Article

Characterization of occupational sensitization by multiallergen immunoblotting in workers exposed to laboratory animals.

Department of Immunology, Hospital Carlos III, Madrid, Spain.
Annals of allergy, asthma & immunology: official publication of the American College of Allergy, Asthma, & Immunology (Impact Factor: 3.45). 03/2012; 108(3):178-81. DOI: 10.1016/j.anai.2012.01.007
Source: PubMed

ABSTRACT Studies have estimated that 10% to 23% of workers exposed to laboratory animals report symptoms of laboratory animal allergy.
To determine the level of occupational sensitization in workers exposed to laboratory animals and to develop a diagnosis system based on a multiallergen IgE immunoblot.
A total of 75 workers exposed to laboratory animals were initially studied with skin prick tests performed with animal epithelia extracts. The workers with suspected occupational disease and positive skin prick test results were further studied with the ImmunoCAP system to determine specific IgE levels to urine and epithelia allergens and with multiallergen IgE immunoblotting to detect specific IgE levels to epithelia allergens and bovine serum albumin.
Twenty of the 75 workers were studied with ImmunoCAP and multiallergen IgE immunoblotting. Nine were polysensitized and 3 were sensitized to only one animal. The results obtained by ImmunoCAP and multiallergen IgE immunoblotting were concordant except for in 3 workers, who had low or negative values of specific IgE determined by ImmunoCAP but positive allergen detections by immunoblotting. On the basis of the results of the study and the clinical symptoms related by workers, 16% were diagnosed as having occupational allergy.
Multiallergen immunoblotting by means of a unique test offers a graphic representation of sensitization to the different animals to which workers are exposed, providing additional information on the clinical symptoms caused by the involved allergens. The results presented suggest that this system can improve the diagnosis of laboratory animal allergy by obtaining a sensitization profile for each exposed worker.

0 Bookmarks
 · 
125 Views
  • [Show abstract] [Hide abstract]
    ABSTRACT: To evaluate recent data on the causative role of specific IgE antibodies, as well as the performance of IgE diagnostic tests, in allergic occupational asthma induced by high (HMW) or low-molecular-weight (LMW) agents. Skin prick testing (SPT) and specific IgE assays are useful to document allergy to most HMW allergens and some LMW agents. These tests, however, are limited by the lack of standardized and commercially available reagents. There is a wide variability among the quality of occupational allergen extracts used for SPT and the sensitivity of several SPT solutions is low. In addition, many individuals with allergen-specific serum IgE and/or positive SPT to specific HMW allergens do not have clinical symptoms. Sensitization or allergenic cross-reactivity to allergens or epitopes from unrelated sources may interfere in the diagnosis of IgE-mediated allergy, giving rise to false-positive results, particularly when cross-reactive carbohydrate determinants (CCDs) are involved. The immune responses to these ubiquitous structures may interfere with the diagnosis of occupational allergy. Component-resolved diagnosis of IgE-mediated allergic diseases (occupational and nonoccupational) using panels of native or recombinant allergens, or micro-arrayed allergens, have been proposed to identify specific molecules responsible for these disorders and to overcome false-positive in-vitro test results. Improvement and standardization of SPT solutions for occupational allergens are highly recommended. More refined diagnostic tools than specific IgE measurements are being developed, such as inhibition assays of IgE binding to CCDs with specific carbohydrate molecules, and component-resolved diagnosis.
    Current Opinion in Allergy and Clinical Immunology 02/2014; · 3.40 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: BACKGROUND: Rabbits are increasingly kept as domestic pets. Several rabbit allergens have been characterized. However, their sequences are still elusive, and none of these molecules are available for diagnosis. OBJECTIVE: We sought to isolate major allergens from the rabbit Oryctolagus cuniculus and to investigate their importance in sensitized patients. METHODS: Proteins were extracted from rabbit hair, and IgE-reactive proteins were purified by using sequential chromatography. Allergens were characterized by means of N-terminal sequencing and mass spectrometry. IgE reactivity to a new allergen was analyzed in sera of 35 patients sensitized to rabbits in a domestic setting. A model of the crystal structure of the isolated proteins was constructed. RESULTS: A new IgE-reactive allergen, Ory c 3, was identified as rabbit lipophilin. The molecule that belongs to the secretoglobin family is a heterodimer of 18 to 19 kDa composed of 2 polypeptide chains, CL2 and AL. CL2 has a predicted N-linked glycosylation site confirmed by using mass spectrometry. Of the 35 patients with rabbit allergy studied, 27 (77%) had IgE to both the glycosylated and deglycosylated Ory c 3 heterodimer. Allergenicity of Ory c 3 was confirmed by using skin prick tests and the basophil activation assay. Modeling of the structure revealed a marked homology to Fel d 1, the major cat allergen. However, no IgE cross-reactivity was detected between Fel d 1 and Ory c 3. CONCLUSION: The rabbit lipophilin heterodimer AL-CL2 has been identified as a major rabbit allergen. After Fel d 1, Ory c 3 is the second mammalian secretoglobin shown to be a major allergen.
    The Journal of allergy and clinical immunology 06/2013; · 12.05 Impact Factor

Full-text

View
50 Downloads
Available from
May 28, 2014