Quantitative analysis of the immune response uponSalmonella typhimuriuminfection along the porcine intestinal gut

Abstract

Salmonella enterica serovar Typhimurium causes enteric disease and compromises food safety. In pigs, the molecular response of the intestine to S. typhimurium has been traditionally characterized by in vitro models that do not reflect the actual immunological competence of the intestinal mucosa. In this work, we performed an oral S. typhimurium infection study to obtain insight into the in vitro response in three different sections (jejunum, ileum and colon) of the porcine intestine. For this, samples from one-month-old infected piglets were collected during a time course comprising 1, 2, and 6 days post inoculation to evaluate the intestinal response by quantifying the mRNA expression of gene coding for 28 innate immune system molecules using quantitative real-time PCR assays. In addition, samples from non-infected control animals were also employed to establish differences in the steady state gene expression between intestinal sections. The panel of quantified molecules included an assortment of cytokines, chemokines, pattern-recognition receptors, intracellular signaling molecules, transcription factors and antimicrobial molecules. Changes in gene expression occurred in the three different parts of the intestine and during the course of the S. typhimurium infection. Moreover, the high variation observed in expression patterns of genes coding for inflammatory mediators could indicate that each intestinal section responds differently to the infection. Thus, on the contrary to findings in the jejunum and colon, a down-regulation and lack of induction of some proinflammatory cytokine transcripts was observed in the ileum. Nevertheless, all chemoattractant cytokines assayed were up-regulated in the ileum and jejunum whereas only interleukin-8 and MIP-1α mRNA were over expressed in the colon. In conclusion, our results reveal regional differences in gene expression profiles along the porcine intestinal gut as well as regional differences in the inflammatory response to S. typhimurium infection. Taken together, these data should provide a basis for a complete understanding of the porcine intestinal response to bacterial infection.

Characterisation of basal expression of selected cytokines in the liver, spleen, and respiratory, reproductive and intestinal tract of hens

“…Although the expression of avian cytokines in various tissues of hens has been characterised in many papers over the last few years, most papers reported on comparative experiments targeted at a limited number of tissues (Swaggerty et al, 2004;Withanage et al, 2005;Berndt et al, 2007). Consequently, most of the studies presented only fold inductions, i.e., the ratio between the expression of the cytokine gene in experimental and control groups and cytokine basal expressions in multiple tissues have been character-ised only marginally (Collado-Romero et al, 2010). Whilst the presentation of results in this manner can be useful for particular aspects, it also holds several pitfalls.…”

Immunomodulatory factors and infectious agents associated with the hepatic gene expression of the IGF system in nursery pigs

“…The primers for IL-1β, IL-10, IFN-α and IFN-γ were previously designed by Collado-Romero et al (2010). All other primers were designed by Slifierz et al (2013).…”

Oxygenated Drinking Water Enhances Immune Activity in Pigs and Increases Immune Responses of Pigs during <i>Salmonella</i> Typhimurium Infection

“…The most common clinical signs of infection in pigs are diarrhea and enterocolitis [1]. As growing piglets that recover from illnesses such as diarrhea are often stunted and grow slowly, Salmonella infections in growing piglets cause considerable economic loss to pig farmers [4].…”

“…Relative IL-1β expression level was evaluated using MyiQ TM 2 (Bio-Rad Laboratories, Hercules, CA, U.S.A.) with 0.5 µg of cDNA as template and the iQ TM SYBR ® Green Supermix (Bio-Rad Laboratories). Primer set for IL-1β [5'-GGC CGC CAA GAT ATA ACT GA-3' and 5'-GGA CCT CTG GGT ATG GCT TTC-3' (NM_214055)] and β-actin [5'-CAG GTC ATC ACC ATC GGC AAC G-3' and 5'-GAC AGC ACC GTG TTG GCG TAG AGG T-3' (U07786)] were designed as previously described [4]. The relative quantitative PCR conditions were 5 min at 95°C followed by 45 cycles of 30 sec at 94°C, 30 sec at 57°C and 45 sec at 72°C.…”

“…Total RNA extracted immediately from the cells without LPS stimulation, and the remaining process for quantification of relative mRNA expression level of TNF-α and IFN-γ was performed as described for IL-1β. Primer set for TNF-α [5'-CCT CTT CTC CTT CCT CCT G-3' and 5'-CCT CGG CTT TGA CAT TGG-3' (NM_214022)] and IFN-γ [5'-CAA AGC CAT CAG TGA ACT CAT GA-3' and 5'-TCT CTG GCC TTG GAA CAT AGT CT-3' (X53085)] were designed as previously described [4]. All data are expressed as mean ± standard deviation (SD).…”