Immunoblot analysis of allergens in crude mosquito extracts

Whole body extracts of Aedes albopictus (AAL), Aedes aegypti (AAE) and Culex quequectates (CQU) were subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis. At least 28, 37 and 26 polypeptides, molecular weights (MWs) ranging from 16 to 120 kilodaltons (kD), respectively, were visible following Commassie brilliant blue staining. Sera of two mosquito-sensitive patients were examined for IgE binding to mosquito proteins by immunoblotting. Sera from both patients revealed IgE binding to 52- and 56-kD proteins of AAL. In addition, serum from patient B also bound 48 kD of AAL and did not bind any components of AAE and CQU. Serum from patient A also bound 32 and 58 kD of AAE, and bound only 58 kD of CQU. Sera from 2 control subjects, nonatopic and mosquito-negative atopic, did not bind specific human IgE to any proteins, as demonstrated by negative autoradiographs. Immunoblot analysis showed unique individual IgE-binding patterns and suggested that both genus- and species-specific mosquito allergens exist.