Endotoxemia is responsible for severe illness in horses. Individuals can become unresponsive to the endotoxin molecule after an initial exposure; this phenomenon has been called developing a state of "endotoxin tolerance" (ET). ET has been induced in horses in vivo; however, cytokine expression associated with ET has not been investigated. The purpose of this study was to develop and validate a method for inducing ET in equine peripheral blood mononuclear cells (PBMCs) in vitro, and to describe the cytokine profile which is associated with the ET.
Blood was collected from 6 healthy horses and PBMCs were isolated. ET was induced by culturing cells with three concentrations of endotoxin given to induce ET, and evaluated after a second dose of endotoxin given to challenge the cells. The relative mRNA expression of IL-10 and IL-12 was measured by use of quantitative PCR.
ET was induced in all cells (n=6) exposed to the 2-step endotoxin challenge. In PBMCs treated with 1.0 ng/ml of endotoxin followed by challenge with 10 ng/ml of endotoxin, the relative mRNA expression of IL-10 in tolerized cells was not different from positive control cells. In contrast, the relative mRNA expression of IL-12 in tolerized cells was decreased by 15-fold after the second endotoxin challenge compared with positive control cells.
This experiment demonstrated a reliable method for the ex vivo induction of ET in equine PBMCs. A marked suppression of IL-12 production is associated with ET. The production of IL-10 was not altered in ET in our model. / Master of Science
| Identifer | oai:union.ndltd.org:VTETD/oai:vtechworks.lib.vt.edu:10919/44307 |
| Date | 10 September 2010 |
| Creators | Frellstedt, Linda |
| Contributors | Biomedical and Veterinary Sciences, Furr, Martin O., McKenzie, Harold C. III, Barrett, Jennifer G. |
| Publisher | Virginia Tech |
| Source Sets | Virginia Tech Theses and Dissertation |
| Detected Language | English |
| Type | Thesis |
| Format | application/pdf |
| Rights | In Copyright, http://rightsstatements.org/vocab/InC/1.0/ |
| Relation | Frellstedt_L_T_2010.pdf |
Page generated in 0.0026 seconds