RESUMO
A 24-kDa recombinant protein from Trypanosoma cruzi (rTc24) was evaluated by enzyme-linked immunosorbent assay (ELISA) and Western blot (immunoblot) tests to identify treated chagasic patients considered parasitologically cured on the basis of persistently negative tests of hemocultures and lytic antibodies. Some of these patients were termed dissociated because their sera, although negative by the complement-mediated lysis test, were positive by conventional serology. The negative lysis test indicates the absence of active infection after specific treatment, but this assay requires live and infectious parasites and cannot be used easily in a laboratory routine. Here we tested rTc24 by ELISA and Western blotting as an alternative for the complement-mediated lysis test. For the group of patients with active infection despite the treatment (uncured patients), all the sera tested recognized rTc24 in both tests. For the dissociated patients, approximately 80% of the sera did not react with rTc24 in the ELISA or in Western blots, in agreement with the negative complement-mediated lysis tests. Thus, the 24-kDa T. cruzi recombinant antigen, when used for initial trials to evaluate cure of chagasic patients submitted to specific treatment, will allow the identification of most, but not all, cases.
Assuntos
Doença de Chagas/tratamento farmacológico , Doença de Chagas/imunologia , Proteínas de Protozoários/imunologia , Trypanosoma cruzi/imunologia , Animais , Anticorpos Antiprotozoários/sangue , Antígenos de Protozoários/química , Antígenos de Protozoários/genética , Western Blotting , Doença de Chagas/parasitologia , Doença Crônica , Ensaio de Imunoadsorção Enzimática , Estudos de Avaliação como Assunto , Humanos , Peso Molecular , Proteínas de Protozoários/química , Proteínas de Protozoários/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Tripanossomicidas/uso terapêutico , Trypanosoma cruzi/genéticaRESUMO
The prevalence of hemoglobinopathies was determined in the black race located in two distinct geographical areas in Ecuador; in the coastal province of Esmeraldas, particularly the Santiago basin (Rio Cayapas and Rio Onzoles) and in the province of Imbabura, particularly in the intermoutain valley, Valle de Chota. A total of 2038 blood samples were analyzed, 1734 in Esmeraldas and 304 in Inbabura, of which 23.2% (473 individuals) were found to be carriers of abnormal hemoglobins, 25.4% (441) in Esmeraldas and 10.5% (32) in Imbabura. The abnormal hemoglobins found in Esmeraldas were Hb AS (19.2%), Hb AC (5.0%), Hb SS (0.6%) and Hb SC (0.5%) while in Imbabura only Hb AS (9.5%) and Hb AC (0.9%) were found. The factors that could influence the difference in prevalence found in the two geographical areas are discussed.