Project description:Poultry products are an important source of Salmonella enterica. An effective way to reduce food poisoning due to Salmonella would be to breed chickens more resistant to Salmonella. Unfortunately resistance to Salmonella is a complex trait with many factors involved. To learn more about Salmonella resistance mechanisms in young chickens, a cDNA microarray analysis was performed to compare gene expression profiles between a Salmonella susceptible and a more resistant chicken line. Newly hatched chickens were orally infected with S. enterica serovar Enteritidis. Since the intestine is the first barrier the bacteria encountersbacteria encounter after oral inoculation, gene expression was investigated in the intestine, from day 1 until day 21 post infection. Differences in gene expression between the susceptible and resistant chicken line were found in control as well as Salmonella infected conditions. In response to the Salmonella infection, the expression of different sets of genes seemed to be affected in the jejunum of the two chicken lines. In the susceptible line this included genes that affect T-cell activation, whereas in the more resistant line, at day 1, macrophage activation seemed to be more affected. At day 7 and 9 most gene expression differences between the two chicken lines were identified under control conditions, indicating a difference in the intestinal development between the two chicken lines which might be linked to the difference in Salmonella susceptibility. The findings in this study have lead to the identification of novel genes and possible cellular pathways of the host involved in Salmonella susceptibility. Keywords: timecourse, disease
Project description:Humans and animals encounter a summation of exposures during their lifetime (the exposome). In recent years, the scope of the exposome has begun to include microplastics. Microplastics (MPs) have increasingly been found in locations where there could be an interaction with Salmonella enterica Typhimurium, one of the commonly isolated serovars from processed chicken. In this study, the microbiota response to a 24-hour co-exposure to Salmonella enterica Typhimurium and/or low-density polyethylene (PE) microplastics in an in vitro broiler cecal model was determined using 16S rRNA amplicon sequencing (Illumina) and untargeted metabolomics. Community sequencing results indicated that PE fiber with and without S. Typhimurium yielded a lower Firmicutes/Bacteroides ratio compared to other treatment groups, which is associated with poor gut health, and overall had greater changes to the cecal microbial community composition. However, changes in the total metabolome were primarily driven by the presence of S. Typhimurium. Additionally, the co-exposure to PE Fiber and S. Typhimurium caused greater cecal microbial community and metabolome changes than either exposure alone. Our results indicate that polymer shape is an important factor in effects resulting from exposure. It also demonstrates that microplastic-pathogen interactions cause metabolic alterations to the chicken cecal microbiome in an in vitro chicken cecal model.
Project description:Salmonella enterica Pullorum(S. Pullorum) is one of the most important pathogens in poultry. A better understanding of the immune response and molecular modulation resulting from infection by S. Pullorum will facilitates the control of this pathogen. In this study, we determined the relationships among identified differential expressed genes (DEGs) and pathways via deeply mining microarray data from Guangxi Huang Chicken challenged with S. Pullorum.
Project description:Salmonella enterica is one of the most important foodborne pathogens that infect a variety of animals and birds. In humans, S. Typhimurium causes gastroenteritis, leading to vomiting, diarrhea, fever, and abdominal cramps. We mainly get infected with Salmonella by ingesting comminated poultry products. Therefore, developing an oral live attenuated vaccine for the poultry industry is our best bet against Salmonella infection. In this article, we investigated the potential of the next generation of Salmonella vaccines. We generated a library of potentially attenuated S. Typhimurium mutants and compared fitness to that of a commercial vaccine. We also investigated the invasion and survival potential of these mutants in chicken macrophages. Our data indicate that although these mutants had no significant growth defects, they were much sensitive to macrophage attack. Analyzing the transcriptome data from infected primary chicken macrophages, we concluded that these mutants elicit a robust immune response by activating several immunoregulatory pathways. Our data also indicates that by combining phoPQ deletion with an already existing cya-crp deletion in MeganVac1, a much stronger immune response can be generated.
Project description:Investigation of whole genome gene expression level changes in a Salmonella enterica serovar Typhimurium UK1 delta-iacP mutant, compared to the wild-type strain. IacP is resoponsible for the secretion of virulence effector proteins via the type III secretion system, thereby contributing the virulence of S. Typhimurium. The mutants analyzed in this study are further described in Kim et al. 2011. Role of Salmonella Pathogenicity Island 1 Protein IacP in Salmonella enterica Serovar Typhimurium Pathogenesis. Infection and Immunity 79(4):1440-1450 (PMID 21263021). A chip study using total RNA recovered from two separate wild-type cultures of Salmonella enterica serovar Typhimurium UK1 and two separate cultures of a mutant strain, Salmonella enterica serovar Typhimurium UK1 delta-iacP. Each chip measures the expression level of 4,302 genes from Salmonella enterica serovar Typhimurium.