Ch 16 Flashcards
innate immunity
defenses against any pathogen
nonspecific
no learning or adaptation
adaptive immunity
resistance to a specific pathogen
innate immunity first line of defense
skin- protects against all microbes
mucous membranes and their secretions- traps microbes
normal microbiota- creates crowded beach
innate immunity second line of defense
phagocytes (neutrophils, eosinophils, dendritic cells, and macrophages) inflammation fever antimicrobial substances complement
process of phagocytosis- 7 steps
- chemotaxis and adherence
- ingestion
- formation of phagosome
- fusion of phagosome and lysosome forms phagolysosome
- digestion of ingested microbes
- form residual body w indigestible material
- discharge of waste materials
6 mechanisms of avoiding destruction by phagocytosis
- inhibit adherence
- kill phagocytes
- lyse phagocytes
- escape phagosome
- prevent phagosome-lysosome fusion
- survive in phagolysosome
6 stages of inflammation
- damaged cells release chemicals
- blood clot forms
- abscess starts to form
- marginization- phagocytes stick to endothelium
- diapedesis- phagcytes squeeze between endothelial cells
- phagocytosis of invading bacteria occurs
cause of fever
gram-negative endotoxins cause phagocytes to release interleukin-1
hypothalamus releases prostoglandins that resets it to a higher temp
body increases rate of metabolism and shivering to raise temp
effects of fever
increases transferrins, IL-1 activity, and produces interferon
complement- classical pathway
uses antibodies to start
goes from C1-C9
complement- alternative pathway
starts at C3
complement- lectin pathway
lectin binds to carbohydrates and activates C2 and C4
complement effects C3b
activates C5 causes opsonization (marks the pathogens)
complement effects C3a and C5a
cause inflammation
complement effects C5b + C6+ C7+ C8+ C9
cause cell lysis
complemtent activation C1-C3
- antigen-antibody complex bind and activate C1
- C1 activates and splits C2 (into C2a and C2b) and C4 (C4a and C4b)
- C3a and C4b combine and activate and split C3 into C3a and C3b -> initiates cytolysis, opsonization, and inflammation
neutrophils
highest concentration of leukocytes
granulocyte
phagocytosis
basophils
granulocyte
produces histamine
eosinophils
granulocyte
produces toxic proteins against parasites
some phagocytosis
monocytes
phagocytosis
matures into macrophages
dendritic cells
derived from monocytes
phagocytosis
initiates adaptive immune response
lymphocytes
natural killer cells
destroy target cells by cytolysis and apoptosis
T cells
cell mediated immunity
B cells
produce antibodies
cytokines
protein that regulates the immune response and may induce fever, pain, or T cell proliferation
perforin
protein that makes a pore in target cell membrane, release by CTLs
interferons
groupm of signaling proteins made and released by host cells in response to the presence of pathogens