Leishmania infantum and Toxoplasma gondii: Mixed infection of macrophages in vitro and in vivo

Exp Parasitol. 2011 Feb 24. [Epub ahead of print]

Leishmania infantum and Toxoplasma gondii: Mixed infection of macrophages in vitro and in vivo

Christodoulou V, Messaritakis I, Svirinaki E, Tsatsanis C, Antoniou M.

Laboratory of Clinical Bacteriology, Parasitology, Zoonoses, and Geographical Medicine, Faculty of Medicine, University of Crete, Crete, Greece.

Abstract
Although macrophages have a microbicidal role in the immune system they themselves can be infected by pathogens. Often a simultaneous infection by more than one microbe may occur in a single cell. This is the first report of coinfection of macrophages with Toxoplasma gondii and Leishmania infantum, in vitro and in vivo. L. infantum does not cause severe disease in mice but T. gondii, RH strain, is lethal. Cell culture studies using THP-1 macrophages dually infected in vitro revealed that 4.3% harbored both parasites 24hrs after infection. When mice were infected with both parasites on the same day 7.3% of the infected cells carried both parasites 7 days later. Yet, if mice were first infected with L. infantum and then with Toxoplasma (5 days post infection) 18.7% of the macrophages hosted either parasite but concomitant infection could not be found and mice, already harboring L. infantum, survived Toxoplasma's lethal effect.

Copyright © 2011. Published by Elsevier Inc.
PMID: 21354140 [PubMed - as supplied by publisher]