Tutoring Flashcards
innate immunity characteristics
rapid, acute, inflammation
some specificity
no memory
adaptive immunity characteristics
slower
highly specific
memory
define antigens
any substance that can induce an immune response
–is not always a protein
define epitope
small portion of ag that binds to ab
define hapten
very small ags/epitopes that do not initiate an immune response
all immunogens are ___ but not all ____ are immunogens
ags–ags
cellular immunity
cell components
innate – phagocytes, DCs, NKs
adaptive — abs, B cells
humoral immunity
blood components
innate — chemokines, cytokines, APPs
adaptive — abs, b cells
how do cells communicate
thru chemokines and cytokines
define cytokines
secreted proteins that regulate many activities
define chemokines
regulate cell migration and mvt via chemotaxis
innate immunity cells
phagocytes
dendritic cells
basophils/eosinophils
mast cells
phagocytes
take up/destroy
also secretory functions
macrophage in tissue
M-CSF stim production
long half life
typically stay in tissue
dendritic cells
ag presenting cells - APCs
help to stim t cells
basophils/eosinophils
associate w/ helminth rxns
parasites
mast cells
allergic rxns
release most inflammatory factors
specificity of AI
ensures that the immune response to a microbe is selective to that microbe
diversity of AI
enables the immune system to respond to a large variety of ags
memory of AI
increases the ability to combat repeat infections by the same microbe
clonal expansion of AI
increases the number of ag-specific lymphocytes to keep pace w/ microbes
specialization of AI
generates responses that are optimal for the defense against dif microbes
contraction and homeostasis of AI
allows the immune system to recover from one response so that it can effectively respond to new ag
nonreactivity to self of AI
prevents injury to the host during responses to foreign ags
clonal selection
happens w/o the ag present
w/o disease state
will make all kinds of lymphocytes even tho there is no disease
occurrence of clonal expansion vs selection
expansion = ag is present
selection = ag not present
occurrence of clonal expansion vs selection
expansion = ag is present
selection = ag not present
active immunity
injected w/ an ag via vaccine
host generates ab and saves as memory
passive immunity
–injecting abs from another host which will clear your infection
–skips first phases of adaptive immune response
–results in no memory
development of lymphocytes begins in fetal _____
liver
lymphocytes use lymph to circulate but cannot enter ?
immunoprivilaged sites
eyes
brain
testes
classic DCs recognize ?
proteins
ags generated in the blood are delivered to ?
spleen
interferons are anti-_____
antiviral
______ are the only thing that can activate a naïve T cell
DCs
homing is mvt of ?
leukocytes from blood to tissue
to fight in response to infection
recirculation is mvt of ?
leukocytes from tissue to blood
in order to look for ags
families of cytokines that regulate mvt of leukocytes differ because ?
of the number of cystines
CCL2/MCP-1
monocyte recruitment
CCL19/MIP-3B
t cell/dc migration in LN
CCL21/SLC
t cell/dc migration in LN
CXCL8
**important
neutrophil recruitment
CXCL10
effector t cell recruitment
CXCL12
naïve b cells to LN
homing
CXCL13
b cell migration to follicles
list steps in transepithelial migration
infection detected activation of endothelium tethering rolling adhesion-stop transmigration
list steps in transendothelial migration
infection detected activation of endothelium tethering rolling adhesion-stop transmigration
post infection detection, leukocytes enter LN via ?
post capillary venules
what cells are the first to detect infection?
neutrophils and monocytes
_________ cells are the first to detect pathogens and are activated in ______ and begin to produce ?
neutrophils and monocytes
in tissues
IL-1 and other cytokines
–used to recruit other cells
________ released during infection/inflammation causes ?
cytokines
activation of endothelium to express selectins on surface
these are not expressed in healthy states
in transendothelial migration what does activation of endothelium mean?
endothelium expresses selectins
types of selectins
P, E, L
p-selectins
on endo
activated by
–histamine, thrombin
ligand – xialyl lewis x bodies
e-selectins
on endo
activated by
—TNF, IL-1
ligand – xialyl lewis x bodies
L-selectins
on leukocytes/lymphocytes
ligand – pNAD on HEV endo
xialyl lewis x bodies are located on ?
on lymphocytes and leukocytes
tethering
selectins are present on endo
bind their respective ligands on passing cells
necessary to slow them down to initiate rolling
rolling of leukocytes is mediated by ?
integrins
mediate adhesion of cells to endo
found on leukocytes
integrins involved in rolling and their respective ligands
LFA1 — ICAM
MAC1 — ICAM
VLA4 — VCAM1
A4B7 — VCAM1, MadCAM1
integrins on leukocytes and no chemokines present, results in ?
weak affinity for endo
chemokines from neutrophils/monocytes in tissue
inside-out signaling
when neutrophils/monocytes release chemokines in response to pathogen presence
this gives integrins on leukocytes high affinity for their ligands on endo in order to migrate
inside-out signaling
when neutrophils/monocytes release chemokines in response to pathogen presence
this gives integrins on leukocytes high affinity for their ligands on endo in order to migrate
naïve leukocytes/lymphocytes have no ______ receptors thus cannot tether/roll/migrate
no chemokine receptors
adhesion and stop —- migration
integrins bind to ligands on endo w/ high affinity
rolling stops
T cells are different
adhesion and stop —- migration of T cells
CD44 on endo—mediates rolling
this mobilizes effector t cells
CD44 binds hyaluronic acid on T cell
significance of CD44 binding hyaluronic acid on T cells
it upregulates the VLA-4/VCAM integrin binding
transmigration into tissue occurs via ______ . discuss this migration
diapedesis
cells slide thru gap junctions to enter tissue using ameboid shapes
once cells migrate into tissue how do they know where to go?
migrate towards sight of infection as directed by the chemokines being released by cells already at the site
naïve cells enter LN via ? and ____-selectins on them to bind ?
via HEV
L-selectins to bind to pNADs on HEV
T cell entrance to LN via HEV
CCR7 on t cell – binds CCL19/21 on HEV
which activates integrins on HEV
when no ag is found, b and t cells return to lymph via ________ and enter other ______ lymph organs, eventually reaching ?
efferent lymph vessel other 2ndary lymph organs thoracic duct ---and then returned to circulation-IVC
when an ag is found, b/t cells are activated and return to ______ where they will then undergo migration into tissue. which is the same for all _______ cells.
circulation
same for all effector/memory b/t cells
t cells bind CXCL10
when an ag is found, b/t cells are activated and return to ______ where they will then undergo migration into tissue. which is the same for all _______ cells.
circulation
same for all effector/memory b/t cells
t cells bind CXCL10
how are b and t cells separated in LN
are attracted to different chemokines present
chemokines for B cells in LN, and other organs
CXCR5 on b cell binds
—–CXCL13 primary follicle
in spleen enter in red pulp and migrate to 13 in white pulp
where mature and return to circulation
chemokines for T cells in LN
CCR7 on t cells binds
—- CCL21 in T cell zone
timeline of activated T cells exit from LN
usually stay in LN for a few days to allow for proliferation
to create an army before going to war
TLR 2,6
peptidoglycan
gram positive bacteria
TLR 4
LPS
gram neg bacteria
endotoxin
TLR 5
flagella
TLR 9
CpG
TLR 3
dsRNA
TLR 7,8
ssRNA
extracellular TLRs
1,2,4,5,6
intracellular TLRs
3,7,8,9
receptor NLR
ligand = intracell proteins
formation of inflammasome and caspase mediated apoptosis
scavenger receptor
ligand = negatively charged bacterial components
not all scavengers have same extracell domain
lectin receptors
ligand = carbs
**eukaryote - terminal sugar is galactose or sialic acid
bacterial/PAMP - terminal sugar is mannose
lectin receptors
ligand = carbs
**eukaryote - terminal sugar is galactose or sialic acid
bacterial/PAMP - terminal sugar is mannose
HMGB1 binds to
RAGE**