[Solid-phase radioimmunoassay for the study of the humoral response to Trypanosoma cruzi]

A solid-phase micro-radioimmunoassay (RIE-S) test was adapted fore the study of the humoral immune response induced by Trypanosoma cruzi infection. The solid phase, consisting of disposable polypropylene tubes, was sensitized by absorption of T. cruzi antigen. The procedure was performed by sequential adding to the solid-phase, the human serum under study and 131I anti-human immunoglobulin. Then, the specific label binding was estimated. Several factors which influence the test were studied. The RIE-S results correlated well with those obtained by complement-fixation, passive hemagglutination and immunofluorescence tests. Since it is a relatively simple and sensitive procedure, it seems available for screening studies, Besides, it also allows to know the class and molecular specificity of the antibody detected.