Pre-Programming of the Immune System to Enhance Immunological Capacity of Offspring

Livestock experience different forms of immune system stimulation (ISS) during their production cycle including microbial infection, vaccination, and tissue trauma. The release of pro-inflammatory cytokines during ISS activates the hypothalamic-pituitary-adrenal (HPA) axis or “stress axis”, which regulates metabolism and the immune response during ISS to restore physiological homeostasis. When ISS occurs during pregnancy, it can later programming of the immature fetal neuroendocrine-immune system. It is hypothesized that this plasticity in neuroendocrine-immune programming allows the fetus to adapt to its post-natal environment; however, risk of adulthood disease may also increase if the newborn is not appropriately matched to its novel environment. Bacterial lipopolysaccharide (LPS) endotoxin is an ISS that is commonly used by immunologists to simulate and study the host response to bacterial infection. When LPS was administered to sheep and pigs during late pregnancy, and the dams were consuming diets containing different n3 and n6 polyunsaturated fatty acid (PUFA) profiles, we observed long-term changes to various offspring health-related phenotypes. This presentation will highlight the immunological changes that were observed, and the health implications of these changes will be discussed.