Strain-dependent host responses in chicken embryonic fibroblasts infected with Toxoplasma gondii [ME49, CEP, and Mock]
Ontology highlight
ABSTRACT: Toxoplasma gondii is a ubiquitous protozoan pathogen able to infect both mammalian and avian hosts. Surprisingly, just three strains appear to account for the majority of isolates from Europe and N. America. To test the hypothesis that strain divergence might be driven by differences between mammalian and avian response to infection, we examine in vitro strain-dependent host responses in a representative avian host, the chicken.
Project description:Toxoplasma gondii is a ubiquitous protozoan pathogen able to infect both mammalian and avian hosts. Surprisingly, just three strains appear to account for the majority of isolates from Europe and N. America. To test the hypothesis that strain divergence might be driven by differences between mammalian and avian response to infection, we examine in vitro strain-dependent host responses in a representative avian host, the chicken. Chicken embryonic fibroblasts were cultivated in vitro and infected with different strains of Toxoplasma gondii (Type II = ME49, Type III = CEP); host transcriptional responses were then analyzed at 24 hours post-infection.
Project description:Toxoplasma gondii is a ubiquitous protozoan pathogen able to infect both mammalian and avian hosts. Surprisingly, just three strains appear to account for the majority of isolates from Europe and N. America. To test the hypothesis that strain divergence might be driven by differences between mammalian and avian response to infection, we examine in vitro strain-dependent host responses in a representative avian host, the chicken.
Project description:Toxoplasma gondii is a ubiquitous protozoan pathogen able to infect both mammalian and avian hosts. Surprisingly, just three strains appear to account for the majority of isolates from Europe and N. America. To test the hypothesis that strain divergence might be driven by differences between mammalian and avian response to infection, we examine in vitro strain-dependent host responses in a representative avian host, the chicken. Chicken embryonic fibroblasts were cultivated in vitro and infected with different strains of Toxoplasma gondii; host transcriptional responses were then analyzed at 24 hours post-infection.
Project description:Toxoplasma gondii is a ubiquitous protozoan pathogen able to infect both mammalian and avian hosts. Surprisingly, just three strains appear to account for the majority of isolates from Europe and N. America. To test the hypothesis that strain divergence might be driven by differences between mammalian and avian response to infection, we examine in vitro strain-dependent host responses in a representative avian host, the chicken. To identify parasite drivers of strain-dependent host response, QTL mapping was used; analysis revealed a locus on Toxoplasma chromosome VIIb. To determine whether this was the parasite gene ROP16, array analysis was performed on chicken embryonic fibroblasts infected with Type I parasites and ROP16-KO parasites (of a Type I background).
Project description:Toxoplasma gondii is a ubiquitous protozoan pathogen able to infect both mammalian and avian hosts. Surprisingly, just three strains appear to account for the majority of isolates from Europe and N. America. To test the hypothesis that strain divergence might be driven by differences between mammalian and avian response to infection, we examine in vitro strain-dependent host responses in a representative avian host, the chicken. To identify parasite drivers of strain-dependent host response, QTL mapping was used; analysis revealed a locus on Toxoplasma chromosome VIIb. To determine whether this was the parasite gene ROP16, array analysis was performed on chicken embryonic fibroblasts infected with Type I parasites and ROP16-KO parasites (of a Type I background). Chicken embryonic fibroblasts were cultivated in vitro and infected with either Type I (RH) parasites or Type I ROP16-KO parasites; ROP16-dependent host transcriptional responses were then analyzed at 5 hours post-infection.
Project description:Previous studies suggested that specific bradyzoite genes were differentially expressed in the three major lineages common to North America and Europe (Radke et al., 2006). In order to determine if these differences extended to the global transcriptome, we characterized whole-cell mRNA levels in both tachyzoite and bradyzoite populations from three primary strain isolates differentiated in vitro. It is well understood in the field that long passage history is associated with the loss of developmental competence (Frenkel et al., 1976). Therefore, the Type I-GT1, Type II-Me49B7 and Type III-CTG strains studied here were maintained at < 20 cell culture passages from the oocyst stage and are capable of completing both intermediate and definitive host life cycles. These experiments used newly constructed Affymetrix GeneChips that include probe sets for ~8000 genes, and we assessed the induction of bradyzoite genes using a strong inducer of bradyzoite differentiation, Compound 1 (Radke et al., 2006).
Project description:Previous studies suggested that specific bradyzoite genes were differentially expressed in the three major lineages common to North America and Europe (Radke et al., 2006). In order to determine if these differences extended to the global transcriptome, we characterized whole-cell mRNA levels in both tachyzoite and bradyzoite populations from three primary strain isolates differentiated in vitro. It is well understood in the field that long passage history is associated with the loss of developmental competence (Frenkel et al., 1976). Therefore, the Type I-GT1, Type II-Me49B7 and Type III-CTG strains studied here were maintained at < 20 cell culture passages from the oocyst stage and are capable of completing both intermediate and definitive host life cycles. These experiments used newly constructed Affymetrix GeneChips that include probe sets for ~8000 genes, and we assessed the induction of bradyzoite genes using a strong inducer of bradyzoite differentiation, Compound 1 (Radke et al., 2006). Both tachyzoite and induced (Compound 1/48hrs - bradyzoite) RNA for strains representing the three major lineages of Toxoplasma gondii were hybridized .
Project description:Methicillin-resistant Staphylococcus aureus clonal complex (CC) 398 has emerged from pigs to cause human infections in Europe and North America. We used a new 62-strain S. aureus microarray (SAM-62) to compare genomes of isolates from three geographical areas (Belgium, Denmark, and Netherlands) to understand how CC398 colonizes different mammalian hosts. The core genomes of 44 pig isolates and 32 isolates from humans did not vary. However, mobile genetic element (MGE) distribution was variable including SCCmec. Phi3 bacteriophage and human specificity genes (chp, sak, scn) were found in invasive human but not pig isolates. SaPI5 and putative ruminant specificity gene variants (vwb and scn) were common but not pig specific. Virulence and resistance gene carriage was host associated but country specific. We conclude MGE exchange is frequent in CC398 and greatest among populations in close contact. This feature may help determine epidemiological associations among isolates of the same lineage. [Data is also available from http://bugs.sgul.ac.uk/E-BUGS-120]
Project description:The principal objective of this work was to investigate the somatic copy number changes that influence the risk of head and neck cancer occurrence and outcome from two large comprehensive case series in Europe and South America. A second objective was to investigate how these somatic changes interact with environmental and host risk factors such including HPV infection, alcohol and smoking.
Project description:Expression profiling of the three clonotypic lineages dominating T. gondii populations in North America and Europe provides a first comprehensive view of the parasite transcriptome.