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Both <i>Eimeria tenella</i> and <i>Toxoplasma gondii</i> are common apicomplexan parasites in chickens. Host cell invasion by both protozoans includes gliding motility, host cell attachment and active penetration. Chicken macrophages as phagocytic cells participate in the innate host immune response against these two parasites. In this study, primary chicken monocyte-derived macrophages (MM) were infected with both pathogens to investigate mutual and host–parasite interactions. MM cultures were assigned to groups that were infected with <i>E. tenella</i>, <i>T. gondii</i> or both. In co-infected cultures, MM were first exposed to <i>E. tenella</i> sporozoites for 2 h. Afterwards, <i>T. gondii</i> tachyzoite infection was performed. Live-cell imaging was carried out to observe cell invasion and survival of <i>T. gondii</i> by single parasite tracking over a period of 20 h post infection (hpi). Quantitative analysis for parasite replication was performed by real-time quantitative PCR (qPCR) at 2, 6, 12 and 24 hpi. Overall, the ability of <i>T. gondii</i> to penetrate the cell membrane of the potential host cell was reduced, although high motility was displayed. We found that <i>T. gondii</i> tachyzoites adhered for more than 4 h to macrophages during early co-infection. qPCR results confirmed that significantly less <i>T. gondii</i> entered in <i>E. tenella</i>-activated MM at 2 hpi, and a reduced proportion of intracellular <i>T. gondii</i> survived and replicated in these cells at 24 hpi. We conclude that <i>E. tenella</i> modulates host cell responses to another apicomplexan agent, <i>T. gondii,</i> reducing active invasion and multiplication in chicken primary macrophages.