Towards the Establishment of a Porcine Model to Study Human Amebiasis

Abstract

Background Entamoeba histolytica is an important parasite of the human intestine. Its life cycle is monoxenous with two stages: (i) the trophozoite, growing in the intestine and (ii) the cyst corresponding to the dissemination stage. The trophozoite in the intestine can live as a commensal leading to asymptomatic infection or as a tissue invasive form producing mucosal ulcers and liver abscesses. There is no animal model mimicking the whole disease cycle. Most of the biological information on E. histolytica has been obtained from trophozoite adapted to axenic culture. The reproduction of intestinal amebiasis in an animal model is difficult while for liver amebiasis there are well-described rodent models. During this study, we worked on the assessment of pigs as a new potential model to study amebiasis.Methodology/Principal FindingsWe first co-cultured trophozoites of E. histolytica with porcine colonic fragments and observed a disruption of the mucosal architecture. Then, we showed that outbred pigs can be used to reproduce some lesions associated with human amebiasis. A detailed analysis was performed using a washed closed-jejunal loops model. In loops inoculated with virulent amebas a severe acute ulcerative jejunitis was observed with large hemorrhagic lesions 14 days post-inoculation associated with the presence of the trophozoites in the depth of the mucosa in two out four animals. Furthermore, typical large sized hepatic abscesses were observed in the liver of one animal 7 days post-injection in the portal vein and the liver parenchyma.ConclusionsThe pig model could help with simultaneously studying intestinal and extraintestinal lesion development.

Entamoeba histolytica: a snapshot of current research and methods for genetic analysis

“…Many animal models were tested including dogs and kittens, rats, gerbils and pigs [39]. A recent study used baboons with the goal to establish a suitable primate model to study in vivo E. histolytica intestinal infection and colitis [40].…”

Nivalenol Has a Greater Impact than Deoxynivalenol on Pig Jejunum Mucosa in Vitro on Explants and in Vivo on Intestinal Loops

“…A 1-m long segment of intestine was surgically prepared in the jejunum, to constitute the loops as previously described [ 19 , 45 ]. This segment was then subdivided into consecutive segments, designated as “loops” (10 cm long, 6 loops), separated by “inter-loops”.…”

Molecular biology research to benefit patients with Entamoeba histolytica infection

“…However, murine infection models require the direct injection of trophozoites into the target organ (cecum or liver). Although Girald-Misguich et al succeeded to make ALA by injection of trophozoites into the portal vein in pigs (Girard-Misguich et al, 2011), there is not an in vivo experimental model that fully recapitulates natural infection with the cyst form. Explants of human colon are another useful model, and have clearly shown visible morphologic changes and transcriptome profiles during tissue invasion by the trophozoite (Bansal et al, 2009;Thibeaux et al, 2012;.…”