Z Peng1,2, W W Xu1,3, Y Sham4, H Lam1, D Sun1, L Cheng1, N F Rasic1, Q Guan1,2, A A James5, F E R Simons1,2. 1. Department of Pediatrics and Child Health, University of Manitoba, Winnipeg, MB, Canada. 2. Department of Immunology, University of Manitoba, Winnipeg, MB, Canada. 3. Department of Biochemistry and Medical Genetics, University of Manitoba, Winnipeg, MB, Canada. 4. Center for Drug Design, Academic Health Center, University of Minnesota, Minneapolis, MN, USA. 5. Departments of Microbiology & Molecular Genetics and Molecular Biology & Biochemistry, University of California, Irvine, CA, USA.
Abstract
BACKGROUND: Allergic reactions to mosquito bites are an increasing clinical concern. Due to the lack of availability of mosquito salivary allergens, they are underdiagnosed. Here, we reported a newly cloned mosquito Aedes (Ae.) aegypti salivary allergen. METHODS: A cDNA encoding a 30-kDa Ae. aegypti salivary protein, designated Aed a 3, was isolated from an expression library. The full-length cDNA was cloned into a baculovirus expression vector, and recombinant Aed a 3 (rAed a 3) was expressed, purified, and characterized. Skin prick tests with purified rAed a 3 and Ae. aegypti bite tests were performed in 43 volunteers. Serum rAed a 3-specific IgE levels were measured in 28 volunteers. RESULTS: The primary nucleotide sequence, deduced amino acid sequence, and IgE-binding sites of Aed a 3 were identified. rAed a 3-selected antibodies recognized a 30-kDa Ae. aegypti saliva protein. rAed a 3 bound IgE in mosquito-allergic volunteers and the binding could be inhibited by the addition of natural mosquito extract dose dependently. Immediate skin test reactions to rAed a 3 correlated significantly with mosquito bite-induced reactions. Of the bite test-positive volunteers, 32% had a positive rAed a 3 skin test and 46% had specific IgE. No bite test-negative volunteers reacted to rAed a 3 in either the skin tests or the IgE assays, confirming the specificity of the assay. CONCLUSIONS: Aed a 3 that corresponds to the Aegyptin protein is a major mosquito salivary allergen. Its recombinant form has biological activity and is suitable for use in skin tests and specific IgE assays in mosquito-allergic individuals.
BACKGROUND: Allergic reactions to mosquito bites are an increasing clinical concern. Due to the lack of availability of mosquito salivary allergens, they are underdiagnosed. Here, we reported a newly cloned mosquito Aedes (Ae.) aegypti salivary allergen. METHODS: A cDNA encoding a 30-kDa Ae. aegypti salivary protein, designated Aed a 3, was isolated from an expression library. The full-length cDNA was cloned into a baculovirus expression vector, and recombinant Aed a 3 (rAed a 3) was expressed, purified, and characterized. Skin prick tests with purified rAed a 3 and Ae. aegypti bite tests were performed in 43 volunteers. Serum rAed a 3-specific IgE levels were measured in 28 volunteers. RESULTS: The primary nucleotide sequence, deduced amino acid sequence, and IgE-binding sites of Aed a 3 were identified. rAed a 3-selected antibodies recognized a 30-kDa Ae. aegypti saliva protein. rAed a 3 bound IgE in mosquito-allergic volunteers and the binding could be inhibited by the addition of natural mosquito extract dose dependently. Immediate skin test reactions to rAed a 3 correlated significantly with mosquito bite-induced reactions. Of the bite test-positive volunteers, 32% had a positive rAed a 3 skin test and 46% had specific IgE. No bite test-negative volunteers reacted to rAed a 3 in either the skin tests or the IgE assays, confirming the specificity of the assay. CONCLUSIONS: Aed a 3 that corresponds to the Aegyptin protein is a major mosquito salivary allergen. Its recombinant form has biological activity and is suitable for use in skin tests and specific IgE assays in mosquito-allergic individuals.
Authors: Andrezza Campos Chagas; José Luis Ramirez; Nijole Jasinskiene; Anthony A James; José M C Ribeiro; Osvaldo Marinotti; Eric Calvo Journal: Proc Natl Acad Sci U S A Date: 2014-04-28 Impact factor: 11.205
Authors: Andrew F van den Hurk; Sonja Hall-Mendelin; Alyssa T Pyke; Francesca D Frentiu; Kate McElroy; Andrew Day; Stephen Higgs; Scott L O'Neill Journal: PLoS Negl Trop Dis Date: 2012-11-01
Authors: Michele S Barros; Eliane Gomes; Daniele I Gueroni; Anderson D Ramos; Luciana Mirotti; Esther Florsheim; Bruna Bizzarro; Ciro N R Lino; Ceres Maciel; Adriana Lino-Dos-Santos-Franco; Wothan Tavares-de-Lima; Margareth L Capurro; Momtchilo Russo; Anderson Sá-Nunes Journal: PLoS One Date: 2016-05-20 Impact factor: 3.240