Seasonal increase in human IgE and IgG4 antisaliva antibodies to Aedes mosquito bites.

Background: Mosquito bite-sensitive subjects frequently have circulating IgE and IgG4 antibodies to Aedes mosquito saliva proteins.

Methods: In the present study we examined the antibody response during a mosquito season in 14 subjects living in Finnish Lapland. Immunoblotting was performed with Aedes communis saliva and the 22- and 36-kD antisaliva antibody bands were analyzed.

Results: The preseason sera showed IgE antibodies to the main saliva antigens in 12, IgG4 antibodies in all 14 and IgG1 antibodies in 12 subjects, and the postseason sera in all but 1 subject. The postseason sera showed significantly more intense IgE (p < 0.05), IgG4 (p < 0.001) and IgG1 (p < 0.01) antibody bands than the preseason sera.

Conclusion: These results show that seasonal exposure to mosquito bites leads to an increased IgE, IgG4 and IgG1 antibody response, a phenomenon similar to that occurring e.g. in pollen allergy.