurrence of an IgE-mediated allergy is suspected, serial lung function measurements and determinations of total serum IgE, in addition to taking a careful case history, are valuable methods with which to start the investigation.

Immunoglobulin E assayed after pepsin digestion by an automated and highly sensitive particle counting immunoassay: application to human cord blood

We describe in this article a fully automated, universal assay for serum IgE after pepsin digestion of the sample and subsequent assay of the released Fc" epsilon fragment by particle counting immunoassay (PACIA). The sensitivity and the range of the assay were easily modulated by changing the concentration of dextran in the reaction medium. In the application to cord serum, the sensitivity reached 0.1 IU/ml in 30 min incubation time and with a throughput of 50 analyses per hour. Within-day and between-day coefficients of variation did not exceed 7.6% for IgE levels covering a wide range of the standard curve. Dependable accuracy was demonstrated by linearity tests, analytical recoveries (89% to 112%), and correlation with PRIST on 48 samples from children ages 1 to 14 yr (y = 0.97x + 5.92; r = 0.987). Minor discrepancies between the two methods were attributed to a slight serum effect in PRIST. PACIA applied to 348 cord serum samples demonstrated a statistically significant influence of sex and race on the cord IgE level. In European neonates boys had significantly (p = 0.019) higher geometrical mean cord IgE levels (n = 142; 0.46 IU/ml; range less than 0.10 to 30 IU/ml) than girls (n = 146; 0.33 IU/ml; range less than 0.10 to 8.0 IU/ml), which was attributed to a predominance of boys (chi 2 = 4.29; p less than 0.05) having more often elevated cord IgE (less than 1.20 IU/ml) than girls. Neonates of African-Asian origin had significantly (p less than 0.00005) higher cord IgE levels (n = 60; 1.05 IU/ml; range less than 0.10 to 125.0 IU/ml) than European neonates (n = 288; 0.39 IU/ml; range less than 0.10 to 30.0 IU/ml).

Insect allergy. A comparative study including case histories and immunological parameters

One hundred and seventeen persons all stung by yellow jacket (YJ) and/or bee were examined by means of skin prick test with venom of these insects, skin prick test with 10 inhalant allergens and analyses of total IgE, specific IgE and IgG against honey bee and YJ venom. Eighty-seven persons had had a systemic reaction to YJ or bee sting, the rest had reacted normally or with a large local reaction. Positive correlations (P less than 0.05) were found between results of skin prick tests and specific IgE against venoms and, for YJ, between the severity of symptoms after sting and the size prick test with the venom. That some of the more severe symptoms could have been caused by non-immunological mechanisms could explain why a significant correlation was present only between the results of the prick test and specific IgE and not between these tests and the clinical symptoms. Specific IgE values against YJ and honey bee venom showed covariation, although no correlation could be demonstrated between the clinical symptoms after stings from these insects, or between skin prick test results using the two different extracts. The severity of the sting reactions was not correlated to age, atopic disposition, amount of total IgE, number of stings during life, or positive skin prick test to inhalant allergens. It is concluded that in insect allergy, specific IgE analysis and skin prick tests are supplementary.

Bee keepers' IgG and IgE antibody responses to bee venom studied by means of crossed radioimmunoelectrophoresis

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.

Respiratory virus infections and aeroallergens in acute bronchial asthma

Two hundred and fifty six attacks of acute bronchial asthma occurring in 169 children aged over 2 years were studied during a two year period. More attacks occurred during spring and autumn than at other times of the year. In 73 patients (29%) a respiratory virus infection was diagnosed, with the same seasonal variation as the asthmatic attacks. Most of the virus infections were caused by rhinovirus (45%) and respiratory syncytial virus (19%). There was no significant correlation between asthmatic attacks in patients with birch pollen, grass pollen, or Cladosporium herbarum allergy and counts of the respective pollen or spores in the air. More seasonal attacks occurred in patients with cladosporium allergy than in patients without cladosporium allergy but there was no seasonal variation among birch or grass pollen allergic patients. Information about exposure to animals was obtained in only 12% of attacks occurring in 121 patients with allergy to animal dander. The single precipitating factor most frequently associated with acute asthma was respiratory virus infection.

The development of a rapid ELISA for IgE utilizing commercially available reagents

An enzyme-linked immunosorbent assay (ELISA) for human immunoglobin E (IgE) has been developed. To coat the polystyrene tubes (the solid phase) an antibody concentration of 6 mg/l in sodium carbonate buffer, pH 9.8, at 37 degrees C for 24 h was found superior to other conditions. The maximum amount of globulin adsorbed to the polystyrene surface was estimated to be 2.7 mg X m-2. This is consistent with a monolayer being adsorbed. While some of the anti-IgE molecules are inactivated during adsorption, the remaining molecules, once adsorbed, appear to retain activity for extended periods, and the coated tubes were stable for several weeks. Kinetic studies of the association of analyte, of antibody-enzyme conjugate and enzymic catalysis were used for the optimisation of the assay and allowed us to reduce assay time to 6 h. The association of analyte to the coated tube and the association of anti-IgE-peroxidase conjugate to bound IgE, in the present design, had T1/2 of approximately 0.5 h. Equilibrium is not obtained. The dissociation of analyte, surprisingly, was nearly undetectable. At least one of the two antibodies employed in the sandwich assay, preferably the anti-IgE-peroxidase conjugate, should be free of non-specific antibodies in order to eliminate non-specific reactions. The influence of serum matrix was eliminated by diluting serum samples and standards 1:21 in buffer. For the assay of very low concentrations (i.e. less than 10 kIU/l) standards produced in IgE-free serum are required to compensate the influence of matrix. Comparison with a commercial kit (Hoechst-Behringwerke, Frankfurt/Main, FRG) showed good agreement. All reagents are commercially available and the assay is well suited for routine use.

Total serum IgE concentrations in adolescents and adults using the phadebas IgE PRIST technique

Total serum IgE measured with the Phadebas PRIST technique was titrated in 117 normal non-allergic subjects, 237 allergic adolescents or adults and 89 non-allergic patients who suffered from asthma, rhinitis, or conjunctivitis. All subjects were of Caucasian origin. In normal subjects, mean total serum IgE was 38 +/- 43 kU/l. This value is exactly the same as that found in a study of Caucasian New Zealanders and very similar to the values found in most U.S. studies. This suggests that the mean total serum IgE concentration is remarkably constant in normal non-allergic Caucasians. The upper limit of the normal range is considered to be 150 kU/l. 38% of allergic patients have total IgE concentrations within the normal range. Some pollen or hymenoptera venom-sensitive patients have a total serum IgE concentration below 20 kU/l. The non-allergic patients had a mean IgE concentration of 94 +/- 93 kU/l, and 25% of them had a total serum IgE above the normal range. Asthmatic patients had higher mean IgE levels than those who were suffering from either rhinitis or conjunctivitis.

A solid-phase fluoroimmunoassay for human IgE

A fluoroimmunoassay (FIA) for the measurement of immunoglobulin E (IgE) is described. The method involves a sandwich technique in which antiserum to human IgE is adsorbed on a cellulose acetate/nitrate disc which is attached to a plastic StiQTM sampler. The prepared sampler is reacted with serum and antigen is bound specifically. After buffer wash and treatment with goat serum to block non-specific binding, the samplers are reacted with monospecific fluorescein conjugated antisera to human IgE. Two buffer washes remove unbound material and the fluorescence which is directly proportional to the IgE concentration is measured in a FIAX fluorometer. Assay standards range from 2 to 400 IU/ml. The method gives within run coefficients of variation (CV) from 3.3 to 8.4% and between run CV from 6.2 to 16.1% being less precise at low analyte concentrations. IgE concentrations of a group of 74 sera determined by FIA using StiQsTM prepared with antisera from 2 sources correlated well with results found by radioimmunoassay.

Determination of total IgE by ELISA in tubes and plates compared with PRIST

IgE was measured by ELISA in tubes and in microtiter plates, the results being compared with PRIST data. The recommended readings of the tube contents in a spectrophotometer (SPM) were compared with results using a multi-channel photometer (MCP). Geometric mean values (International Units) and standard deviations of 44 normal sera examined by the 3 different methods were: PRIST 16.2 +/- 4.0; SPM 15.6 +/- 4.9 and MCP 18.4 +/- 4.4. Correlation coefficients were: PRIST-SPM r = 0.98; PRIST-MCP r = 0.98; and SPM-MCP r = 0.97. Intra- and inter-assay coefficients of variation were smaller for MCP than for SPM. In addition, reading in microtiter plates was much faster, while having little effect on sensitivity.

Serum immunoglobulin E in atopic and non-atopic children aged 6 months to 5 years. A follow-up study

In order to obtain serum IgE reference values for small children we measured the total serum IgE concentration at the ages of 6 months, 1, 3, and 5 years in 66 healthy, non-atopic children who were followed from birth to 5 years of age. From this reference group we had excluded children with symptoms or signs of atopy during the follow-up period, as well as children with blood or nasal smear eosinophilia or positive skin prick tests. We also studied serum IgE levels in groups of children having latent atopy, symptomatic atopy, or severe atopic disease. We suggest that in the definition of reference values the upper limit of normal should be replaced by a zone of uncertainty, lying between the 95th and 97.5th percentiles. Serum IgE is a useful test with high specificity but low sensitivity in the differentiation between atopy and non-atopy. Thus high levels suggest atopy, while normal or low values yield little information. A normal serum IgE level does not necessarily exclude atopic disease.

Respiratory infections in the first year of life in children at risk of developing atopy

Ninety-two infants, each of whom had one parent with asthma or hay fever, were followed up from birth to age of 1 year and 72 to the age of three years. During the first year of life respiratory symptoms, eczema, and respiratory viral infections were all reported. Within the first year 24 babies developed eczema; 28 had a wheal of 1 mm in diameter or more on prick skin testing with cutaneous allergens. Forty-three children had one or both of these characteristics and formed an atopic subgroup; by the same criteria, 49 children were non-atopic. The number of respiratory infections in the two groups was not significantly different; similar viruses were isolated from both groups. These viruses were associated with both upper and lower respiratory tract infections. Wheezing was a clinical feature in 12 children during lower respiratory tract infections. Of these babies six were atopic in the first year of life. Of the six non-atopic babies, one had eczema in the second year and five children developed raised total serum IgE values within the 3 years.

Role of atopic allergy in chronic otitis media. Evaluation based on serum IgE and nasal/aural cytologic findings in patients with operated chronic ears

Serum IgE levels and nasal/aural secretion eosinophils and basophils cells were studied in 84 patients with ear discharge despite previous radical operation, in 83 patients with postoperatively dry ears, and in 30 normal persons. Serum IgE values suggesting atopy (greater than 100 U/ml, PRIST) were more frequent (p less than 0.05) among patients with draining ears than among persons with healthy ears. Normal IgE concentrations showed reversed frequency distribution. Nasal secretion eosinophils and/or basophilic cells were also found more frequently (p less than 0.05) among patients with discharging ears than in other groups. Analogously, those with both serum IgE of greater than 100 U/ml and 'positive' nasal cytology more often had infected than dry (p less than 0.01) or normal (p less than 0.05) ears. Aural secretions showed eosinophils and/or basophilic cells in 14 (17%) patients; 11 of them had such cells in their nasal secretions too. It would seem that atopy is probably one cause of persistent therapy-resistant otitis media and it must be taken into account when considering the treatment of a chronic ear.

The occurrence of immunoglobulin E in Human seminal plasma

The presence of IgE in human seminal plasma has been explored using two different radioimmunoassay methods. Samples were obtained from 84 patients under investigation for involuntary infertility. Low levels were recorded in seminal plasma (less than 0.05-805 kIU/1) together with a wide scatter of serum values (less than 0.5-956 kIU/1). The incidence of detectable seminal plasma IgE was related to high serum IgE values (P less than 0.001; chi 2-test). Among men reporting allergy problems and who has serum IgE levels above 50 kIU/1 detectable semen IgE was seen in 15 out of 18 patients. Sperm agglutination was observed in 18 men of whom 11 had detectable seminal plasma IgE. The question of whether or not seminal plasma IgE is a plasma transudate or is locally produced as well as its possible function in seminal plasma is discussed.

IgE concentrations measured by PRIST in serum of healthy adults and in patients with respiratory allergy. A diagnostic approach

In order to establish reference values for total serum IgE in an adult non-atopic population, 175 individuals, 17-85 years of age, were investigated. The usefulness of a sensitive method (PRIST) for serum IgE determinations in discriminating atopy from non-atopic conditions in allergological routine diagnosis was elucidated by investigating 445 patients with symptoms of asthma, rhinitis, urticaria and eczema. Comparisons were made with case histories, in vivo tests and circulating IgE antibodies. The geometric mean for serum IgE in the reference material was 13.2 kU/l with a 2 SD range of 1.53 to 114 kU/l. No significant difference between age groups or sexes was observed. In patients classified as non-atopic and pronounced atopic, the geometric mean values for IgE were 40, 123 and 458 kU/l respectively. The IgE level correlated with number of allergens positive in RAST and with skin test results. It is concluded that IgE determinations are of great help in discriminating atopic conditions from other diseases with similar symptoms. A serum IgE value above 100 kU/l in a patient is strong evidence for the presence of an atopic disease while a value below 20 kU/l indicates that the symptoms are due to intrinsic or infectious disease.

Clinical and immunologic effects of fractionated total lymphoid irradiation in refractory rheumatoid arthritis

Ten patients with refractory rheumatoid arthritis were given 3000 rad of fractionated total lymphoid irradiation in an uncontrolled therapeutic trial. Total lymphoid irradiation was associated with objective evidence of considerable clinical improvement in eight patients and with reduced blood lymphocyte counts in all 10. On completion of irradiation, there was an abrogation of lymphocyte reactivity in vitro in the patients with clinical responses, but abnormal antibody activities characteristic of rheumatoid arthritis and normal components of humoral immunity were not suppressed. Partial recrudescence of arthritis occurred shortly after a year after the completion of irradiation and was paralleled by a restitution of lymphocyte concentrations and responsiveness to mitogens to levels similar to those observed before irradiation. These data provide further evidence of T-cell involvement in the pathogenesis of rheumatoid arthritis and demonstrate that total lymphoid irradiation can induce temporary relief, but they do not ascertain whether the natural history of this disease was altered.

Distribution of IgE in a community population sample: correlations with age, sex, and allergen skin test reactivity

The distribution of total serum IgE determined by the paper radioimmunosorbent test (PRIST) is examined in a large random stratified community population. Prior to logarithmic conversion the distribution of this immunoglobulin is not normal, with almost 40% of values below 20 IU/ml. A normal distribution occurs following such conversion, with a geometric mean value of 32.1 IU/ml. Both age and sex, in addition to atopic status, relate to IgE level. In both sexes highest levels occur among 6- to 14-year-olds, and males have higher levels than females at any given age. Women over age 75 yr have the lowest levels (geometric mean 9.2 IU/ml). Subjects with positive skin test results have several times the concentration of IgE as their nonatopic counterparts.

Increased release of histamine by anti-IgE from leucocytes of asthmatic patients and possible heterogeneity of IgE

A study was made of the significantly increased amounts of histamine released by anti-IgE from the leucocytes of asthmatic and allergic patients, particularly in patients with a low level of serum IgE. By measuring cell-bound IgE and histamine release with anti-IgE, particularly after passive sensitization of human leucocytes, it was possible to show that serum IgE in some allergic patients differed from that in normal subjects in two respects. Firstly, it appeared to have a relatively high leucocyte binding affinity, though this could not be proved conclusively. Secondly, and more importantly, IgE of some patients could more readily mediate histamine release with anti-IgE, that is to say it had a greater efficacy. These properties should be differentiated from another feature of allergic individuals, that is the more ready releasability of histamine from the patients' own leucocytes.

Evaluation of total and specific IgE determinations in normal children and children suffering from asthmatic bronchitis with suspected allergic disease

In young children with suspected allergic disease skin testing might to some extent be replaced by total and specific IgE determinations. Total IgE levels could be determined in these cases by the paper radioimmunosorbent test (PRIST) and be related to one's own reference values. Elevated total IgE levels have some predictive meaning for the occurrence of positive radioallergosorbent tests (RAST) in allergic disorders. Therefore, if total IgE and specific IgE determinations are performed routinely, the RAST panel applied should be minimized to three or four allergens and should be performed only when related to the clinical history. This will be exemplified with the sera of children suffering from asthmatic bronchitis with suspected allergic disease.

Circulating IgE levels in patients with bronchial carcinoma

Serum IgE measurements in 107 patients with bronchial carcinoma revealed statistically significant elevations when compared to a control population. Serum IgE elevation was seen in 21.5% of the sample (23 of 107) and in all histological types at all clinical stages of the disease. It appears to occur early in the disease or possibly before the development of the carcinoma.

Serum total IgE in normal subjects and the influence of a family history of allergy

The purpose of this study was to establish the range of serum total immunoglobulin E (IgE) in a healthy population free of personal and family history of allergy, and to determine whether a family history of allergy influenced serum IgE levels. Using commercially available Phadebas reagents, the mean serum IgE in eighty-four adults aged 17-30 years with no personal or family history of allergy was found to be 38.8 iu/ml. Seventy-five percent of subjects had a serum IgE below 50 iu/ml and in only one subject was serum IgE in excess of 150 iu/ml, which we suggest be taken as the upper limit of normal. When healthy subjects with no personal history but with a family history of allergy were included with this normal population, the mean serum IgE in 207 subjects was 95.4 iu/ml and the upper limit of the distribution curve over 200 iu/ml, suggesting an influence of genetic factors on IgE production.

Comparison of cord blood immunoglobulin E concentrations and maternal allergy for the prediction of atopic diseases in infancy

Total serum IgE levels were determined in 136 newborns and their mothers and in 54 of their fathers, using the paper radioimmunosorbent test (PRIST) technique. IgE specific antibodies for house dust (Dermatophagoides pteronyssinus), orchard grass, timothy grass, and cow's milk were measured with the radioallergosorbent test (RAST). One hundred thirty-three RAST assays were negative in newborns, and in three cases RAST for cow's milk was positive. Cord blood IgE ranged from 0 to 5.5 IU/ml (mean 0.32 +/- 0.54 IU/ml); levels were significantly (p less than 0.05) higher when maternal IgE was over 100 IU/ml and when mothers had received progesterone therapy during the pregnancy. Salbutamol administration or tobacco smoking during pregnancy did not influence newborn IgE. A clinical follow-up study was conducted in 83 infants for 9 mo. Nine infants developed definite atopic disease, and possible allergic diseases were noted in eight other infants. The IgE level at birth appeared to be more predictive for the development of allergy in infancy than the family history.

IgE levels in intestinal juice

This investigation was performed to determine the possible significance of the IgE levels in intestinal secretions for the recognition of type I food allergy (immediate hypersensitivity). Four groups of individuals were studied and compared with each other: (1) healthy controls and patients with gastrointestinal disorders not affecting the small intestine; (2) patients with small intestinal disease; (3) patients with various manifestations of allergy but without food intolerance; and (4) patients with atopic sensitivity to foods. Despite the presence of proteolysis in the intestinal fluid, a statistically highly significant increase of the intestinal IgE level was observed in patients of group 4 with type I food allergy and in patients of group 3 as compared with normals. This was associated with an increase in the serum IgE level. An increased synthesis of the IgE in the lamina propria of the small intestine is most probable, but not yet adequately established.

Immunoglobulin concentration in serum and seminal fluid from men with and without sperm-agglutinating antibodies

Serum and seminal fluid from infertile men with head-to-head (H-H) or tail-to-tail (T-T) sperm-agglutinating antibodies and fertile men devoid of sperm antibodies were examined for immunoglobulin (Ig)G, IgA, IgM, IgD, and IgE. Only IgG, IgA, and IgE were demonstrated in the seminal fluid. No statistically significant differences in the serum or seminal fluid immunoglobulin concentrations were found between the fertile and the two infertile groups of men examined.

Laryngeal secretions. An immunochemical and immunohistological study

This study was designed to investigate properties of laryngeal secretion and secretory activity of IgA in the larynx. Laryngeal secretions were collected by adsorption method on filter paper during laryngomicrosurgery from 20 patients having an inflammatory lesion in the larynx. Contents of IgG, IgA, IgE, secretory component (SC), and lactoferrin in the laryngeal secretions were determined and compared with results of those in nasal secretions, tracheobronchial washings, and serum samples obtained from the same subjects. The laryngeal mucosae of 8 laryngectomized materials for cancer lesion were subjected to immunofluorescence studies including the cytoplasmic SC affinity test. Results of this study indicate that laryngeal secretions are characterized by exocrine secretion, resembling nasal and tracheobronchial secretions in the electrophoretic pattern and immunoglobulins content. The immunofluorescence studies and SC affinity test found that the larynx possesses secretory activity of IgA, particularly in the ventricle and subglottis.

A modified sandwich technique for the measurement of IgE

The paper radioimmunosorbent test (PRIST) has been described as the method of choice for determining low serum IgE levels; the radioimmunosorbent test (RIST) as the method of choice for determining normal and elevated serum IgE levels. By replacing the 125I-labelled anti-IgE antibody used in the paper radioimmunosorbent test by the 125I-labelled anti-IgE reagent used in radioallergosorbent test (RAST) and by changing the serum dilution and the incubation time, this modified sandwich technique (MST) became comparable to the RIST in the normal and elevated IgE-region and showed results similar to the PRIST in the very low IgE-region. The affinity of the 125I-labelled anti-IgE of the RAST proved to be about 2.6 times higher than the antibody used in the PRIST, which explains the improved results in the normal and the good results in the very low IgE-region. The lowest serum IgE level measurable by this method was as low as 0.05 I.U./ml, as determined in 20 cord sera. The mean IgE level in cord sera was 0.45 I.U./ml (range 0.05--2.63 I.U./ml). The results of this study suggest replacement of the antiserum used in PRIST by the one available for RAST.