RESUMO
Here we describe the characterization of a Trypanosoma cruzi DNA sequence (clone A13) that codes for a polypeptide recognized by IgM and IgG antibodies from sera of acute and congenital chagasic patients. Antibodies to A13 antigen are also detected in the sera of chronic patients with different clinical forms of Chagas' disease, but not in sera of patients with leishmaniasis or other parasitic diseases. The antigenic determinants encoded by clone A13 are found in amastigotes and trypomastigotes of several T. cruzi strains, but not in the noninfective epimastigotes. The DNA sequence of the recombinant clone reveals one open reading frame encoding 251 amino acids without tandemly repeated sequences. Our data suggest that the A13 antigen may be useful for the development of serodiagnostic procedures.
Assuntos
Antígenos de Protozoários/genética , Doença de Chagas/imunologia , DNA de Protozoário/genética , Trypanosoma cruzi/imunologia , Doença Aguda , Sequência de Aminoácidos , Animais , Antígenos de Protozoários/imunologia , Sequência de Bases , Doença de Chagas/diagnóstico , Doença Crônica , Clonagem Molecular , DNA de Protozoário/isolamento & purificação , Epitopos/genética , Epitopos/imunologia , Regulação da Expressão Gênica , Humanos , Imunoglobulina G/imunologia , Imunoglobulina M/imunologia , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Trypanosoma cruzi/genéticaAssuntos
Antígenos de Protozoários , Doença de Chagas/imunologia , Escherichia coli/imunologia , Trypanosoma cruzi/imunologia , Animais , Anticorpos Antiprotozoários/análise , Anticorpos Antiprotozoários/imunologia , Antígenos de Protozoários/imunologia , Humanos , Proteínas Recombinantes/imunologia , Sensibilidade e EspecificidadeRESUMO
A genomic clone expressing a Trypanosoma cruzi antigen in Escherichia coli was identified using human chagasic sera. Chagasic antibodies affinity purified on extracts of this clone recognized a high-molecular-weight protein expressed in all developmental stages of the parasite life cycle, as well as in various T. cruzi strains. The antigen is associated with the cytoskeleton of the parasite and localizes along the attachment region between the flagellum and the cell body. Antibodies to the recombinant antigen were detected in the sera of 115 chagasic patients from different endemic regions, but not in sera of patients with leishmaniasis, T. rangeli infection, or other parasitic diseases. Our data suggest that the presence of antibodies to this antigen may be specifically associated with Chagas' disease.
Assuntos
Antígenos de Protozoários/genética , Doença de Chagas/imunologia , Trypanosoma cruzi/imunologia , Animais , Northern Blotting , Southern Blotting , Western Blotting , Clonagem Molecular , Citoesqueleto/imunologia , DNA/genética , Epitopos/imunologia , Escherichia coli/genética , Imunofluorescência , Expressão Gênica , Humanos , Soros Imunes/imunologia , Trypanosoma cruzi/genética , Trypanosoma cruzi/ultraestruturaRESUMO
The number of nerve cells in the myenteric plexus of a freshwater teleost (Pimelodus maculatus) was obtained with the aid of statistical methods. 1. The density of neurons/cm2 was the following: 91,142 in the duodenum; 93,133 in the ileum and 82,857 in the rectum. These 3 portions have not showed statistically significant differences. 2. The mean surface area of the intestine being 48 cm2, the total number of neurons in myenteric plexus of the duodenum, ileum and rectum was calculated to be 4,274,112.
