In vivo infection by Trypanosoma cruzi: The conserved FLY domain of the gp85/trans-sialidase family potentiates host infection

Author(s)

Tonelli, R. R. ^[1] ; Torrecilhas, A. C. ^[2] ; Jacysyn, J. F. ^[3] ; Juliano, M. A. ^[4] ; Colli, W. ^[2] ; Alves, M. J. M. ^[2]

Affiliation

^[1] Univ Fed Sao Paulo, Dept Microbiol Imunol & Parasitol, Sao Paulo - Brazil

^[2] Univ Sao Paulo, Inst Quim, Dept Bioquim, BR-05508900 Sao Paulo - Brazil

^[3] Univ Sao Paulo, Lab Invest Med LIM 62, Hosp Clin, Fac Med, BR-05508900 Sao Paulo - Brazil

^[4] Univ Fed Sao Paulo, Dept Biofis, Sao Paulo - Brazil

• Document type: Journal article
• Source: Parasitology; v. 138, n. 4, p. 481-492, APR 2011.
• Web of Science Citations: 10

Abstract

Trypanosoma cruzi is a protozoan parasite that infects vertebrates, causing in humans a pathological condition known as Chagas' disease. The infection of host cells by T. cruzi involves a vast collection of molecules, including a family of 85 kDa GPI-anchored glycoproteins belonging to the gp85/trans-sialidase superfamily, which contains a conserved cell-binding sequence (VTVXNVFLYNR) known as FLY, for short. Herein, it is shown that BALB/c mice administered with a single dose (1 mu g/animal, intraperitoneally) of FLY-synthetic peptide are more susceptible to infection by T. cruzi, with increased systemic parasitaemia (2-fold) and mortality. Higher tissue parasitism was observed in bladder (7.6-fold), heart (3-fold) and small intestine (3.6-fold). Moreover, an intense inflammatory response and increment of CD4(+) T cells (1.7-fold) were detected in the heart of FLY-primed and infected animals, with a 5-fold relative increase of CD4(+)CD25(+)FoxP3(+) T (Treg) cells. Mice treated with anti-CD25 antibodies prior to infection, showed a decrease in parasitaemia in the FLY model employed. In conclusion, the results suggest that FLY facilitates in vivo infection by T. cruzi and concurs with other factors to improve parasite survival to such an extent that might influence the progression of pathology in Chagas' disease. (AU)

• FAPESP's process: 04/03303-5 - Interaction between Trypanosoma cruzi and host: binders, receptors and conditioners of intracellular development
• Grantee: Maria Julia Manso Alves
• Support Opportunities: Research Projects - Thematic Grants