Dataset Information

Analysis of allergen specific IgE cut points to cat and dog in the Childhood Allergy Study.

ABSTRACT:

Background

The application of a single allergen specific IgE (sIgE) cut point, such as 0.35 kU/L, to determine sensitization for all allergens may be suboptimal.

Objectives

To analyze self-reported symptoms suggestive of dog and cat allergy in relation to the test performance characteristics of low level, but reliably detectable, sIgE and to compare these cut points to the traditional 0.35-kU/L cut point.

Methods

Interviews and blood samples were collected among 564 young adult participants of a general risk birth cohort. Data collected from the participants' parents were analyzed as validation populations. A history of symptoms consistent with allergy on exposure to pets was obtained by standardized questionnaire. Allergen sIgE levels for dog and cat were evaluated with Pharmacia CAP. Receiver operating characteristic curves were constructed and the performance characteristics of the traditional sIgE cut point of 0.35 kU/L were compared with cut points as low as 0.1 kU/L.

Results

Using the Youden J criteria, based on the highest sum of sensitivity and specificity for a diagnostic test, cut points of 0.12 kU/L for cat and 0.2 kU/L for dog were identified as performing optimally among the participant population. In 2 validation populations, consisting of the participants' mothers and fathers, the performance of these alternative cut points were superior or similar to the traditional 0.35-kU/L sIgE level.

Conclusions

Accurately measured sIgE at levels approaching the lower limit of detection of current assays may be useful in confirming sensitization. Optimal clinical application of these tests will continue to require careful integration of the result and the strength of the patient's history.

SUBMITTER: Linden CC

PROVIDER: S-EPMC3072074 | biostudies-literature | 2011 Feb

REPOSITORIES: biostudies-literature

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Publications

Analysis of allergen specific IgE cut points to cat and dog in the Childhood Allergy Study.

Linden Carey C CC Misiak Rana T RT Wegienka Ganesa G Havstad Suzanne S Ownby Dennis R DR Johnson Christine C CC Zoratti Edward M EM

Annals of allergy, asthma & immunology : official publication of the American College of Allergy, Asthma, & Immunology 20110201 2

<h4>Background</h4>The application of a single allergen specific IgE (sIgE) cut point, such as 0.35 kU/L, to determine sensitization for all allergens may be suboptimal.<h4>Objectives</h4>To analyze self-reported symptoms suggestive of dog and cat allergy in relation to the test performance characteristics of low level, but reliably detectable, sIgE and to compare these cut points to the traditional 0.35-kU/L cut point.<h4>Methods</h4>Interviews and blood samples were collected among 564 young a ...[more]

PMID: 21277517

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Project description:IntroductionProphylactic strategies to prevent the development of allergies by establishing tolerance remain an unmet medical need. We previously reported that the transfer of autologous hematopoietic stem cells (HSC) expressing the major timothy grass pollen allergen, Phl p 5, on their cell surface induced allergen-specific tolerance in mice. In this study, we investigated the ability of allergen-expressing immune cells (dendritic cells, CD4+ T cells, CD8+ T cells, and CD19+ B cells) to induce allergen-specific tolerance in naive mice and identified CD19+ B cells as promising candidates for allergen-specific cell therapy.MethodsFor this purpose, CD19+ B cells were isolated from Phl p 5-transgenic BALB/c mice and transferred to naive BALB/c mice, pre-treated with a short course of rapamycin and an anti-CD40L antibody. Subsequently, the mice were subcutaneously sensitized three times at 4-week intervals to Phl p 5 and Bet v 1 as an unrelated control allergen. Allergen-expressing cells were followed in the blood to monitor molecular chimerism, and sera were analyzed for Phl p 5- and Bet v 1-specific IgE and IgG1 levels by RBL assay and ELISA, respectively. In vivo allergen-induced lung inflammation was measured by whole-body plethysmography, and mast cell degranulation was determined by skin testing.ResultsThe transfer of purified Phl p 5-expressing CD19+ B cells to naive BALB/c mice induced B cell chimerism for up to three months and prevented the development of Phl p 5-specific IgE and IgG1 antibody responses for a follow-up period of 26 weeks. Since Bet v 1 but not Phl p 5-specific antibodies were detected, the induction of tolerance was specific for Phl p 5. Whole-body plethysmography revealed preserved lung function in CD19+ B cell-treated mice in contrast to sensitized mice, and there was no Phl p 5-induced mast cell degranulation in treated mice.DiscussionThus, we demonstrated that the transfer of Phl p 5-expressing CD19+ B cells induces allergen-specific tolerance in a mouse model of grass pollen allergy. This approach could be further translated into a prophylactic regimen for the prevention of IgE-mediated allergy in humans.

Dataset Information

Analysis of allergen specific IgE cut points to cat and dog in the Childhood Allergy Study.

Background

Objectives

Methods

Results

Conclusions

Publications

Analysis of allergen specific IgE cut points to cat and dog in the Childhood Allergy Study.

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