Trypanosoma cruzi in marsupial didelphids (Philander frenata and Didelhis marsupialis): differences in the humoral immune response in natural and experimental infections

Abstract

Philander frenata and Didelphis marsupialis harbor parasitism by Trypanosoma cruzi without developing any apparent disease and on the contrary to D. marsupialis, P. frenata maintains parasitism by T. cruzi II subpopulations. Here we compared the humoral immune response of the two didelphids naturally and experimentally infected with T. cruzi II group, employing SDS-PAGE/Western blot techniques and by an Indirect immunofluorescence assay. We also studied the histopathological pattern of naturally and experimentally infected P. frenata with T. cruzi. P. frenata sera recognized more antigens than D. marsupialis, and the recognition pattern did not show any change over the course of the follow up of both didelphid species. Polypeptides of 66 and 90kDa were the most prominent antigens recognized by both species in the soluble and enriched membrane fractions. P. frenata recognized intensely also a 45kDa antigen. Our findings indicate that: 1) there were no quantitative or qualitative differences in the patent or subpatent phases in the recognition pattern of P. frenata; 2) the significant differences in the recognition pattern of parasitic antigens by P. frenata and D. marsupialis sera suggest that they probably "learned" to live in harmony with T. cruzi by different strategies; 3) although P. frenata do not display apparent disease, tissular lesions tended to be more severe than has been described in D. marsupialis; and 4) Both didelphids probably acquired infection by T. cruzi after their evolutionary divergence.

Trypanosoma cruzi and Chagas' Disease in the United States

“…Experimental inoculation of Monodelphis domestica with TcI, TcII, and TcVI strains resulted in infections, but a North American TcIV isolate failed to establish an infection (242). Collectively, these data suggest that the marsupial genera diverged before the establishment of host relationships with T. cruzi and that utilization of different ecological niches resulted in distinct T. cruzi lineage transmission patterns (163).…”

“…Interestingly, two terrestrial marsupial genera (Philander and Monodelphis) can harbor both TcI and several other genotypes, whereas only TcI has been reported from the arboreal genus Didelphis (163,225,240). The genus Philander also displays a more severe inflammatory response to T. cruzi (162,163).…”

“…The genus Philander also displays a more severe inflammatory response to T. cruzi (162,163). Experimental inoculation of Monodelphis domestica with TcI, TcII, and TcVI strains resulted in infections, but a North American TcIV isolate failed to establish an infection (242).…”

Ecological host fitting of Trypanosoma cruzi TcI in Bolivia: mosaic population structure, hybridization and a role for humans in Andean parasite dispersal

“…Most lowland parasites were isolated from Didelphimorphia mammals, prominent disease reservoirs which are susceptible to high circulating parasitaemia (Legey et al . 2003) and have a propensity for nonvectoral routes of infection, including oral transmission via predation of infected vectors or mammals (Jansen & Roque 2010; Rocha et al . 2013) and exposure to contaminated anal scent gland secretions (Carreira et al .…”

Coexistence of Trypanosoma cruzi Genotypes in Wild and Periodomestic Mammals in Chile

“…14 However, in more ancestral mammals, experimental infections should not be considered benign. 15,16 This observation suggests that those mammals of greater antiquity in the Americas have had a longer association with T. cruzi, which enables some degree of host-parasite coevolution that results in attenuated pathogenicity. 14 Trypanosoma cruzi genotypes are complex multiclonal populations that propagate asexually and differ in their genetic and biologic characteristics and behavior in vertebrate hosts.…”