Resumo

GRATEROL, Diana et al. Morphological, protein, glycoprotein and antigenic changes of Trypanosoma cruzi cultured in axenic medium with different oxygen tensions. Salus [online]. 2013, vol.17, suppl.1, pp.02-13. ISSN 1316-7138.

Axenic culture of epimastigote-derived amastigotes of Trypanosoma cruzi has been reported. Have been inquired why round forms appear in culture media and if are true amastigotes. Our proposal was study molecular and biological changes in epimastigotes growing in high and low oxygen tension. T. cruzi (EPm6) were grown in flasks with different height of LITB medium (horizontal condition 3 mm and vertical 83 mm). Parasites were collected masses of different times of growth for proteins, glycoproteins and antigenic analysis. Morphological changes, increase of inoculum and resistance to complement lyses were studied in phase’s microscopy and Giemsa-stained smears. Protein and glycoprotein changes were compared by SDS-PAGE. Antigenic changes were analyzed by Western blot with rabbit serum and IgY antibody against amastigote forms. In vertical condition, the epimastigote maintained its typical morphology along the growth curve and not showed significant molecular changes. In horizontal condition round forms prevailed at 4 and 6 days with capacity to resist lyses by complement. From the 4th day changes in proteins and glycoproteins profiles were observed, concomitantly with the morphological changes. Anti-amastigotes serum revealed a 55 kDa transitory amastigote-specific antigen in four day parasites’ from horizontal condition, while IgY antibody anti-amastigotes don’t revealed differences between parasites grown in both conditions. These evidences suggest that epimastigotes of T. cruzi conditioned to survive in high oxygen tension can mimic biological and antigenic properties own the amastigote-stage.

Palavras-chave : Trypanosoma cruzi; oxygen tension; round forms; axenic culture.

        · resumo em Espanhol     · texto em Espanhol     · Espanhol ( pdf )