INTRODUCTION AND OBJETIVES

1. 106 Chagas’ disease diagnosis: a rapid lateral chromatographic assay using recombinant proteins of Trypanosomacruzi 1Andrea Racca, 2Sebastian Marechal, 2Dominique Zeluz, 2Thierry Paper, 1Ivan Marcipar 1Laboratorio de Tecnología Inmunológica. FBCB. UNL. 2Biosynex Estrasburgo, Francia INTRODUCTION AND OBJETIVES Chagas’ disease is an infection caused by the parasite Trypanosomacruzi, mainly occurring in Latin American countries where the parasite vector bug, Triatomainfestans, is widespread. The aim of this work was to evaluate a rapid immunochromatographic assay in development for detection of antibody to T. cruzi: ImmunoquickChagas test (Biosynex, France). This rapid test performance was compared with OPERON Chagas Test, an immunochromatographic assay commercially available. MATERIALS AND METHODS We evaluated serum samples from T. cruzi-infected patients (n =100) which were obtained from the Regional Hospital of Reconquista (Santa Fe, Argentina). Chagas’ disease-negative serum samples without other reactivity (n =102) were obtained from donors from the same hospital. Conventional assays, commercial ELISA and IHA from Wiener Lab (Argentina), were used for diagnostic classification and served for comparison for both rapid tests. Biosynex´simmunochromatographic is composed of an absorbent pad, a nitrocellulose membrane striped with a control line reagent, a test line reagent with chimeric recombinant T. cruziantigens and a conjugate pad that contains dried detector reagent. The assay uses 10µl of non diluted samples and a drop rof buffer (Figure 1 and 2). Results are read after 15 min. Figure 1 Figure 2 Negative tests display one band corresponding to interassay control line Positive results display an extra band corresponding to the specific recombinant T. cruziantigen. Figure 3: Four negative test results are shown. Figure 5: Four weak positive test results are shown. Figure 4: Four positive test results are shown. Table 1: Performance of two rapid tests RESULTS CONCLUSIONS Reithinger, R. et al. Rapid Detection of Trypanosomacruziin Human Serum by Use of an Immunochromatographic Dipstick Test. J ClinMicrobiol. 2010 Aug;48(8):3003-7 Barfield, C.A. et al. A Highly Sensitive Rapid Diagnostic Test for C hagas Disease That Utilizes a Recombinant Trypanosomacruzi Antigen. IEEE TransBiomedEng. 2011 Mar;58(3):814-7. * Convencional serologywasperformedwith a lysate-based ELISA and IHA. Positive and negativespecimenswereconcordantforbothassays. The high sensitivity obtained with ImmunoquickChagas Test in this preliminary evaluation, indicates that the Biosynex assay has great potential as a new rapid assay for screening purposes.