Metabolomics,Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

Up-regulation of the peroxisome proliferator-activated receptor alpha and gamma pathway in the intestines of Giardia duodenalis infected calves

ABSTRACT: Despite of Giardia duodenalis being one of the most commonly found intestinal pathogens in humans and animals, little is known of the host-parasite interactions in natural hosts. Therefore, the objective of this study was to investigate the intestinal response in calves following a G. duodenalis infection, using a bovine high-density oligo microarray to analyze global gene expression in the small intestine. The resulting microarray data suggested a decrease in inflammation, immune response and immune cell migration in infected animals, which was examined in more detail by quantitative real-time PCR on a panel of cytokines combined with histological analyses. The cytokine transcription levels showed a trend of down regulated expression in infected animals compared to the negative controls, best seen in jejunum for IL-6 and IL-8 and statistically significant for IL-17, IL-13 and IFN-?. No increased immune cell recruitment could be seen after infection, as well as no intestinal pathologies, such as villus shortening or increased levels of apoptosis. Key regulators in this intestinal response seem to be the nuclear peroxisome proliferator-activated receptors alpha (PPARA) and gamma (PPARG), for which an up-regulated expression was seen on microarray and qRT-PCR data. The activation of PPARs can exert an anti-inflammatory effect with inhibition of pro-inflammatory cytokines and a decrease in cell recruitment. . How the PPARs are activated during a Giardia infection still needs to be further elucidated. Eight male Holstein calves aged two to four weeks old were used for the trial. Prior to arrival, all animals were screened for the presence of Giardia cysts in their faecal samples. After confirming their negative status for all these pathogens, four of the animals were randomly chosen and placed in a G. duodenalis contaminated environment, whereas the four remaining animals were kept as negative controls in separate G. duodenalis-free stables. All calves in the study received the same commercial milk replacer. After three weeks, the presence or absence of a G. duodenalis infection was confirmed by IFA on faecal samples after which the animals were euthanized. Changes in gene expression profiles induced by Giardia duodenalis infection were compared using a high-density 60mer bovine oligo microarray.

ORGANISM(S): Bos taurus

SUBMITTER: Robert Li

PROVIDER: E-GEOD-35920 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

ACCESS DATA

Similar Datasets

Project description:Ostertagia ostertagi is considered one of the most economically important bovine parasites. As an alternative for anthelmintic treatment, an experimental host-protective was previously developed based on ASP-proteins derived from the adult worms. Intramuscular injection of this vaccine, combined with QuilA as adjuvant, significantly reduces the faecal egg counts by 60-85%. However, the immunological mechanisms triggered by the vaccine are still unclear. Therefore, in this study, the differences in immune responses at the site of infection, i.e., the abomasal mucosa, between ASP/QuilA-vaccinated animals and QuilA-vaccinated control animals were investigated on a transcriptomic level, using a whole genome bovine microarray, combined with histological analysis. Sixty-nine genes were signicantly impacted in animals protected by the vaccine, 48 of which were upregulated. A correlation study between the parasitological parameters and gene transcription levels showed that the transcription levels of two of the upregulated genes, granulysin (GNLY) and granzyme B (GZMB), negatively correlated to cumulative faecal egg counts and total worm counts, respectively. Both genes also positively correlated to each other, and to another upregulated gene, the IgE receptor subunit FCER1A. Surprisingly, these 3 genes also correlated significantly to CMA1, a mast cell marker, and to cell counts for mast cells and cells previously described as globule leukocytes. Furthermore, immunohistochemical data showed that GNLY was present in the granules of globule leukocytes and that it was secreted in the mucus. Overall, the results suggest a potential role of granule exocytosis by globule leucocytes, potentially IgE-mediated, in the vaccine induced protection against O. ostertagi. 12 helminth‐free Holstein crossbred calves at 7‐10 months of age were randomly divided in 2 groups of 6 animals. All animals were immunized three times intramuscularly in the neck with a three‐week interval. One group received 750 μg of QuilA with Tris‐buffer instead of antigen (negative control). The other group received ~30 μg of the native ASP fraction per immunization in combination with 750 μg of QuilA adjuvant. After the final immunization, the animals were challenged with a trickle infection of 30,000 infective L3 larvae (1,000 L3/day for 30 days, 5 days a week during a period of 6 weeks). 3 weeks after the last challenge infection, all animals were sacrified and total RNA from fundic abomasa was extracted. A total of 12 microarrays were used. Only biological replicates were used.

Project description:Mycobacterium avium subspecies paratuberculosis (MAP) infection is established following the ingestion of bacteria, their penetration of the intestinal mucosa and subsequent events of the host-parasite interaction. These bacteria invade M cells, macrophages and are capable of resisting host defenses and multiply to reach very high numbers intracellular. Mycobactrium avium subsp. avium (MAA) is an antigenically and genetically similar organisms but is relatively nonpathogenic for cattle. MAA organisms appear to infect cattle, but unlike cattle infected with MAP, cattle infected with MAA typically mount an effective systemic immune response, form caseous granuloma, and eliminate the infection. This study was designed to understand the similarities and differences in the host responses during MAP and MAA infection. Neonatal calves were infected (ligated ileal loops) with PBS, MAP, or avirulent MAA following which samples were collected at 30 min, 1h, 2h, 4h, 8h, or 12h. Post-infection, RNA was collected, processed, and then hybridized to custom bovine gene expression arrays, each of which represented 13,258 transcripts spotted in duplicate. Arrays were normalized by scaling against the average reference intensity value (i.e., average across all arrays), normalized by global mean, and then log transformed before statistical analyses were performed. Pairwise comparisons of averaged signal values and StudentM-bM-^@M-^Ys t test were performed using GeneSifter software (VizX Labs, Seattle, WA). A fold-change of at least 1.5-fold and a p value of 0.05 or less was required for a difference in signal to be considered statistically significant. When comparing the transcriptional responses of calves infected with the MAA versus MAP, unique patterns of expression were clearly visible. In general, numbers of transcripts altered in response to infection were much greater for MAA-infected animals than for those infected with the MAP. No genes were significantly up-regulated in MAP-infected animals at the earliest time point tested (30 min), and only modest numbers of genes were increased in expression over the experimental time course. On the other hand, up-regulated transcripts were detected by 30 min in MAA-infected animals and peaked by 2 hr. Differences in the numbers of down-regulated genes between MAP-infected and MAA-infected animals (compared to PBS-infected controls) were less pronounced. At the earliest time points, MAP-infected calves had a greater number of down-regulated genes than did animals infected with MAA. This trend was reversed at 8 and 12 hr post-infection. Keywords: Gene expression profiling by microarray Microarrays were used to examine the transcriptional profiles of bovine intestinal mucosa inoculated with PBS, MAP or MAA and across six time points (30 min, 1, 2, 4, 8, and 12 hours). Experiments were performed in quadruplicate for PBS, MAP, and MAA (bovine ligated ileal loops surgeries were performed with four calves). For one surgery, MAA was used for 4 time ponts only, thus generateing a total of 70 arrays.

Dataset Information

Up-regulation of the peroxisome proliferator-activated receptor alpha and gamma pathway in the intestines of Giardia duodenalis infected calves

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure