Gastrointestinal immunology: Basic principles and factors that impact immune development an function?

摘要

The gastrointestinal (GI) immune system constitutes the largest immune compartment in the body and plays diverse roles in gut and systemic health. The GI immune system, which includes gut epithelial and immune cells, provides a first line of defense against to the massive amount of potentially deadly microorganisms and toxins residing within the intestinal lumen. The GI immune system must be able to mount a rapid and robust immune response in response to an infectious challenge or breach in epithelial barrier function while at the same time limit its activation in response to common feed antigens and commensal microorganisms. The GI immune system also becomes highly activated during the stress response which may serve as a critical defense mechanismbut if not controlled may impair performance and increase disease susceptibility. Furthetmore, GI inflammatory disorders are often co morbid with diseases in distant organs such as the brain, bone, and respiratory system demonstrating that the state ofthe GI immune system health can impact systemic immune and organ function. The objective of this paper is to provide a broad overview of the anatomy and mechanisms of GI immune function. A specific area of emphasis here will be on postnatal development of the GI immune system in the pig and how early life stressors such as weaning can impact GI immune development and pig health across the production lifespan.