THE CLONED C-TERMINAL REGION OF A TRYPANOSOMA-CRUZI P-RIBOSOMAL PROTEIN HARBORS 2 ANTIGENIC DETERMINANTS

A DNA strategy was designed to characterize the antigenic site(s) within a γgt11 cloned 35-amino-acid antigenic peptide, identified with antibodies from patients with chronic Chagas' heart disease (cChHD) and systematic lupus erythematosus (SLE) as the C-terminal portion of a Trypanosoma cruzi P ribosomal protein. The 198-bp cDNA insert was digested with AluI, resulting in two DNA segments that were recloned in γgt11. To identify specific antigenic determinants, the recombinant phage and the purified recombinant antigens were probed with sera from clinically characterized subjects. Chronic ChHD and SLE sera defined a linear epitope common to both diseases within the 15 C-terminal residues of the parasite P ribosomal protein. It is also shown that the cloned 35-amino-acid peptide contained an antigenic site unique to cChHD. © 1990.