ABSTRACT: Genome-wide transcriptional changes in the Clostridium perfringens-afflicted chicken intestine in an avian necrotic enteritis (NE) disease model
Project description:Purpose: Analyze gene expression of necrotic enteritis C. perfringens in intestinal chicken loops comparing with in vitro conditions
Project description:Clostridium perfringens encodes at least two different quorum sensing (QS) systems, the Agr-like and LuxS, and recent studies have highlighted their importance in the regulation of toxin production and virulence. The role of QS in the pathogenesis of necrotic enteritis (NE) in poultry and the regulation of NetB, the key toxin involved, has not yet been investigated. We have generated isogenic agrB-null and complemented strains from parent CP1, and demonstrated that the virulence of the agrB-null mutant was strongly attenuated in a chicken NE model system, and restored by complementation. The production of NetB, a key NE-associated toxin, was dramatically reduced in the agrB mutant at both the transcriptional and protein level, though not in a luxS mutant. Transwell assays confirmed that the Agr-like QS system controls NetB production through a diffusible signal. Global gene expression analysis of the agrB mutant identified additional genes modulated by Agr-like QS, including operons related to phospholipid metabolism and adherence, which may also play a role in NE pathogenesis. This study provides the first evidence that the Agr-like QS system is critical for NE pathogenesis, and identifies a number of Agr-regulated genes, most notably the NetB toxin, that are potentially involved in mediating its effects. The Agr-like QS system thus may serve as a target for developing novel interventions to prevent NE in chickens.
Project description:Purpose: Analyze gene expression during C. perfringens colonization in the chicken Transcriptomic profile of mRNA from C. perfrinegns from in vivo and in vitro conditions were determined in biological duplicates by RNA-Seq using Illumina HiSeq 2500 Comparison of gene expression through RNA sequencing of necrotic enteritis C. perfrinegns type A of in vivo (chicken loops) and in vitro (lab culture)
Project description:Comparative genomic analysis of Clostridium perfringens strains Cp#4 and Cp#6 isolated from chickens affected by necrotic enteritis
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.
Project description:Comparative transcriptome analysis by RNAseq of Necrotic Enteritis Clostridium perfringens in ligated intestinal chicken loops and in vitro conditions.
| PRJNA315888 | ENA
Project description:Clostridium perfringens chitinases, key enzymes during early stages of necrotic enteritis in broiler chickens
Project description:H5N1 subtype highly pathogenic avian influenza virus has been spreading to Asia, Eurasia and African coutries. An original or six of recombinant H5N1 subtype influenza viruses with varying survivability were infected to chickens for elucidating genes correlated with pathogenicity. Two chickens were infected with each 10^6EID50/ head virus intranasally, and their lung was collected from infected chicken at 24 hours after infection.