Detection of specific immunoglobulin E in patients with toxoplasmosis

Abstract

An immunocapture assay was developed to detect Toxoplasma gondii-specific immunoglobulin E (IgE) in sera from adults with acute acquired infection or reactivation and from babies with congenital toxoplasmosis. The components of this assay were monoclonal antibody to human IgE, samples from patients, and T. gondii tachyzoites treated with Formalin. When T. gondu-specific IgE antibodies were present, visually detectable agglutination occurred. Sera, umbilical cord blood, fetal blood, cerebrospinal fluid, and amniotic fluid were tested by this method. Specific IgE antibodies were detected in sera from 25 (86%) of 29 adults who developed specific IgG antibody during pregnancy or had specific IgA and IgM antibodies. Specific IgE was present early during infection, at the time that IgM antibodies were present, and slightly preceding the presence of specific IgA antibodies. In 23 patients tested serially, IgE antibodies never persisted for longer than 4 months. No nonspecific anti-T. gondii IgE was detected in sera from uninfected individuals. Maternal IgE antibodies did not cross the placenta. In sera of patients with congenital toxoplasmosis, specific IgE antibodies were found at birth, during the first year of life, and during immunologic recrudescence following discontinuation of pyrimethamine-sulfonamide therapy. The IgE immunocapture assay is simple to perform. It is especially useful for determining when T. gondu was acquired by recently infected pregnant women.

Evaluation of a commercial IgE ELISA in comparison with IgA and IgM ELISAs, IgG avidity assay and complement fixation for the diagnosis of acute toxoplasmosis

“…IgE ELISA shows lower sensitivity than IgM assays [29][30][31], but the present study shows that, as with IgA, decreased sensitivity is not necessarily caused by failure to form these antibodies, and can also be caused by delayed or early cessation of antibody production, resulting in IgE antibodies being undetected during sample collection. Of all the antibody classes, IgE has the shortest duration, with positive results for up to 6 months following onset of symptoms, but this period can vary from 3 -5 months to 11 months [31][32][33][34]. Foudrinier et al [30] described two different kinetic patterns in asymptomatic seroconverters (short duration) and in seroconverters with overt toxoplasmosis, in which high IgE levels persist for a number of months.…”

Toxoplasma gondii infection: analysis of serological response by 2-DE immunoblotting

“…In case of IgA the reaction was more frequent in groups 1 and 2 as expected. Antibodies present in the other materials, like the amniotic £uid, the cord blood sample and the cerebrospinal £uid (CSF), reacted with the same spots [3,7,9,10,13,16,21,25,32,35] which were most frequently detected by all four immunoglobulin classes present in the patients sera. Only a few particularities were observed: Spot 1 gave positive responses exclusively with IgG.…”

Subcellular localization and quantitative analysis of Toxoplasma gondii target antigens of specific immunoglobulins G, M, A, and E

“…IgM, IgA, and IgE. IgM, IgA, and IgE fractions were obtained by immunocapture assay as described by Pinon et al (1990). We coated 96-well microtiter plates (Nunc, Polylabo Block, Strasbourg, France) with 100 p1 of anti-human IgM, IgA, or IgE monoclonal antibodies diluted respectively to 2 pg/ml, 2 pg/ml, and 2.2 pg/ml in a solution of 3% acetyl formaldehyde in acetate buffer (pH 4).…”

“…The serodiagnosis of toxoplasmosis was generally based on the detection of IgG and IgM antibodies. In addition, a diagnostic interest in IgA and IgE during acute toxoplasmosis has been recently reported (Decoster et al, 1988;Pinon et al, 1990).…”