Peptide epitopes of Trypanosoma cruzi have been identified through expression cloning. A
tripeptide (2/D/E) containing three epitopes (TcD, TcE, PEP-2) was used in ELISA to detect
antibodies to T. cruzi in 239 of 240 consensus-positive sera and 41 of 42 sera confirmed
positive by radioimmunoprecipitation assay. The 1 discrepant consensus-positive serum
was used to expression-clone a novel gene that contained a repeat sequence. A peptide
corresponding to this sequence, TcLo1. 2, was specific for T. cruzi. This antigen detected the …

A tetrapeptide and a recombinant protein, each representing 4 immunodominant epitopes of
Trypanosoma cruzi, were tested by use of ELISA for the detection of serum antibodies. Sera
from individuals with Chagas' disease, including persons untreated and successfully or
unsuccessfully treated, were tested. These assays detected antibody in 100% of the
parasitemias. The antibody reactivity decreased based on the success of treatment. Higher
sensitivity was observed for tetrapeptide/recombinant protein assays than for lysate-based …