[Detection of an antigen related to systemic Candida infection using a monoclonal antibody conjugated to colloidal gold]

Abstract

Previously we showed it was possible to detect antigenemia associated with systemic candidiasis using an anti-C. albicans monoclonal antibody conjugated to colloidal gold. The technique being used, known as Immuno-Gold-Silver staining (IGSS), is applied to serum dots on cellulose nitrate. It is very simple in practice, the results of the reaction being visible with the naked eye. The diagnostic value of IGSS has been compared, on the one hand, with that of the anti-Candida antibody detection by co-counterimmunoelectrophoresis and indirect immunofluorescence, on the other hand with that of the antigen detection using the Cand-Tec commercial test. The specificity and sensitivity of these methods have been established in relation to sera of 79 subjects shared out into 4 groups: sound-subjects, patients having developed systemic candidiasis following surgery, leukemic patients apparently uninfected with Candida and leukemic patients suffering from systemic candidiasis. The IGSS which is slightly less specific than the Cand Tec makes it possible to diagnose a much greater number of infections. Selected bioclinical observations show that there exists complementarity between the detection tests of antibodies and those of antigens and that it is possible to attribute a prognosis value to antigenemia detected with the IGSS dot method.