Innate Immunity Flashcards
Immediate innate immune response time frame
0-4 hrs
*can have removal of infectious agents with no symptoms of infection
Early induced innate immune response time frame
4-96 hrs
*recognition of PAMPS, inflammation
Adaptive immune response time
greater than 96 hrs
*transport of Ag to lymphoid organs
Physical barriers
skin, mucus membranes
Humoral barriers
Complement system
Cellular barriers
Phagocytes, NK cells
Skin, cilia in respiratory tract, peristalsis in GI tract, washing by tears/saliva, and thick mucus are all types of _______ defense
Mechanical
Chemical factors in the innate immune response
Fatty acids (sweat)
lysozyme and phospholipase (tears/saliva)
low pH (sweat/gastric fluids)
Surfactants (lungs)
Normal flora on the skin and GI tract is an example of what type of defense?
Microbiological
Toxic oxygen-derived products involved in protecting the host during pathogen elimination
Superoxide O2- H2O2 O2 hydroxyl radical OH+ hypohalite OCl-
Toxic nitrogen oxides involved in protecting the host during pathogen elimination
Nitric oxide NO
Antimicrobial peptides involved in protecting the host during pathogen elimination
Defensins
Cationic proteins
Beta-lysine produced by platelets has bactericidal effects against ______ during coagulation
Gram + bacteria
Role of lactoferin and transferin
Bind Fe++ so bacteria can’t grow
Role of lysozyme
digests bacterial cell wall
Role of interferons
inhibit infection and replication of VIRUSES
Role of interleukin 1
increase temperature during inflammation and induce acute phase proteins (bactericidal)
PMN cells that phagocytose microorganisms
neutrophils
Phagocytic cells that ingest microorganisms and infected cells, and can act as Ag presenting cells
macrophages
Role of NK and LAK cells
kill infected or tumor cells
Cells that participate in eliminating parasites
eosinophils
What are the 4 most important cell types in innate immunity?
Neutrophils
Macrophages
Dendritic cells
Natural Killer cells
2 types of granules neutrophils have that are required for the intracellular killing process?
Azurophilic and Secondary
Azurophilic granules in neutrophils contain…
Defensins - kill bacteria
Enzymes - elastase and cathepsin G - degrade bacterial proteins
Lysozyme - degrades bacterial cell wall
Myeloperoxidase - generation of bactericidal subst.
Secondary granules are only found in mature neutrophils and contain…
Lysozyme
Lactoferin
NADPH oxidase - production of toxic radicals
Expression of CD14, CD11b or F4/80 is used to identify what cell?
Macrophages
Macrophages contain _____ that kill intracellular pathogens
lysosomes