Microbiology and Immunology 2500A/B Lecture Notes - Gut Flora, Mucus, Nod2
14 Dec 2012
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Document Summary
Innate immunity is the first line of defense against a pathogen. It is always ready to destroy pathogens and is effective at stopping most at an early stage: active all the time, over 90% of pathogens destroyed this way. Inherited: born with innate immunity (cells and soluble molecules, conserved though evolution. Everyone has same innate immune system (same barriers, cells, soluble molecules) Responds immediately: pathogen usually destroyed before any symptoms. No memory: same immune response to identical pathogen each exposure (non-adaptive) As long as skin is intact it is a very effective barrier. Anti-microbial enzymes = secreted by activated epithelial cells (natural antibiotics) They act to destroy the cell wall of pathogen. First barriers try to block the pathogens entry into tissues. If the pathogen enters the tissue then innate cells and soluble molecules are activated and rapidly eliminate the pathogens that enter.
