Christine AznarPablo Lopez‐BergamiSilvia BrandarizChristine MariettePascale LiégeardMaria do Carmo de Deus AlvesErika Luna BarreiroRoxana CarrascoSonia LafonDan Kaplan2026-03-222026-03-22199510.1111/j.1574-695x.1995.tb00197.xhttps://doi.org/10.1111/j.1574-695x.1995.tb00197.xhttps://andeanlibrary.org/handle/123456789/48153Citaciones: 35Infection with Trypanosoma cruzi develops in three phases: acute, indeterminate or asymptomatic, and chronic phase (with cardiac or digestive manifestations). Moreover, transmission may occur from infected mothers to newborn, the so-called congenital form. In the present study, humoral responses against T. cruzi total extract and against the 13 amino acid peptide named R-13 derived from the parasite ribosomal P protein, previously described as a possible marker of chronic Chagas heart disease, were determined pateints and in blood bank donors from endemic areas. While in sera from acute phase, only IgM anti-T.cruzi response was observed, both IgM and IgG anti-T. cruzi antibodies were detected in sera from congenitally infected newborns. The percentage of positive response in sera from blood bank donors was relatively high in endemic regions. Antibodies against the R-13 peptide were present in a large proportion of cardiac chagasic patients but were totally lacking in patients with digestive form of Chagas disease. Furthermore, anti-R-13 positive responses were detected in congenitally infected newborns.enTrypanosoma cruziBiologyChagas diseaseAntibodyVirologyMicrobiologyTrypanosomiasisImmunologyarticle