[The diagnosis of chronic Chagas disease using recombinant antigens of Trypanosoma cruzi]

A panel of eight recombinant Trypanosoma cruzi antigens was used to study the IgG reactivity of sera proceeding from 151 patients with chronic Chagas disease. These samples were reactive against T Cruzi epimastigotes by immunofluorescence and enzyme linked assays. A dot blot assay was performed to evaluate the reactivity against recombinant clones 1, 2, 13, 26, 30, 36, 54 and SAPA (Shed Acute Phase Antigen). Ninety six percent of samples reacted against one or more of these antigens. The most frequently recognized proteins were clones 1, 2, 13, 36 and 26 with 90, 89, 76, 71 and 66 percent of reactivity respectively. Less than 50% of sera reacted against clones 30, 54 and SAPA. Sera from symptomatic patients had a significantly higher frequency of reactivity against clone SAPA than those from asymptomatic patients. This difference suggests that a high reactivity against clone SAPA may be related to acute infections and symptoms. No significant relationship could be established between specific recombinant clone recognitions and particular clinical forms of the disease (cardiological or digestive). It is concluded that these recombinant proteins may become a good tool for the evaluation of the immune response of patients infected with T. cruzi.