Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Radioimmunosorbent Test”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources
PubMed1992

Detection of false seroconversions in cytomegalovirus seronegative platelet donors by serial complement fixation or IgG-specific radioimmunosorbent tests.

A panel of 421 cytomegalovirus (CMV) seronegative-platelet donors was followed using complement-fixation (CFT) and IgG-specific radioimmunosorbent tests (RIST) to detect seroconversion. During 4623 person-months of observation 2452 serum specimens were tested, and the annual rate of seroreactivity detected by RIST was 56%. However, most of the positive RIST results were followed by negative results with later serum samples. CFT seroreactivity was a poor predictor of RIST seroreactivity. The high rate of transient seroreactivity detected by RIST may have reflected the lack of absolute specificity of the test. Alternatively, the results could illustrate the difficulty of determining whether an individual harbours latent CMV infection using antibody tests when some seronegative individuals appear to be latently infected. In the light of our observations recommendations for CMV antibody testing of blood donors are proposed.

Antibodies, Viral↗
PubMed1979

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.

Asthma↗
PubMed1978

Reutilization of 125I-labelled anti-IgE antibody and paper discs in PRIST and RAST IgE determination.

In the paper radioimmunosorbent test (PRIST) anti-human IgE coupled paper discs are used for the estimation of total IgE in blood serum: in the radioallergosorbent test (RAST) allergen-coupled paper discs are used for the estimation of specific IgE in blood serum. The bound IgE or specific IgE is quantified by a 125I-labelled anti-human IgE. The non-bound 125I-labelled anti-human IgE can be collected and used in new assay. By a 4-h incubation of the used paper discs with 1 M glycine-HCl buffer (pH 2.7) the IgE-labelled anti-IgE complex can largely be removed. The paper discs treated in this manner can be used in a new assay.

Antibodies, Anti-Idiotypic↗
PubMed1977

Comparison of procedures for measurement of IgE protein in serum and secretions.

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.

Colostrum↗
PubMedDate not supplied

Immunoglobulin E in chronic middle ear effusions: conmparison of RIST, PRIST, and RIA techniques.

To investigate the possible role of allergy in otitis media with effusion (OME), the immunoglobulin E (IgE) content of 138 middle ear effusions (MEE) and paired serum samples from patients with chronic otitis media with effusion was determined. The initial 62 paired specimens were assayed for IgE by the radioimmunosorbent test (RIST), while the later 76 paired specimens were assayed for IgE by the paper radioimmunosorbent test (PRIST). When the results obtained by these two techniques were compared, it was noted that the PRIST procedure gave significantly lower IgE values for effusions than the RIST method. When the effusion-to-serum ratios (E/S ratios) were computed from the PRIST data, the E/S ratio was less than one, while RIST data gave an E/S ratio greater than one. The results obtained with the PRIST procedure were confirmed by double antibody radioimmunoassay for IgE. Thus, the PRIST procedure appears to measure the IgE content of MEE more accurately, and the results obtained by this procedure fail to support the concept of allergy as a major causative factor in OME.

Adolescent↗
PubMed1976

Immunoglobulins in nasal secretion with special reference to IgE. I. Methodological studies.

Different ways of collecting relatively large volumes of nasal secretion with as physiological a composition as possible were studied. Nasal secretion was collected by the so-called nasal spray washing method from 5 patients with allergic rhinitis due to pollen and 5 healthy persons during a pollen-free season. The collection was performed without any provocation and following nasal provocation with histamine or allergen solution. With the radioimmunosorbent test, in which the lower limit of measurement was 0.1 units/ml, IgE could be quantified in 52 of 60 analysed secretions. IgA, IgG and albumin were demonstrated in all secretions. In the allergic patients, following histamine and allergen provocation, a relative increase in the concentration of IgE and albumin and a significant decrease of the IgA/albumin ratio in nasal secretion was found. In the healthy subjects, such changes in the secretion were observed only after histamine provocation. Calculations also suggested some local production of IgE, but not at all of the same order of magnitude as of IgA.

Adult↗
PubMed1979

Analysis of the serum IgE levels in nonimmunized rats of various strains by a radioimmunoassay.

An assay, the paper radioimmunosorbent test (PRIST) for the measurement of total serum IgE in the rat, that allows the measurement of IgE down to a level of 0.25 ng/ml, is described. With this assay it has been demonstrated that significant differences exist in normal serum IgE levels in non-immunized rats. These differences are strain-dependent, and strains may be classified as to low (less than 50 ng/ml), medium (50--300 ng/ml) or high (greater than 300 ng/ml) serum levels. The serum IgE level is not sex-dependent. Environmental factors have a pronounced influence, optimal housing conditions resulting in low and stable levels while suboptimal conditions result in high levels with great fluctuations. Hybridization experiments suggest a multigenic control, with low IgE strains having a dominating suppressor effect.

Age Factors↗
PubMedDate not supplied

Radioimmunoassay of IgE in middle ear effusions.

Fifty-six sample pairs of middle ear effusions and sera obtained from patients with otitis media with effusion were investigated for The IgE antibody activity against mites, using radioallergosorbent test (RAST) which was recently developed as an in vitro allergy test. The IgE concentrations were also determined by radioimmunosorbent test (RIST). Results showed that the IgE antibody activity against this allergen was found in 5 middle ear effusions and 3 sera. Four of 5 patients with the positive RAST test had nasal allergy or signs suggesting allergy. Theree were two middle ear effusions which seemed to be an allergic fluid. However, findings in the present study do not suggest that middle ear effusions result from the direct allergic reaction induced by mites in the mucous membrane lining the middle ear cavity.

Acute Disease↗
PubMed1975

Measurement of absolute amounts of antigen-specific human IgE by a radioallergosorbent test (RAST) elution technique.

A technique for the absolute quantification of antigen-specific human IgE is described. It employs elution of a calculable amount of antigen-specific IgE from an allergosorbent-antibody complex by means of alkaline pH treatment, followed by measurement of the IgE content of the eluate with a modified radioimmunosorbent test (RIST). With this method IgE antibody directed against the benzylpenicilloyl determinant of penicillin (BPO) was measured quantitatively in sera from seven penicillin allergic patients. IgE specific for ragweed antigen E was measured in sera from 33 ragweed allergic patients. Values obtained for IgE anti-BPO ranged from 19 to 1806 ng/ml and comprised from 1.3 to 27.5% of total serum IgE. Values of IgE anti-antigen E ranged from 9 to 1807 ng/ml, comprising from 3 to 84% of total serum IgE. Excellent correlation (r = 0.99; p less than 0.001) was obtained for both antigen systems between values determined by the RAST elution technique and by simple RAST assay with interpolation from a reference serum of known specific IgE content as determined by the elution technique may be needed only for primary standardization of reference sera.

Allergens↗
PubMed1977

IgE studies on respiratory tract allergies.

The IgE content was determined and specific IgE antibodies were identified in serum samples and nasal secretions of 40 control subjects, 103 patients with nasal allergy, and 37 patients with bronchial asthma using a radioimmunosorbent test an both the serum samples and nasal secretions of allergic patients. Approximately 70% of the serum samples and nasal secretions obtained from patients with positive house dust skin test results were found to contain specific IgE antibodies to mites. The results of this study proved the usefulness of the determination of IgE and specific IgE antibodies in the diagnosis and study of the pathogenesis of respiratory tract allergies. The IgE in nasal secretions was much more closely related to pathogenesis of respiratory allergies than was IgE in serum samples. However, unless more concentrated nasal secretions are assayed, the diagnostic value is limited.

Adolescent↗
PubMed1992

Strong serum inhibition of specific IgE correlated to competing IgG4, revealed by a new methodology in subjects from a S. mansoni endemic area.

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.

Animals↗
PubMed1976

Comparison of serum IgE determination by radioimmunoassay and by single radial immunodiffusion.

Two commercially available methods of total serum IgE determination have been evaluated, viz: the radioimmunosorbent test (RIST) and the assay by single radial immunodiffusion (RID). RIST was found a suitable and rapid method for the wide range of IgE concentrations to be expected in the sera of an allergic population. The RID method has a lower limit of detection of about 1000 I.U./ml; over this value, both techniques provided statistically correlated results. However, for technological reasons RID was considered less suitable for routine application.

Asthma↗
PubMed1975

A critical search for evidence of changes in levels of circulating IgE in patients with cancer.

Serum-IgE levels in 95 patients with various advanced malignant conditions were determined by the radioimmunosorbent test. The results obtained did not support the claims of other workers that a high proportion of untreated cancer patients have extremely high circulating IgE levels, attributable to the release of a tumour constituent which interferes with this radioimmunoassay procedure.

Blood Donors↗
PubMed1992

[Visagnost--a strip test for in vitro allergy diagnosis in comparison with Magic Lite and Cap-FEIA: I. Total IgE determination].

The diagnosis of allergic airway diseases, especially allergic rhinitis, is based on medical history, clinical examination and further tests. Since the detection of IgE, total IgE in serum has become a major tool in the diagnosis of immediate allergy. Although in-vivo-tests like skin prick test are performed in almost every allergologist's practice, the capability of determining IgE was restricted to special laboratories. As shown for semiquantitative glucose dipsticks, a rapid and easy method has advantages for both patient and doctor. A recently developed dipstick test (Visagnost, in U.S. Quidel allergy screen) for allergy screening now enables every practitioner to determine total IgE levels within less than one hour. For the evaluation of the diagnostic value of this dipstick test, we compared the total IgE levels in the sera of 56 patients with two modern methods (Magic Lite, Ciba-Corning, and Cap-FEIA, Pharmacia). Visagnost is an enzyme-immuno-assay with the solid phase on the dipstick. It can be performed in serum, plasma or whole blood, in this study the test was performed in serum. Magic lite is a combined solid-liquid-phase immuno-assay with a final chemiluminescent reaction, the incubation time is about two hours. Cap-FEIA is a solid phase sandwich ELISA with a fluorescent reaction and an incubation time of at least four hours. Patient's sera were shock-frozen in liquid nitrogen and stored at -80 degrees C until examination. Visagnost gave results in four ranges of minor 20 U/ml, 21-50 U/ml, 51-100 U/ml and more than 100 U/ml.(ABSTRACT TRUNCATED AT 250 WORDS)

Enzyme-Linked Immunosorbent Assay↗
PubMed1977

The effect of orally administered sodium cromoglycate on symptoms of food allergy.

A comparison was made between the effects of sodium cromoglycate (SCG) and placebo on symptoms of food allergy in twenty children. Both the clinician's and patient's preferences and the clinician's evaluation of the specific response to challenge showed a significant benefit from SCG. A striking effect on skin symptoms was seen in some children and the recorded mean score for skin symptoms was lower after 2 weeks' treatment with sodium cromoglycate. However, the differences detected from the mean symptom scores were not statistically significant. Neither were there any significant changes in the IgE, IgG, IgA and IgM food allergen antibody levels related to the treatment.

Adolescent↗
PubMed1978

The specificity of radiostaining in crossed radioimmunoelectrophoresis.

The major allergen from codfish (DS 22) was used to study specific and non-specific radiostaining in crossed radioimmunoelectrophoresis (CRIE). Various modifications of CRIE experiments were performed including experiments where immunoprecipitates in agarose were transferred to test tubes and the radioactivity was measured in a gammacounter. The degree of non-specific binding of IgE and 125 I-anti-IgE to the percipitates was low. A linear relation was found between the amount of human serum IgE antibody used in CRIE and the degree of radiostaining obtained. Increasing the amount of DS 22 in the precipitates from 0.31 to 2.5 microgram resulted in a moderate increase in the uptake of 125 I-anti-IgE, whereas further increase of the amount of DS 22 (5--10 microgram) resulted in reduced uptake of isotope. Serum from a patient containing IgE antibodies to rabbit serum gave rise to radiostaining over the entire antibody-containing gel area, and it is suggested that such human sera be avoided when using CRIE.

Allergens↗