Impact of cross-reactive carbohydrate determinants on wood dust sensitization.

BACKGROUND

Occupational wood dust exposure can induce allergy and may be one cause of respiratory health problems among woodworkers.

OBJECTIVE

The objective was to determine the prevalence and quantitative level of specific immunoglobulin E (sIgE) to beech and pine wood in exposed workers. Wood sensitization was specified with regard to cross-reactivity and was correlated to the reported symptoms.

METHODS

Danish workers (n=701) were investigated for sIgE to beech and pine. Wood samples from workplaces were analysed and coupled to ImmunoCAPs. Workers sensitized to wood were tested for cross-reactive carbohydrate determinants (CCDs) and environmental allergens. IgE binding was specified for glycogenic vs. proteinogenic epitopes by inhibition tests.

RESULTS

The prevalence of wood sensitization among all workers was 3.7%. There was no association between sensitization prevalence or sIgE concentrations and self-reported allergic symptoms. Beech- and pine-sensitized workers showed a high prevalence of CCD sensitization (73%). However, workers with a single sensitization to wood had no sIgE to CCDs. Specifying IgE epitopes demonstrated that sera of workers reporting allergic symptoms recognized proteinogenic IgE-epitopes on wood allergens, whereas workers without allergic symptoms had primarily sIgE-epitopes to glycogenic structures. Although 96% of the wood-sensitized workers were atopic, no significant correlation was found between wood sensitization and sIgE to beech and birch pollen, but an association was found between sIgE against CCDs and pine pollen.

CONCLUSION

Sensitization prevalence to beech and pine wood measured by tailored ImmunoCAPs was not correlated to allergic symptoms. We recommend the application of CCD tools to assess the relevance of individual wood sensitization.