chapter 8 immunology test 4

CD8 functions

tell cells to die and activate macrophages

5 effector CD4 t cells

Th1, Th2, Th17, Tregs, and T follicular helpers

what do T follicular helpers do

activate B cells. found in follicles

what do Th1 make

Interferon gammas, activate macrophages AND B cells ( to make antibodies)

what do Th2s do

activate B cells. IL-4 helps make IgE

IL-5

recruits eosinophilsT

what do Th17s do

secrete IL-17. recruit neutrophils

when does a CD4 become a Th1

primary adaptive immune response

which cell types use MHCI and MHCII

dendritic cells, macrophages, and B cells

dendritic cells are special bc (3 reasons)

migratory

use mhc1 and mhc2

have highest concentration of B7

what is B7

co stimulatory molecule that is needed for the activation of naive T cells

when is B7 made

when PRRs engage PAMPs

final signal for T cell to be activated

B7 binding to CD28

where does a naive T cell find antigen to be activated by

secondary lymphoid tissue → lymph node → DENDRITIC CELLS!!!!

what does CCL18 do

directs naive T cells to mature dendritic cells

4 steps of extraversion

1. rolling adhesion

2. tight binding

3. diadpedesis

4. migration

what do selectins do

bind carbohydrates. L-selectin

what do vascular addresins do

contain carbohydrates to which selectins bind

which are the vascular addresins

CD34, GlyCAM-1, MADCAM-1

what are integrins

typically bind to Ig superfamily proteins. LFA-1

Ig superfamily

ICAM-1

DC-SIGN is a mature dendritic cell marker that binds to…

ICAM-3

immature dendritic cell marker

DEC205

S1P has the highest concentration in

efferent lymphatics

S1PRs are found on

B and T cells - lymphocytes

what is S1P classified as

a chemoattractant

B7 expression is a direct consequence of what

infection!

CD28 is located where?

surface of a naive T cell

CTLA-4

binds to B7. has high affinity and slows down activation as well as limiting cell proliferaiton

who can make B7

macrophages, B cells, dendritic cells

where can you find macrphages in the lymph node

everywhere

where can you fid B cells in the lymph node

the follicle

where are dendritic cells in the lymph node

T cell areas

what is the langerhans cell of the skin

typical immature dendritic cell

langerhans have what on their surface

DEC205

another name for mature dendritic cells

interdigitating dendritic cells

CD4 cytoplasmic tails contain sequences called

immunoreceptor tyrosine-based activation motifs (ITAMs)

what do ITAMs do

they associate with cytoplasmic protein tyrosine kinases

ZAP70 binds to..

zeta chain and then goes thorugh phosphorylation

what are the 3 transcription factors that help with proliferation and differentaition of effector T cells

NFkB, NFAT, and AP-1

IL-2 is produced by the naive T cell and..

that same cell bidns to the IL-2 it made and it will drive proliferation

in TH1 cells, which cytokines induce differentiation

interferon gamma and IL-12

what is the defining transcription factor for TH1 cells

T-bet

what is the characteristic cytokine for TH-1 cells

interferon gamma

function of TH-1 cell

activates macrophages

for TH-2 cells, which cytokine induces differentiation

IL-4

what is the defining transcription factor for TH-2 cells

GATA3

what are the characteristic cytokines of TH-2 cells

IL-4 and IL-5

function of TH-2 cells

activate cellular and antibody response to parasites

characteristic cytokine of TH-17 cells

IL-17

For Treg cells, which cytokine induces differentiation

TGF-beta

defining transcription factor for Treg cells

FoxP3

characteristic cytokines for Treg cells

TGF-beta and IL-10

function of Treg cells

suppress other effector T cells

definining transcription factor for TH-17 cells

R0R gamma T

function of TH-17 cells

recruit neutrophils to enhance inflammation response

defining transcription factor of T follicular helpers

BCl-6

3 cytokines secreted by TH-1 cells

interferon gamma, GM-CSF, and TNF-alpha

for CD8 T cells, what are the 3 cytokines secreted

interferon gamma, LT, and IL-2

for CD8 cells, what are the 3 cytotoxins

perforin, granzymes, granulolysin, serglycin

T follicular helpers also make CXCR5 which binds to

CXCL13

nautral Treg

nTreg - differentiates in the thymus

induced Treg

Treg - differentiates in the periphery

when do T cells no longer need B7-CD28

when they become effector or memory cells

effector T cells express more adhesion molecules (CD2 and LFA-1) than naive T cells by how many times?

2-4 times

VLA-4

an integrin that is a homing receptor for vascular endothelium at sites of inflammation. this binds to VCAM-1 in effector cellsss

cytokine signaling pathway way to remember

“JAKs and STATs”

JAKs stands for

Janus kinases

STATs stands for

Signal Transducers and Activators of Transcriptoin

JAKs and STATs signaling process

1. cytokine receptor subunits bind JAKs

2. cutokine binding assembles the receptor

3. STATs bind to phosphorylated receptor and are then phosphorylated

   1. phosphorlyated STAT dimers enter the nucleus to initiate gene expression

does JAKs and STATs play a role in tcr signaling

yes

what does rearranging the cytoskeleton do (lytic granules)

we can guarantee a high enough concentration of cytokines for CD4 T cells to get the job done

necrosis

death due to physical or chemical injury in which cells lyse or disintergrate

difference between necrosis and apoptosis

in apoptosis, when the cells die, they shirvel or shrink but everything stays intact

time course of programmed cell death

1. contact is made with target cell and granules are distant from the point of contact

2. after 1 minute, granules have begun to move toward the target cell

   1. after 3 minutes, granules are almost ready to be released

what are the 2 pathways that T cells induce apoptosis by

1 is initiated by cytotoxins and the other by interactions with cell surface molecules

which are the cell surface molecules in that other pathway that help T cells induce apoptosis

perforin, granulysin, serglycin

what does perforin do

directs other cytotoxins into cytoplasm of infected host cell

granulysin does what

has antimicrobial acitvity and can activate apoptosis

serglycin

scaffold for other cytotoxins

what do granzymes do

they activate apoptosis by activating caspases in host cell → cascade ending in apoptosis

where is CD40 ligand at

T cell surface

cognate interactions

For a B cell to receive T cell help, both cells must recognize the same antigen