Immunological selection for Leishmania (Viannia) braziliensis antigens.

Comparative ELISA and selective immunoblotting procedures were used in attempts to identify differential serological indicators of infection with the Leishmania (Viannia) braziliensis complex, infection with the L. braziliensis species, and therapeutic cure of localized or mucocutaneous leishmaniasis (LCL or MCL). Although mean ELISA absorbance values were significantly higher for MCL sera than for LCL sera, absorbance could not be used as a reliable indicator of the clinical form of disease. Immunoblotting profiles were similar with sera from MCL and LCL. Pre-adsorption with heterologous trypanosomatid antigens indicated that recognition of antigens of about 56, 60, 66, 72, 88 and 110 kDa might be specific to the subgenus Viannia. In two-colour, sequential, dual ELISA-based immunoblotting, no antigens recognized only by sera from MCL patients were detected. After glucantime therapy, immunoblotting profiles with LCL sera were reduced both in intensity and in the range of antigens detected; a 104-kDa antigen was newly detected with post-treatment LCL sera. Overall, the results show the value of differential immunological detection strategies and support the close relationship between species of the subgenus Viannia but fail to indicate a prognostic antigen for MCL.

Molecular and biologic characterization of Leishmania parasites implicated in an epidemic outbreak in northwestern Argentina.

Leishmania (Viannia) braziliensis and its variants were implicated in the epidemic outbreak of mucocutaneous leishmaniasis that occurred in Salta, northwestern Argentina, in 1985. A total of 24 suspected, untreated cases were evaluated clinically and parasitologically. Four of five stable isolates were consistent with the reference strain of L. (V.) braziliensis as determined by monoclonal antibodies and indirect immunofluorescence or radioimmunobinding assays. Zymodeme analysis in agarose gels showed a close relationship with L. (V.) guyanensis and L. (V.) panamensis. All zymograms obtained with polyacrylamide gels belonged to the subgenus Viannia; the patterns were different from, but very closely related to, the reference strains of L. (V.) braziliensis as determined by dendrogram analysis. Hamsters infected with two isolates showed a pattern consistent with L. (V.) braziliensis. The pattern of development in the gut of Lutzomyia longipalpis was consistent with members of Viannia.

Phylogenetic taxonomy of Leishmania (Viannia) braziliensis based on isoenzymatic study of 137 isolates.

Biochemical characterization of 137 Leishmania braziliensis isolates from South and Central America, and from selected endemic foci in Bolivia, Brazil and Colombia, performed by isoenzymatic electrophoresis using 10 enzymatic systems, showed a high enzymatic polymorphism (44 zymodemes obtained) based on the variation of a small number of enzymes. Cladistic analysis showed close links between the zymodemes within the L. braziliensis s.s. cluster. The position of 2 Colombian zymodemes obtained (MON*204 and MON*205) justify the inclusion of L. peruviana within the L. braziliensis cluster.

Human cutaneous leishmaniasis caused by Leishmania (Viannia) braziliensis in Santiago del Estero, Argentina: identification of parasites by monoclonal antibodies and isoenzymes

Estudos de diagnostico, caracterizacao parasitaria e identificacao foram conduzidos em pacientes humanos com lesoes cutaneas de leishmaniose na Provincia de Santiago del Estero, no norte da Argentina. Os procedimentos de diagnostico foram: biopsias de lesoes para utilizacao em esfregacos e inoculacao em hamster; aspiracao (com agulha) de ulceras, para cultura "in vitro". As tecnicas a IFAT-IgG e o teste intradermico de Montenegro. Oito cepas de parasitas foram isoladas, sendo estas obtidas de pacientes com lesoes ativas...

Dissemination of Leishmania (Viannia) braziliensis.

Destructive human mucocutaneous leishmaniasis may appear many years after the primary cutaneous infection with Leishmania (Viannia) braziliensis. Hamsters (Mesocricetus auratus) were infected with metacyclic L. braziliensis promastigotes. It was found that secondary metastatic visceral lesions could arise from a primary cutaneous lesion, or secondary cutaneous lesions from a primary visceral lesion. Parasites in the viscera were shown to be viable, multiplying and capable of metastasis to either secondary visceral or cutaneous sites. The finding of an early metastasis in the wall of a small cutaneous vessel indicates that dissemination can occur by the haematogenous route. Slow growing organisms in viscera may thus be a source for late metastasis to mucocutaneous sites or for systemic relapse after immunosuppression.

Marmosets in New World leishmaniasis research

En leismaniasis, la búsqueda de un modelo animal experimental apropiado es muy recomendable, especialmente en las investigaciones de laboratorio con la especie Leishmania (Viannia) braziliensis, L. (V) b. Diversas especies de primates neotropicales han sido usados con frecuencia como huéspedes experimentales de Leishmania. Este artículo descrive aspectos de la interacción del parásito, L. (V) b. y los micos "estrella" o "titles" (primates, Callithricidae) como huéspedes experimentales y resume datos sobre la biologia del parasitismo en este modelo primate. Se comentan sumariamente los resultados de estudios recientes sobre infecciones primarias con varias cepas de L. (V) b y sobre la evolución del parasitismo, los patrones clínicos resultantes y los experimentos de immunoprotección. Se discute la relevancia de los hallazgos en los experimentos de reinfección homóloga en el desarrollo de una vacuna para leishmaniasis

Marmosets in New World leishmaniasis research

En leismaniasis, la búsqueda de un modelo animal experimental apropiado es muy recomendable, especialmente en las investigaciones de laboratorio con la especie Leishmania (Viannia) braziliensis, L. (V) b. Diversas especies de primates neotropicales han sido usados con frecuencia como huéspedes experimentales de Leishmania. Este artículo descrive aspectos de la interacción del parásito, L. (V) b. y los micos "estrella" o "titles" (primates, Callithricidae) como huéspedes experimentales y resume datos sobre la biologia del parasitismo en este modelo primate. Se comentan sumariamente los resultados de estudios recientes sobre infecciones primarias con varias cepas de L. (V) b y sobre la evolución del parasitismo, los patrones clínicos resultantes y los experimentos de immunoprotección. Se discute la relevancia de los hallazgos en los experimentos de reinfección homóloga en el desarrollo de una vacuna para leishmaniasis (AU)

Marmosets in New World leishmaniasis research.

In leishmaniasis, the search for a suitable experimental animal model is highly recommended, especially in Leishmania (Viannia) braziliensis (L. (V) b) research. Diverse species of neotropical primates have increasingly been used as experimental hosts of Leishmania. This article describes aspects of parasite L(V)b and marmoset, Callithrix penicillata (Primates, Callithricidae), interaction and summarizes the biology of parasitism in this primate model. Results of recent studies on primary infections with several strains of L(V)b as well as parasitism evolution, clinical outcome patterns and immunoprotection experiments, are summarily discussed. The relevance of homologous reinfection experiments for vaccine development in leishmaniasis is discussed.

Marmosets in New World leishmaniasis research.

In leishmaniasis, the search for a suitable experimental animal model is highly recommended, especially in Leishmania (Viannia) braziliensis (L. (V) b) research. Diverse species of neotropical primates have increasingly been used as experimental hosts of Leishmania. This article describes aspects of parasite L(V)b and marmoset, Callithrix penicillata (Primates, Callithricidae), interaction and summarizes the biology of parasitism in this primate model. Results of recent studies on primary infections with several strains of L(V)b as well as parasitism evolution, clinical outcome patterns and immunoprotection experiments, are summarily discussed. The relevance of homologous reinfection experiments for vaccine development in leishmaniasis is discussed.

Clonal variation within a mucosal isolate derived from a patient with Leishmania (Viannia) braziliensis infection.

Three isolates over 5 years from a patient with persistent relapsing mucosal leishmaniasis due to Leishmania (Viannia) braziliensis and 7 clones from one of these isolates were studied by zymodemes and serodemes analysis. Results showed evidences of clonal phenotypic variation. Eight isoenzymes markers demonstrated clear differences on Cellulose Acetate (CA) and thin starch gel electrophoresis. Also a panel of specific monoclonal antibodies showed such differences. Our observations provide additional evidence that Leishmania (Viannia) braziliensis is composed by subpopulations of parasites with peculiar biochemical and antigenic characteristics.

A focus of mucocutaneous leishmaniasis in Três Braços, Bahia, Brazil: characterization and identification of Leishmania stocks isolated from man and dogs.

The characterization and identification to species and subspecies of 20 stocks of Leishmania isolated from the region of Três Braços, Bahia, Brazil, are described: 17 stocks were from patients and three from dogs. The following techniques were used (i) biological (growth in culture, hamster tissues and phlebotomine gut), (ii) biochemical (isoenzyme and kinetoplast DNA analysis) and (iii) immunological (using monoclonal antibodies). All except two stocks belong to the L. braziliensis complex. One of these two corresponded to L. mexicana amazonensis but the other, while clearly in the mexicana complex, showed slight differences from the L. mexicana amazonensis reference strain on isoenzyme analysis. Two stocks from different lesions in the same patient and with different growth characteristics in hamster tissues were both identified as L. braziliensis braziliensis. All the fully characterized stocks of the L. braziliensis complex were identified as L. braziliensis braziliensis. L. braziliensis guyanensis was not identified. Dog and human stocks of L. braziliensis braziliensis were indistinguishable. From these findings and other evidence, L. braziliensis braziliensis seems to be the predominant species transmitted in Três Braços.