Using the immunoblot technique, we analyzed the quality and quantity of IgG, IgG4, and IgE specific to mosquito salivary gland (hereafter abbreviate as SG) components of Aedes albopictus in the sera of volunteers with common reactions and of 3 patients with severe reactions. In the volunteers with delayed reactions only or with both delayed and immediate reactions, IgG against SG components of A. albopictus formed several faint or moderately stained bands. Those with immediate reactions showed several intense bands and many other weak bands. In volunteers, who had been bitten by Aedes sp. frequently but had no skin reaction, and in severe cases, many intense IgG bands were observed. IgG4 bound to SG components were found in the sera of the common reaction group at the levels of 24 and 48 kD, but, in one severe case, no bands were observed, although the total IgG was very high. IgE levels specific to SG components were much higher in severe cases than in the volunteers. These results indicate that high titers of specific IgG and IgE and lack of IgG4 for particular components of SG may lead to severe allergic reactions in severe cases. Immunoblotting analysis of the antibodies also verified the possibility of developing in vitro tests to identify causative species of the mosquito for severe cases.

No abstract