Biochemical Characterization of an In-House Coccidioides Antigen: Perspectives for the Immunodiagnosis of Coccidioidomycosis

Abstract

The objective of this study was to evaluate the reactivity of an in-house antigen, extracted from a strain of C. posadasii isolated in northeastern Brazil, by radial immunodiffusion and Western blotting, as well as to establish its biochemical characterization. the protein antigen was initially extracted with the use of solid ammonium sulfate and characterized by 1-D electrophoresis. Subsequently, it was tested by means of double radial immunodiffusion and Western blotting. A positive reaction was observed against the antigen by both immunodiagnostic techniques tested on sera from patients suffering from coccidioidomycosis. Besides this, two immunoreactive protein bands were observed and were revealed to be a beta-glucosidase and a glutamine synthetase after sequencing of the respective N-terminal regions. Our in-house Coccidioides antigen can be promising as a quick and low-cost diagnostic tool without the risk of direct manipulation of the microorganism.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordination for the Improvement of Higher Education PersonnelUniv Fed Ceara, Specialized Med Mycol Ctr, Sch Med, BR-60430270 Fortaleza, Ceara, BrazilUniv Estadual Ceara, Postgrad Program Vet Sci, Sch Vet Med, BR-60740000 Fortaleza, Ceara, BrazilUniv Fed Ceara, Dept Biochem & Mol Biol, BR-60455760 Fortaleza, Ceara, BrazilUniversidade Federal de São Paulo, Dept Microbiol Immunol & Parasitol, BR-04021001 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Microbiol Immunol & Parasitol, BR-04021001 São Paulo, BrazilCNPq: 302574/2009-3CNPq: 306637/2010-3Coordination for the Improvement of Higher Education Personnel: CAPES/PNPD2103/2009Web of Scienc