The natural history of Apis-specific IgG and IgG4 in beekeepers.

BACKGROUND

Most published studies on changes of specific IgG or its subclasses as a response to stimuli by allergens have been performed on patients under immunotherapy. There are few reports analysing the response to immunoglobulins in patients exposed to allergens in their natural habitats.

OBJECTIVE

The aim of this work was to discover the natural history of Apis specific IgG (IgG-ap) and IgG4 (IgG4-ap) levels in beekeepers from the Canary Islands.

METHODS

We studied 242 beekeepers (Bks). We used a questionnaire and measured total IgE and seric Apis specific IgE (IgE-ap), IgG-ap and IgG4-ap against Apis mellifera venom.

RESULTS

All Bks had IgG-ap and IgG4-ap. IgE-ap was positive in 160 Bks (65.6%), but only 92 (37.6%) Bks were considered sensitized. IgG-ap and IgG4-ap showed significant correlation (r = 0.84); IgE did not correlate with IgG-ap or IgG4-ap. There was no seasonal variation in IgG-ap or IgG4-ap. The group of sensitized Bks had significantly lower IgG-ap and IgG4-ap levels (P < 0.05). The groups with longer beekeeping activity showed significantly higher levels of IgG-ap and IgG4-ap (P < 0.001). Bks with locals reactions had significantly higher IgG-ap and IgG4-ap than Bks who reported systemic reactions (P < 0.05).

CONCLUSION

Our study showed that IgG-ap and IgG4-ap appear to increase in Bks, either according to their beekeeping experience or in subjects with local reactions after bee stings.