cytokines Flashcards
what are cytokines?
small proteins or glycoproteins which act via specific receptors
what are the names of cytokines in general?
interleukins
except TNFa and IFNy
what are the characteristics of cytokines?
pleiotrophy
redundancy
synergy
antagonism
what is pleiotrophy?
cytokine can have multiple effects
what is redundancy?
more than one cytokine carries out the same function
what is synergy?
cytokines work together
what is antagonism?
cytokines work in opposition to each other
what are chemokines?
a subgroup of cytokines involved in cell movement
how do chemokines help with cell movement?
migration along the chemokine concentration gradient provides directional movement
name some inflammatory cytokines?
IL-1, TNFa and IL-6
name some anti-inflammatory cytokines?
IL-10, TGF-beta
what is acute inflammation?
when cytokines rapidly recruit immune cells to the site of infection
how are cytokines are chemokines released in acute inflammation?
macrophages have toll-like receptors which detect pamps. causes them to secrete cytokines and chemokines
what cytokines are secreted in acute inflammation?
TNFa
what chemokines are secreted in acute inflammation?
IL-8
what do chemokines do in acute inflammation?
activate adhesion molecules to increase binding
describe the steps of leukocyte recruitment?
tethering - cytokines make lining of blood vessels more sticky
rolling and activation - chemokines activate adhesion molecules
arrest
diapedesis and migration - move into the tissues
what does TNFa do in immune cell recruitment?
increases expression of adhesion molecules to make the endothelium stickier.
which cytokines are released when T cells are activated?
IL2
what does IL-10 do?
keeps the gut healthy
what happens to people with mutations in their IL-10 receptor genes?
they have severe gut inflammation
what does a controlled release of TNFa do?
fever
acute phase proteins
immune cell production
local inflammation
what happens in sepsis?
overstimulation of cytokines and septic shock
explain the feedback loop that leads to a cytokine storm
immune cells produce cytokines
cytokines stimulate immune cell
immune cell produces more cytokines
