INHIBITION OF MOSQUITO SALIVARY-GLAND APYRASE ACTIVITY BY ANTIBODIES PRODUCED IN MICE IMMUNIZED BY BITES OF ANOPHELES-STEPHENSI MOSQUITOS

Mice (BALB/c) were immunized to mosquito saliva by repeated bites of A nopheles stephensi mosquitoes. Studies were conducted on the ability o f these mice to develop antibodies against the apyrase component of th e saliva. By means of immunoprecipitation procedures and Western blot analysis, we demonstrated the presence of anti-apyrase antibodies to t he mosquito saliva. Furthermore, these antibodies were able to inhibit apyrase activity. Serum titers of 1:20 were able to inhibit approxima tely 90% of salivary gland apyrase activity, while titers of 1:160 ret ained the ability to inhibit more than 50% of apyrase activity. parall el inhibition assays with immunoglobulin G (IgG) from immunized versus nonimmunized mice showed that the inhibitory activity of serum from i mmunized mice could be accounted for by its Ige component. Mosquito sa livary gland apyrase has previously been shown to facilitate mosquito feeding by inhibiting aggregation of platelets at the mosquito bite si te. However, our studies have shown that mosquitoes feeding on immuniz ed mice had no deficiency in probing these mice for a blood meal, even in the face of high titers of anti-apyrase antibodies.