Exam 2 Innate Pt 2 Flashcards
can activate Macrophages
cytokines (from WBC) and Active T cells
Direct the attack against persistent infections phagocyes cannot kill
lymphocytes-B or T
Granulomas
Giant-multinucleated balls of macrophages that wall off orgs that cannot be destroyed
Cavitary TB
tubercles in lung-immunocompromised
Miliary TB
in children; many small granulomas
Complement system is made by what organ
liver; circulate in blood and kill 3 ways
Membrane Attack Complex-MAC
kills cells; c5b binds in cell membrane, c6-c9 join to form a pore in the membrane which causes the cell to lyse
MAC involves ___ which embeds in membrane and _____; causing a ____ and cell to lyse
c5b, c6-c9, pore in membrane, lysis
Activation of complement system goal and ways
goal is to activate C3 convertase;
- lectin and classical pathways-c4b2b convertase
- alternate pathways-c3bBb convertase
convertase of lectin and classical
c4b2b
Convertase of alt. pathways
c3bBb
Alt Pathway
c3 is unstable so it spont. breaks down into c3a/c3b; this little bit can bind -NOT opsonize- bacteria and intiate c3bBb convertase
Lectin Pathway
lectins produced in the liver and bind carbs such as mannose–
MBP floats in blood and activates c4b2b
classical pathway
Activates C4b2b;DOES NOT happen with initial exposure; activated by antibodies produced by the adaptive immune system. Antigen-antibody complex activates C1
Activation of complement system that is ONLY with second exposure
Classical pathway requires antibody-antigen complex to activate
c3a and c5a
anaphylaxis (causes histamine to degranulate) and chemoattrictants for phagocytes
activates MAC
c5b
C3b does
opsonization which leads to increased phagocytosis
c5b
activates MAC
CPR
production stimulated by cytokines, opsonize bacteria –> activates C1 –> complement activation; THUS CPR acts as an antibody to activate the classical pathway
C1
activates classical pathway
Induces fever
pyrogens
Endogenous
from own cell (TNF-alpha)
Exogenous
bacterial protein stimulates fever
Mechanism of fever
- chemicals secreted by phagocytes travel to hypothalamus
- hypothalamus secretes prostaglandin –> resets thermostat
- nerve impulses cause shivering, vasodilation, and increased metabolic rates –> in
causes reset of thermostat
Prostglandin
Benefits of fever
inhibit growth, speeds up phagocytosis and repair of tissue, increases leukocyte motility, reduces Fe available
Complement effects on viral infections
NONE-thus MAC does not either
Interferon alpha and beta
- cell is infected and produces dsRNA
- cell produces type one IFN in response
- IFN alpha and beta secreated to other cells
- IFN turns on IVAP inactive
- once virus infects the cell it activates IVAP causing apoptosis
IFN also activates NK cells
Natural Killer Cells branch of immune system
adaptive lymphocyte; only one; really funtions in innate (non specific)
only lymphocyte that is adaptive
NK cells
Activates NK cells
IL-12,Type 1 INF, and TNF-alpha
Progenitor cell of NK cells
lymphoid progenitor
what do NK cells attack
intracellularly infected and cancer cells-Fc receptor binds IgG which has opsonized PAMP
Receptor on NK cells
Fc receptor which binds IgG which has opsonized
How NK cells kill
release perforin and then granzyme –> apoptosis
perforin
released by NK cells; allows granzymes to enter
Granzyme
released by NK cells; follow up perforin in apoptosis
Cytokine Production by NK cells
IFN gamma (type 2) which will stimulate/activate macrophages and maturation of dendritic cells –> cause T cell response
IFN gamma (type 2)
secreted by NK cells; stimulates/activates macrophages and maturation of dendritic cells –> cause T cell response
NK cell response cessation
when adaptive kicks in
