Project description:Gene expression profiling of clostridium perfringens infection in broilers on medicated and non-medicated diets using chicken 44k agilent microarray. To elucidate molecular and ceelular mechanisms of bacitracin effect on CP infection in chickens by microarray technology.
Project description:Necrotic enteritis is a disease caused by Clostridium perfringens, which threatens poultry production in the absence of dietary antibiotics. A total number of 144 Ross broilers were reared in 12 pens with each hosting 12 birds. Each 6 pens of birds were fed medicated (bacitracin at 55 ppm) or non-medicated starter diets (Nutreco Canada Agresearch) immediately after the chicks were placed. At day 18, birds were challenged with C. perfringens (107 cfu per ml mixed with feed). Spleens were collected from 12 birds of each group at day 18 (before infection), 19, 20, and 22. A low-density chicken immune microarray was used to study gene expression profiling of host response to C. perfringens infection. Six biological replicates (2 birds per biological replicate) for each treatment group were labeled with either Cy5 or Cy3 with dye swap. A total of 24 arrays were used for this study. Gene signal intensity was globally normalized by LOWESS and expressed as log2 ratios. A mixed model including treatment, time, array, subgrid (random effect), dye, and all interactions among treatment and time was used to identify differentially expressed genes between post-infection vs. pre-infection, among post-infections, and between medication treatments, at the 5% significance level. The results indicated subtle medication effects on gene expression of these immune-related genes compared to bacterial infection effect. Our findings strongly suggest that both cell-mediated and antibody-mediated immune responses via MHC class I and II systems were actively involved in the host defense against C. perfringens infection in broilers. The unique cytokine signaling pathway and apoptosis cascade found in the study provide a new insight of molecular regulation of host immune response. Collectively, the findings of the present study will shed light on the molecular mechanisms underlying C. perfringens infection in broilers.
Project description:Necrotic enteritis is a disease caused by Clostridium perfringens, which threatens poultry production in the absence of dietary antibiotics. A total number of 144 Ross broilers were reared in 12 pens with each hosting 12 birds. Each 6 pens of birds were fed medicated (bacitracin at 55 ppm) or non-medicated starter diets (Nutreco Canada Agresearch) immediately after the chicks were placed. At day 18, birds were challenged with C. perfringens (107 cfu per ml mixed with feed). Spleens were collected from 12 birds of each group at day 18 (before infection), 19, 20, and 22. A low-density chicken immune microarray was used to study gene expression profiling of host response to C. perfringens infection. Six biological replicates (2 birds per biological replicate) for each treatment group were labeled with either Cy5 or Cy3 with dye swap. A total of 24 arrays were used for this study. Gene signal intensity was globally normalized by LOWESS and expressed as log2 ratios. A mixed model including treatment, time, array, subgrid (random effect), dye, and all interactions among treatment and time was used to identify differentially expressed genes between post-infection vs. pre-infection, among post-infections, and between medication treatments, at the 5% significance level. The results indicated subtle medication effects on gene expression of these immune-related genes compared to bacterial infection effect. Our findings strongly suggest that both cell-mediated and antibody-mediated immune responses via MHC class I and II systems were actively involved in the host defense against C. perfringens infection in broilers. The unique cytokine signaling pathway and apoptosis cascade found in the study provide a new insight of molecular regulation of host immune response. Collectively, the findings of the present study will shed light on the molecular mechanisms underlying C. perfringens infection in broilers. There were two groups: medicated and non-medicated. Spleen were collected to isolate total RNA for gene expression profiling.For the microarray study, two birds from each pen were pooled within each group. To account for any bias inherent to the fluorescent dyes, three of the six medicated replicates were labeled with Cy3 and the other three were labeled with Cy5 at each time point. The same design was applied for the non-medicated group. There were six hybridizations between medicated and non-medicated replicates at each time point. Twenty-three out of 24 arrays were used (data from one array were discarded due to poor quality).
Project description:Gene expression profiling of clostridium perfringens infection in broilers on medicated and non-medicated diets using chicken 44k agilent microarray. To elucidate molecular and ceelular mechanisms of bacitracin effect on CP infection in chickens by microarray technology. A total number of 600 Ross broilers were reared in 12 pens with each hosting 50 birds. Each 6 pens of birds were fed bacitracin-medicated (55 ppm) or non-medicated starter diets immediately after the chicks were placed. At day 18, birds were challenged with CP. Spleens were collected from 12 birds of each group at day 18 (before infection), 19, 20, and 22. Total RNA was labeled by Cy3 or Cy5 with dye swap. Gene signal intensity was globally normalized by LOWESS and expressed on natural log scale. A mixed model including treatment, time, array (random effect), dye, and all interactions among treatment, time was used to identify differentially expressed genes between treatments, at the 1% significance level.
Project description:Purpose: The purpose of this study is to clarify the response of Clostridium perfringens ATCC 13124 to host polysaccharide. Methods: Clostridium perfringens ATCC 13124 cells were cultured anaerobically in a medium containing Minimal medium-like condition Poor + medium, medium in which hyaluronic acid or mucin was added to Poor + medium. Total RNA was extracted from bacterial cells by the Hot-Phenol method. Samples for RNA-seq were prepared according to the Illmina protocol available from the manufacturer. Array leads passed through quality filters were analyzed at the transcript isoform level using bowtie v 1.1.2. Results: Using the optimized data analysis workflow, we mapped about 50 million sequence leads per sample to the whole genome of Clostridium perfringens ATCC 13124. In addition, 2735 transcripts in C. perfringens ATCC 13124 were identified using a Bowtie aligner. Lead counts per genome were extracted from known gene annotations using the HTSeq program.
Project description:RNA-seq was employed for comparative analysis of the transcriptomes of both the pathogen and the host in C. perfringens-infected murine muscle lesions. The aim was to identify C. perfringens genes that were induced in the host environment and host signaling cascades that were activated in response to a C. perfringens infection.
Project description:Upon infection, pathogens reprogram host gene expression. In eukaryotic cells, genetic reprogramming is induced by the concerted activation/repression of transcription factors and various histone modifications that control DNA accessibility in chromatin. We report here that the bacterial pathogen, Listeria monocytogenes, induces a dramatic dephosphorylation of histone H3 as well as a deacetylation of histone H4 during early phases of infection. This effect is mediated by the major listerial toxin listeriolysin (LLO), in a pore forming independent manner. Strikingly, a similar effect is also observed with other toxins of the same family, such as Clostridium perfringens perfringolysin (PFO) and Streptococcus pneumoniae pneumolysin (PLY). The decreased levels of histone modifications correlate with a reduced transcriptional activity of a subset of host genes, including key immunity genes. Thus, manipulation of the epigenetic information emerges here as an unsuspected function shared by several bacterial toxins, highlighting a common strategy used by intracellular and extracellular pathogens to modulate the host response early during infection.
Project description:With the development of the poultry industry, ammonia, as a main contaminant in the air, is causing increasing problems with broiler health. To date, most studies of ammonia toxicity have focused on the nervous system and the gastrointestinal tract in mammals. However, few detailed studies have been conducted on the hepatic response to ammonia toxicity in poultry. The molecular mechanisms that underlie these effects remain unclear. In the present study, our group applied isobaric tags for relative and absolute quantitation (iTRAQ) - based quantitative proteomic analysis to investigate changes in the protein profile change in hepatic tissue of broilers exposed to high concentrations of atmospheric ammonia, with the goal of characterizing the molecular mechanisms of chronic liver injury from exposure to high ambient levels of ammonia. Overall, 30 differentially expressed proteins that are involved in nutrient metabolism (energy, lipid and amino acid), immune response, transcriptional and translational regulation, stress response and detoxification were identified. In particular, two of these proteins, beta-1 galactosidase (GLB1), and a kinase (PRKA) anchor protein 8-like (AKAP8 L), were previously suggested to be potential biomarkers of chronic liver injury. In addition to the changes in the protein profile, serum parameters and histochemical analyses of hepatic tissue also showed extensive hepatic damage in ammonia-exposed broilers. Altogether, these findings suggest that longtime exposure to high concentrations of atmospheric ammonia can trigger chronic hepatic injury in broilers via different mechanisms, providing new information that can be used for intervention using nutritional strategies in the future.
Project description:Purpose: RNA-Seq has become a powerful tool for investigating transcriptional profiles in gene expression analysis, which would help to reveal the molecular mechanism of Clostridium perfringens type C infecting the piglets. In this study, we analyzed the transcriptome profiles of the spleen of piglets caused by Clostridium perfringens type Cens type C. Methods: 30 normal 7-day-old piglets (Y x L), without infecting Clostridium perfringens type C, Escherichia coli and Salmonella, were selected as experimental subjects. 25 piglets were randomly selected as the experimental group, which were disposed once a day for 5 days. Each piglet was dosed with 1 ml of bouillon culture-medium inoculated Clostridium perfringens type C at 37℃ for 16h, which approximate to 1 x109 CFU per ml. Then, 5 piglets were randomly selected as the control group (SC), which were taken the equal volume medium for 5 days.Based on total diarrhea scores, 25 piglets were ranked from high to low. The top and last five piglet were considered as sensitive group (SS) and resistant group (SR), respectively. Finally, spleen were collected and sequenced for lncRNA and mRNA. Results: RNA libraries constructed from spleen of piglets caused by Clostridium perfringens type C were sequenced. A total of 1,450,292,484 clean reads were generated. Among them, 2056 novel lncRNA transcripts corresponding to 1561 lncRNA genes were identified, including 1811 intergenic lncRNAs and 245 anti-sense lncRNAs. The identified spleen lncRNAs shared some characteristics, such as fewer exons and shorter length, with the lncRNAs in other animal. Notably, in pairwise comparisons between the libraries of spleen tissue at the different group, a total of 247 lncRNA and 2170 mRNA were differentially expressed (P < 0.05). Function analyses indicated that these differentially expressed lncRNAs and mRNAs play roles in defensing Clostridium perfringens type C, which were enriched in immune-related biological processes, such as the antigen processing and presentation, TNF signaling pathway, NF-kappa B signaling pathway, B cell receptor signaling pathway and MAPK signaling pathway. Conclusions: This study provides the information of spleen-related lncRNAs in swine diarrhea with Clostridium perfringens type C. We also analyzed all lncRNA’s genomic feature and expression. Bioinformatic analysis indicates that some lncRNAs participated in important biological processes associated with defeasing Clostridium perfringens type C, such as antigen processing and presentation, the MHC protein complex and regulation of autophagy.