Virus-like Particle Display of the α‑Gal Epitope for the Diagnostic Assessment of Chagas Disease

• Published in: ACS infectious diseases 2016-12, Vol.2 (12), p.917-922
• Main Authors: Brito, Carlos Ramon Nascimento, McKay, Craig S, Azevedo, Maíra Araújo, Santos, Luíza Costa Brandão, Venuto, Ana Paula, Nunes, Daniela Ferreira, D’Ávila, Daniella Alchaar, Rodrigues da Cunha, Gisele Macedo, Almeida, Igor Correia, Gazzinelli, Ricardo Tostes, Galvão, Lucia Maria Cunha, Chiari, Egler, Sanhueza, Carlos A, Finn, M. G, Marques, Alexandre Ferreira
• Format: Article
• Language: English
• Subjects: Antibodies, Protozoan - analysis; Antibodies, Protozoan - immunology; Antigens, Protozoan - analysis; Antigens, Protozoan - immunology; Chagas Disease - diagnosis; Chagas Disease - parasitology; Enzyme-Linked Immunosorbent Assay; Humans; Trisaccharides - analysis; Trisaccharides - immunology; Trypanosoma cruzi - genetics; Trypanosoma cruzi - immunology; Trypanosoma cruzi - isolation & purification; Viruses - genetics; Viruses - metabolism
• ISSN: 2373-8227; 2373-8227
• DOI: 10.1021/acsinfecdis.6b00114

The α-Gal antigen [Galα­(1,3)­Galβ­(1,4)­GlcNAcα] is an immunodominant epitope displayed by infective trypomastigote forms of Trypanosoma cruzi, the causative agent of Chagas disease. A virus-like particle displaying a high density of α-Gal was found to be a superior reagent for the ELISA-based serological diagnosis of Chagas disease and the assessment of treatment effectiveness. A panel of sera from patients chronically infected with T. cruzi, both untreated and benznidazole-treated, was compared with sera from patients with leishmaniasis and from healthy donors. The nanoparticle-α-Gal construct allowed for perfect discrimination between Chagas patients and the others, avoiding false negative and false positive results obtained with current state-of-the-art reagents. As previously reported with purified α-Gal-containing glycosylphosphatidylinositol-anchored mucins, the current study also showed concentrations of anti-α-Gal IgG to decrease substantially in patients receiving treatment with benznidazole, suggesting that the semiquantitative assessment of serum levels of this highly abundant type of antibody can report on disease status in individual patients.