innate_immunity
innate immunity
introduction
innate immunity is a term used to refer to all types of immunity excluding
acquired_immunity (acquired immunity relies upon immune cells such as T-cell and B-cell lymphocytes which produce antibodies and these immune systems arose late in evolution, appearing in vertebrates), and thus is relatively non-specific
innate immune system
anatomical barriers
intact skin and mucosa
desquamation helps remove bacteria
irrigation helps remove organisms
mucus forms a barrier, traps organisms and allows their expulsion
commensal organisms form a normal flora which helps prevent colonisation by more pathogenic flora
mucus
an important part of innate immunity is mucus production which forms a barrier to invading organisms
mucus consists of mucins which are glycan sugars and recently, it has been discovered a symbiotic relationship exists whereby certain strains of bacteriophage viruses bind to the mucins and reduce binding of bacteria to the mucin by over 10,000 fold, thereby further reducing bacterial invasion.
the inflammatory response
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cells involved include:
mechanisms utilise histamine, cytokines, chemokines, etc
phagocytosis of cells is important for intracellular virus or bacterial infections, and xtracellular bacteria and protozoa, but not useful for fungi or intracellular protozoa
coagulation may play a role
some bacteria once inside a macrophage can release toxins to stop the functioning of mitochondria and this then triggers the cell to undergo apoptosis
1)
complement system
innate_immunity.txt · Last modified: 2020/08/23 12:11 by gary1