Trypanosoma cruzi: Genetic diversity influences the profile of immunoglobulins during experimental infection.
The clonal evolution model postulated for Trypanosoma cruzi predicts a correlation between the phylogenetic divergence of T. cruzi clonal genotypes and their biological properties. In the present study, the linkage between phylogenetic divergence of the parasite and IgG, IgG1, IgG2a and IgG2b response has been evaluated during the acute and chronic phases of the experimental infection. Eight laboratory-cloned stocks representative of this phylogenetic diversity and including the lineages T. cruzi I (genotypes 19 and 20), T. cruzi II (genotype 32) and T. cruzi (genotype 39) have been studied. The results showed that the pattern of humoral immune response was correlated with T. cruzi genotype, and that stocks included in genotype 20 were responsible for the high IgG response in the acute and chronic phases. Moreover, T. cruzi I lineage was more efficient in over-expressing all subclasses of specific anti-parasite IgG than either T. cruzi II or T. cruzi lineages. Curiously, the alteration in the pattern of antibodies induced by Benznidazole treatment was related to the phase of the infection but not to the genotype of the parasite. The data suggest that genotypes of T. cruzi are able to drive levels/subclasses of specific IgG, hence giving rise to further concerns about the sensitivity of serological assays in the diagnosis of human Chagas disease.
Núcleo de Pesquisas em Ciências Biológicas', Universidade Federal de Ouro Preto, Ouro Preto, MG 35400-000, Brazil.
Daniela Maria
DM
dos Santos
André
A
Talvani
Paulo Marcos da Mata
PM
Guedes
George Luiz Lins
GL
Machado-Coelho
Marta
M
de Lana
Maria Terezinha
MT
Bahia
D000208:Acute Disease; D000818:Animals; D014355:Chagas Disease / Q000188:drug therapy / Q000276:immunology* / Q000469:parasitology; D002908:Chronic Disease; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D014644:Genetic Variation / Q000276:immunology*; D005838:Genotype; D007074:Immunoglobulin G / Q000096:biosynthesis / Q000097:blood* / Q000145:classification; D051379:Mice; D009593:Nitroimidazoles / Q000494:pharmacology / Q000627:therapeutic use; D010802:Phylogeny; D011897:Random Allocation; D013997:Time Factors; D014344:Trypanocidal Agents / Q000494:pharmacology / Q000627:therapeutic use; D014349:Trypanosoma cruzi / Q000187:drug effects / Q000235:genetics* / Q000276:immunology
D007074:Immunoglobulin G; D009593:Nitroimidazoles; D014344:Trypanocidal Agents; C009999:benzonidazole