INGEBI   02650
INSTITUTO DE INVESTIGACIONES EN INGENIERIA GENETICA Y BIOLOGIA MOLECULAR "DR. HECTOR N TORRES"
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Identification and follow-up of T. cruzi lineages at sites of Chagas heart disease and clinical reactivation after heart transplantation - Revision and standardization of the nomenclature of the T. cruzi strains
Autor/es:
SCHIJMAN ALEJANDRO GABRIEL
Lugar:
Buzios
Reunión:
Simposio; XIII International Congress of Protistology - XXXVI Annual Meeting on Basic Research in Chagas disease; 2009
Institución organizadora:
Sociedad Brasilera de Protozoología
Resumen:
The pathogenesis of chronic Chagas heart disease (ChHD) is not completely understood, even though parasite persistence in cardiac tissue and abnormalities of the host´s immune system appear involved in progressive heart damage. Heart transplantation is a treatment option for end-stage heart failure. Eleven ChHD pts and 5 seropositive patients with cardiopathies of non Chagasic etiology who underwent heart transplantation were monitored. Six suffered reactivation  within a mean period of 71.6 days after Tx. Parasite persistence was linked to severity of myocarditis. in heart explants. Parasite lineages were characterised by PCRs targeted to  nuclear genomic markers and minicircle signatures. Seven cardiac explants from 11 ChHD pts were PCR positive, 3 harbored Tc I parasites and 4 Tc II b-d-e lineages. Tc I was detected in kin chagomas from 2 pts with reactivation and Tc II in endomyocardial biopsies from 3  cases and kin biopsies from 2 pts with reactivation. The existence of mixed infections with differnt tissue localizations points to differential histotropism and reveals that T.cruzi I exists more frequently in the human infection at the southern cone of America  than it was previously assumed from studies of cultured isolates from patients´blood samples of the same endemic region. Moreover, post-Tx immunosuppression must have favored the proliferation of Tc I parasite populations that otherwise would be undetectable in the chronic phase of disease. s