A novel peptide-based sensor platform for detection of anti-Toxoplasma gondii immunoglobulins

Publication date: Available online 17 July 2019Source: Journal of Pharmaceutical and Biomedical AnalysisAuthor(s): Lívia M. Alves, Heber L.S. Barros, José M.R. Flauzino, Pedro H.G. Guedes, Janser M. Pereira, Ricardo Toshio Fujiwara, Tiago W.P. Mineo, José R. Mineo, Ronaldo J. de Oliveira, João M. Madurro, Ana G.Brito-MadurroAbstractToxoplasma gondii is an intracellular protozoan parasite responsible for toxoplasmosis, which affects humans and animals. Serologic detection of anti-T. gondii immunoglobulins plays a crucial role in the clinical diagnosis of toxoplasmosis. In this work, a novel electrochemical immunosensor for detecting anti-T. gondii immunoglobulins is reported, based on immobilization of an in silico predicted peptide (PepB3), obtained from membrane protein of T. gondii, on the graphite electrode modified with poly(3-hydroxybenzoic acid). Indirect ELISA confirmed infection and binding specificity of peptide PepB3. Molecular modeling and simulations show this peptide binds to the T. gondii human Fab antibody in the surface antigen 1 (SAG1) binding site, remaining a stable complex during the molecular dynamic simulations, especially by hydrogen bonds and hydrophobic interactions. This electrochemical immunosensor was able to discriminate different periods of infection, using infected mouse serum samples, showing selectivity and discriminating infected and uninfected mouse serum.
Source: Journal of Pharmaceutical and Biomedical Analysis - Category: Drugs & Pharmacology Source Type: research