Study your flashcards anywhere!

Download the official Cram app for free >

  • Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off
Reading...
Front

How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key

image

Play button

image

Play button

image

Progress

1/32

Click to flip

32 Cards in this Set

  • Front
  • Back
CTLA-4 and B& on APC

function
dysfunction
competes with B7 for binding to CD28 which is on Thelper cells.

B7 activates
CTLA-4 inactivates.
explain costimulatory signal
Bcells express B7 which binds to Thelper cells CD28 and activates a cell signalling cascade inside the Tcells.
THIS IS SIGNAL NUMBER 2 for TCell activation
why would a Tcell go into anergy?
if it recieved the signal #1 of antigen binding to the TCR, but did NOT recieve the costimulatory signal of B7 binding to CD28
Th1 population responsible for
cell-mediated functions like delayed type hypersensitivity, activating CD8+ TC cells
what do Th1 cells secrete?
(cytokines)
IL-2, IFN-gamma, and TNF-beta
what do Th2 cells secrete?
(cytokines)
IL4,
what do the Th2 cytokines activate?
bcells and humoral response

IL4
what two cytokines have a systemic effect, and through what type of signalling
endocrine signalling; TNF and IL-1
WHAT is the effect of systemic cytokines, which are they
fever, inflammation, induction of acute phase proteins; TNF alpha and IL-1
function of IL-4
forms IgE by affecting DNA looping in gene expression

enhances mast cell proliferation
INF-gamma function
increase expression of MHC 1 and 2


interferon by the way
4 classes of cytokines in alphabetical order:
Chemokines
HEmatopoietic
Interferons
Tumor necrosis factor
function of chemokines
acctract cells to inflammatory site; leukocyte trafficking
function of hematopoietins
3 example cells
blood cell production/regulation of amounts; erythropoietin, IL-2 and CSF (colony stim factor)
function of IL-2, what type of cytokine it is
hematopoietic; produced by Thelpers when interacting with APC; signal #3 for Bcells
Function of Il-4, what type of cytokine it is;
hematopoietic; promotes class switching to IgE - allergy, mast cells, basophils
function of CSF, what type of ctokine
hematopoietic; determines myeloid or lymphoid progenitor pathway
all interferons are:
ANTIVIRAL; respond to virus infection by encouraging MHC 1 and 2 expression; enhance degrading of viral material, activate NK and Tc cells (alpha/beta)
function of TNF cytokines
similar to fas, they induce cell death - have a SYSTEMIC EFFECT (along with IL-1)
how do molecules antagonize cytokines?
by mimicking the actual cytokines and binding to their receptors so the cytokines cant;

by mimicking the receptors of cytokines so the cytokines bind to the wrong thing.
All Th2 cytokines are:
INTERLUEKINS!!! IL IL IL IL IL IL

except for GM-CSF
Th1 subset particularly suited to:
viral infections
intracellular antigens/pathogens
which interleukin is essential for generation of Th2 response?
IL-4
WHAT IS crossregulation of cytokines?
each subset inhibits the development of the other; thus the critical molecules that start development down a particular pathway (IL4 and INF-gamma)
which is better, tuberculoid or lepromatous leprosy?
tuberculoid; a cell-mediated immune response can take place because the Th1 cytokine population is increased. in lepramatous, Th2 are there and antibodies are not antiviral like cell-mediated Tkilling cells
what type of cytokine-related disease results from ENDOTOXINS
endotoxins from bacteria cell wall

SEPTIC SHOCK from systemic overproduction of TNF alpha and IL-1
2 primary producers of cytokines
macrophages
Thelper cells
how cytokines modulate/enhance
-Innate immunity
-Adaptive immunity
innate: chemokines attract cells to inflammatory site; ENHANCED VASODILATION

adaptive: activate b or t cells; modulate blood cell population
what is a cytokine?
a small protein that communicates effects in the immune response
what are 5 attributes of cytokines?
pleiotropy
synergy
antagonism
redundancy
cascade induction
what are the 2 subunits of a cytokine receptor?
-ligand binding subunit
-signal transducing subunit
what is an example of cytokine receptor?
IL-2Receptor; has alpha, beta, and gamma subunits;

gamma/beta are constitutive, but alpha only expressed on Ag-activated Tcells. result: high-affinity binding of cytokine IL-2 only when needed.