INVESTIGADORES
CARDINAL Marta Victoria
congresos y reuniones científicas
Título:
Genotipic distribution of T. cruzi lineage I in vectors, reservoirs and humans from endemic countries based on the sequence of the spliced leader intergenic spacer
Autor/es:
CURA C, MEJÍA-JARAMILLO AM, BURGOS J, DUFFY T, DIOSQUE P, CARDINAL MV, DA SILVA A, RUSSOMANDO G, AZNAR C , GURTLER R, TRIANA-CHÁVEZ O, SCHIJMAN AG
Lugar:
Armação dos Búzios, Brasil
Reunión:
Congreso; Congreso.XIII International Congress of Protistology. XXV Annual Meeting of the Brazilian Society of Protozoology. XXXVI Annual Meeting on Basic Research in Chagas Disease; 2009
Resumen:
Natural populations of T.cruzi are
classified into two major groups T. cruzi I and II predominating in the
northern and southern areas of Latin America, respectively. T. cruzi II
has been divided into 5 discrete typing units (a-e) but the high
heterogeneity of T.cruzi I hampered DTUs assessment. In 2007, Herrera et
al. proposed 4 T.cruzi I haplotypes in Colombia, identified by SNPs and
insertions/deletions within a motif at the intergenic spacer of
spliced-leader genes (SL-IR), recently named as TcI ad by Falla et al,
2009. We aimed to characterize this polymorphism in T.cruzi I samples
infecting faeces of Rhodnius, Pastrongylus and Triatoma bugs, wild
reservoirs and blood and tissues from patients of different endemic
areas.The SL-IR was amplified by PCR from 73 samples. PCR with primers
UTCC/Tc2 (475 bp) was applied in culture stocks and heminested-PCR with
primers TCC/Tc2 (350 bp) in clinical samples. Purified amplicons were
sequenced for alignment using MEGA 4.0. Five Argentinean stocks were Tc
Ia and 11 Tc Id. It is worthnoting that Tc Ia or Id was detected in
blood from Chagas Heart disease patients but only Tc Id in cardiac
tissues from explants (4/4), even in a case with mixed Tc Ia/d
infection. Three Brazilian stocks, 3 from French Guiana and 5 from
Paraguay were Tc Id. Three from Mexico and one from Chile were Tc Ia.
Among 37 Colombian strains, 6 were Tc Ia, 17 Tc Id and 14 Tc Ib.
Interestingly, 4 samples from Argentina and 1 from Bolivia had a novel
motif, named Tc Ie. In conclusion, we found association of Tc Ia with
domestic cycles, Tc Ib mainly with sylvatic and peridomestic habitats of
Colombia, 61% of Tc Id with sylvatic cycles but cardiac histotropism in
Chagas heart patients, and Tc Ie with domestic cycle in Argentina and
Bolivia. Tc Ic was not found in our population.