Chapter 8 Flashcards
T cells are activated in the?
lymph node
what happens at the site of infection
DC cells phagocytose microbes and present them on MHC class I and class II and travel through lymphatic vessels to secondary lymph organs
what happens after DC and microbes travel through the lymphatic vessels?
DC enter and interact with T cells looking for a match and if there is a match it initiates adaptive immunity
once adaptive immunity is initiated what happens
the DC is going to bind to the T cell and teach the T cell how to fight infection
if the infection location is in the tissue and skin what secondary lymph organ does it go too
draining L.N
if the infection location is in the blood what secondary lymph organ does it go too
spleen
if the infection location is in the mucosa what secondary lymph organ does it go too
MALT
steps after you step on a nail
- DCs pick up microbes
- DC travels to draining L.N
- in the L.N DC interacts w/ T cells and activate other T cells
receptor-mediated endocytosis of bacteria and microbes that replicate extracellular is what MHC class and T cell
Class II
CD4
macropinocytosis of bacteria or viruses and extracellular infection is what MHC class and T cell
Class II
CD4
viral infection or infection of DC by virus is what MHC class and T cell
Class I
CD8
cross-presentation or no infection virus endocytosed of exogenous viral antigens is what MHC class and T cell
Class I
CD8
T cell recirculate between the
blood and lymph
when T cell recirculate between the blood and lymph the T cell enters via? and interact with DC via?
enter via HEV
interact with DC via MHC
once the T cell enters via HEV and interacts with the DC via MHC what two things could it do?
A. recognize Ag and stay
B. not recognize Ag and leave via efferent lymph vessel
what is extravasation?
T cells leaving the blood stream
how do T cells cross HEV to get into the lymph node
- there is loose adhesion
- there are chemokine signals and increase the strong adhesion molecules
- this tightly bind to endothelial cells
- diapedesis making the it squeeze between endothelial cells
T cell : L- selectin
name HEV
name DC
if both or one
HEV: SL^x+ CD34/ glycam
DC: none
T cell: LFA-1
name HEV
name DC
if both or one
HEV: ICAM2
DC: none
T cell: ICAM3
name HEV
name DC
if both or one
HEV: none
DC: LFA-1 or DC-Sign
T cell: CD2
name HEV
name DC
if both or one
HEV: none
DC: LFA3
L- selectin, LFA-1, ICAM3, and CD2 are what type of molecules
adhesion
Naive cells are before or after encounter Ag
before encountering Ag
activated cells are before or after encountering Ag
after encountering Ag
how do cells keep recirculating?
through the S1P gradient
what is the S1P gradient?
lipids on cells in L.N with a higher concentration on cells that are closer to the efferent lymphatic vessel
when cells become activated what do they bind too?
bind to MHC and peptide on dendritic cell and gets signals to down regulate S1PR (CD19) on surface and upregulate adhesion to DCs
DC=
teacher for the T cells
T cells express S1PR which bind
S1P
T cells need how many signals from DC for activation
2
what is signal one for DC activation
TCR+ coreceptor interact with MHC
what is signal two for DC activation
co-stimulation
CD28 (T cell) interacts with B7 (DC)
what are two major T cell synapse components
adhesion and signaling
p-SMAC is central or peripheral
peripheral