Immunoblot evaluation of the T. cruzi antibodies reactivity with antigenic molecules of insect (Leptomonas seymouri) and plant (Phytomonas serpens) trypanosomatids

• Grant number: 18/19367-5
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: February 01, 2019
• End date: December 31, 2020
• Field of knowledge: Biological Sciences - Parasitology - Protozoology of Parasites
• Principal Investigator: Norival Kesper Junior
• Grantee: Rafael Avila Rocci
• Host Institution: Faculdade de Medicina (FM). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Trypanosomatids of insects (Crithidia, Leptomonas, Herpetomonas, Blastocrithidia, Angomonas, e Strigomonas, and plants (Phytomonas) that are not pathogenic to humans play a prominent role in scientific research. They may share or contain molecular repertoires with recognized homology in human pathogenic species, including molecules with importance in virulence and host pathogen interaction. These facts, together with the phylogenetic proximity between the different genera, justifies the observations, since 1960s, on the phenomenon of cross immunoreactivity among members of the family Trypanosomatidae. Promising results were obtained by our group in the study of immunoreactive epitopes present in insect and plant trypanosomatids as alternative antigenic sources for the immunodiagnosis of T. cruzi and Leishmania spp. In this current proposal, we intend to continue the critical analysis of antigenic epitopes identified by anti-T. cruzi antibodies present in non-pathogenic trypanosomatids, Leptomonas seymouri and Phytomonas serpens. Our objective is to identify and further evaluate molecules, which can react specifically with sera from chagasic patients in the acute and chronic phases of the disease, including those with low reactivity for conventional serology, using immunoblotting. The TESA-Blot test, with high sensitivity and specificity in the immunodiagnosis of Chagas Disease, will be used in parallel as a parameter of comparison. Understanding the antigenic characteristics of these Trypanosomatids is relevant, as it will probably allow the probe of alternative antigenic sources to improve the immunodiagnostic tests applied to Chagas' disease. It is significant that L. seymouri and P. serpens grow easily and rapidly in culture medium and present low risk to the technical manipulator.