L13 Innate Immunity Flashcards
What is innate immunity
Immediate response to a pathogen that does not confer long lasting protective immunity.
Non specific defense system
What Are the 3 phases of response to initial infection
Innate immunity(0-4 hrs)
Early induced innate response(4-96hrs)
Adaptive immune response(>96 hrs)
What are innate immune mechanisms
Act immediately
Followed by early induced responses which can be activated by infection but do not generate lasting protective immunity
When would adaptive immunity occur
Only if an infectious organism can breach these lines of defense will an adaptative immune response ensue with the generation of antigen specific effector cells that specifically target the pathogen and memory cells that can prevent reinfection with the same microorganism
What are the cells of innate immunity
Neutrophils Monocytes Natural killer cells Eosinophils Basophils
First responders to infection and phagocytose bacteria in to phagosomes before hydrolyzing and destroying them
Neutrophils
Rapid response and not prolonged effect
Neutrophils
Phagocytose pathogens
Macrophages
When do monocytes become macrophages
When they are in tissues
Provide prolonged defense
Monocytes
What are natural killer cells and what do they do
Large granular lymphocytes that recognize non specifically the surface changes on tumor cells and virus infected cells and damage these cells without prior sensitization
Cells that fail to express MHC class 1 molecules
Natural killer cells
What is the process of ADCC and which cell carries it out
Natural killer cell
Binding to antibody already attached to antigen on a target cell using their Fc receptors
Naturally present in spleen and peripheral blood
Natural killer cells
Have granules containing a variety of enzymes and toxic proteins which are released when these cells are activated
Eosinophils and basophils