Innate immunity against infectious diseases, particularly in swine

Abstract

The importance of innate defense mechanisms especially refering to swine, was characterized. Physical, chemical and microbial barriers were mentioned. The role of cells was underlined in controlling infection by phagocytosis without earlier immunisation by antigens and only depending on the genome of the born animal. The two main types of phagocytic cells were evaluated in antiinfectious activity: a)granular leucocytes, including neutrophils, basophils, eosynophils and mast cells, b)mononuclear phagocytes. These include blood circulating monocytes and macrophages. It was stated that natural killer cells belonging also to innate immune system can kill bacteria and viruses participating as etiologic agents in infectious diseases. Another group of innate immune factors, not cells but molecules, are creating defensins being host defense peptides. The complement mediates the inflammatory response, controlling bacterial infections. The following antiinfectious activity is exerted by Toll-like receptors. The presented cytokines are protein or glycoprotein molecules secreted by cells. They participate in intercellular and intracellular signalling.