Submitted to: Journal of Leukocyte Biology
Publication Type: Abstract Only
Publication Acceptance Date: 8/30/2006
Publication Date: 11/9/2006
Citation: Eicher, S.D., Williams, J., Patterson, J., Minton, E., Marchant Forde, J.N. 2006. Mucosal immune response to a prolonged stressor in pigs. Journal of Leukocyte Biology. 80(1):40.
Technical Abstract: Stress responses to transportation are common in species used in research and alter immune responses. The ileocecal area of the intestine is rich with immune cells, while the jejunum is more sparsely populated. However, the epithelial cells also contain toll-like receptors (TLRs), that recognize pathogens, as well as the resident immune cells in both areas. Our objective was to determine if a rest stop would be beneficial to swine mucosal immunity during a prolonged transport. Rested pigs were transported for 8 h, rested with food and water for 8 h, then transported an additional 8 h. Stressed pigs were continuously transported for 16 h. Sections of the ileum (adjacent to the ileocecal junction) and from the jejunum were used for quantitative RT-PCR analysis of mRNA expression of the chemokine that causes an antigen presenting cell to move to an area (CCL20), and interleukin (IL)-8 (which cause white blood cells to move to infected areas), toll-like receptors 2, 4, and 5 (which recognize pathogens), and anti-microbial peptide, PR39 (which recruits phagocytic cells to infected and inflamed areas on d 0, 1, 3, 7, and 14 following transport. The stressed group tended (P = 0.07) to have greater IL-8 expression in the jejunum on d 1. In contrast, ileal CCL20 and TLR5 were only different (P < 0.05) between the treatments on d 14, caused by increased expression in the stressed group. PR39 was greater (P = 0.01) for the rested group on d 3 in jejunum tissue. Analysis revealed a day effect (P < 0.05) for IL-8 and PR39 in the ileum and TLR4 and TLR5 in the jejunum, with greatest expression on d 3. CCL20 expression in the jejunum had a day effect, and was greatest (P < 0.01) on d 7. TLR2 did not change in either tissue. The day effects indicated that a stress was imposed in both treatments. However, including a rest period during the stressor allowed some beneficial early immune responses throughout the trial period. This work is a useful component of the overall picture used to establish transport practices.