RESUMO
Diagnosis of tuberculosis a problem, specially in the regions harboring an abundance of both pathogenic and non-pathogenic mycobacteria. This study was undertaken to assess in such a situation the predictive value of proliferative T cell response to a peptide epitope ('38G') of the 38 kDa membrane protein of Mycobacterium tuberculosis. 3[H]-thymidine incorporation assays were done with peripheral blood mononuclear cells of tuberculoid leprosy and pulmonary tuberculosis patients. The donors were also classified as PPD responders (Stimulation Index, SI> 3) or non-responders (SI 3 in 54 per cent subjects) and non-responders (SI > 3 in 29 per cent subjects). However, it did not differentiate between leprosy and tuberculosis. The study supports use of liposomes as adjuvant vehicles for antigenic peptides designed to activate human T cells.
Assuntos
Humanos , Antígenos de Bactérias/administração & dosagem , Antígenos de Bactérias/genética , Antígenos de Bactérias/química , Ativação Linfocitária , Dados de Sequência Molecular , Diagnóstico Diferencial , Epitopos/administração & dosagem , Epitopos/genética , Epitopos/química , Hanseníase Tuberculoide/diagnóstico , Hanseníase Tuberculoide/imunologia , Linfócitos T/imunologia , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/imunologia , Mycobacterium tuberculosis/química , Sequência de Aminoácidos , Teste Tuberculínico , Tuberculose Pulmonar/diagnóstico , Tuberculose Pulmonar/imunologia , Lipossomos , Peso MolecularAssuntos
Antígenos de Bactérias/imunologia , Antígenos de Bactérias/isolamento & purificação , Ativação Linfocitária , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Fito-Hemaglutininas/farmacologia , Hanseníase Tuberculoide/imunologia , Linfócitos T/imunologia , Mycobacterium leprae/enzimologia , Peso Molecular , Proteínas de Bactérias/imunologia , Proteínas de Bactérias/isolamento & purificação , Sequência de Aminoácidos , Superóxido Dismutase/imunologia , Superóxido Dismutase/isolamento & purificação , Vacinas BacterianasRESUMO
Two of the Mycobacterium leprae-specific assays--a serum antibody competition (for an epitope on 35-kDa protein) test (SACT) and an enzyme-linked immunosorbent assay (ELISA) for the disaccharide epitope of phenolic glycolipid-I (PGDS)--were comparatively evaluated as tools for monitoring chemotherapy in 125 lepromatous leprosy (LL/BL) patients. An adaptation of the SACT from a radioimmunoassay (RIA) to an ELISA procedure is also described. A moderate but statistically significant correlation was observed between the assays, although SACT appeared to be the more sensitive of the two. Levels of antibodies correlated better with the bacterial index (BI) than with the duration of treatment. However, wide individual variations in antibody levels (for a specific duration of treatment or BI) were seen in treated as well as untreated patients. Anti-PGDS antibody response of the IgG type was poorer than that of the IgM type and, apparently, it did not have a bearing on either treatment duration or the BI. Further studies will be needed to clarify whether the treated patients showing a negative (or low) BI and high antibody levels were harboring hidden foci of active infection, and whether treatment could safely be terminated in patients showing low values for both BI and antibody