Interaction of GP90 surface glycoprotein of Trypanosoma cruzi to mammalian cells: identification of binding sites and epitopes in the carboxy-terminal region of GP90

• Grant number: 11/21630-7
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: March 01, 2012
• End date: February 28, 2013
• Field of knowledge: Biological Sciences - Parasitology - Protozoology of Parasites
• Principal Investigator: José Franco da Silveira Filho
• Grantee: Flávia Eichemberger Rius
• Host Institution: Escola Paulista de Medicina (EPM). Universidade Federal de São Paulo (UNIFESP). Campus São Paulo. São Paulo , SP, Brazil

Abstract

The metacyclic trypomastigotes of Trypanosoma cruzi express two major surface glycoproteins called GP90 and GP82 that bind to mammalian cells through specific host receptors. The expression of GP90 protein correlates inversely with the invasive capacity of Trypanosoma cruzi, while the GP82 promotes the penetration of metacyclic forms into host mammalian cells. It has been suggested that the presence of high levels of GP90 on the parasite surface could impair the binding of GP82 to target cells, resulting in down regulation of host cell invasion. We propose to identify the sequences in the carboxy-terminal region of GP90-related to cell adhesion using monoclonal antibodies, recombinant proteins and assays for adhesion and penetration of metacyclic forms into mammalian cell. It will be assessed the inhibitory capacity of different segments from GP90-terminal end (expressed as recombinant proteins) in the adhesion of metacyclic forms to mammalian cells. This is a first step to understanding the role of GP90 in the interaction of the parasite with its vertebrate host.