title: Exploring the immune response of porcine mesenteric lymph nodes to Salmonella enterica serovar Typhimurium: an analysis of transcriptional changes, morphological alterations and pathogen burden.
abstract: Infections caused by Salmonella enterica serovar Typhimurium (S. typhimurium) cause important economic problems in the swine industry and threaten the integrity of a safe and healthy food supply. Controlling the prevalence of Salmonella in pig production requires a thorough knowledge of the response processes that occurs in the gut associated immune tissues. To explore the in vivo porcine response to S. typhimurium, MLN samples from four control pigs and twelve infected animals at 1, 2 and 6 days post infection (dpi) were collected to quantify the mRNA expression of gene coding for 42 innate immune-related molecules. In addition, the presence of S. typhimurium in MLN was examined and its effect on tissue micro-anatomy. Higher S. typhimurium loads were observed at 2dpi, triggering an innate immune response, marked by a substantial infiltration of phagocytes and up-regulation of pro-inflammatory genes. Such response resulted in a significant decrease in pathogen burden in MLN at 6dpi, although Salmonella could not be completely eliminated from tissue. Furthermore, our results suggest that in porcine infections, S. typhimurium might interferes with dendritic cell-T cell interactions and this strategy could be involved in the conversion of Salmonella infected pigs to a carrier state.
authors.affiliation: Grupo de Genómica y Mejora Animal, Departamento de Genética, Universidad de Córdoba, Campus de Rabanales, Edificio Gregor Mendel C5, 14071 Córdoba, Spain.
authors.forename: Rodrigo Prado
authors.initials: RP
authors.lastname: Martins
authors.forename: Melania
authors.initials: M
authors.lastname: Collado-Romero
authors.forename: Cristina
authors.initials: C
authors.lastname: Arce
authors.forename: Concepción
authors.initials: C
authors.lastname: Lucena
authors.forename: Ana
authors.initials: A
authors.lastname: Carvajal
authors.forename: Juan J
authors.initials: JJ
authors.lastname: Garrido
mesh_terms: D000818:Animals; D016000:Cluster Analysis; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D007958:Leukocyte Count; D008198:Lymph Nodes / Q000276:immunology* / Q000378:metabolism* / Q000382:microbiology; D008643:Mesentery; D010586:Phagocytes / Q000276:immunology; D012481:Salmonella Infections, Animal / Q000235:genetics / Q000276:immunology* / Q000382:microbiology / Q000473:pathology; D012486:Salmonella typhimurium / Q000276:immunology*; D013552:Swine; D013553:Swine Diseases / Q000235:genetics / Q000276:immunology* / Q000382:microbiology / Q000473:pathology; D014158:Transcription, Genetic