Flashcards in 48-Cytokines Deck (44)
What is a cytokine?
proteins released by cells that participate in the immune response
How is cytokine expressed?
released extracellularly or expressed on surface of the cell
How are cytokines recognized?
unique receptors in surface of immune cells. activation of receptor results in changes in the function
what are the functions of cytokines in the immune response?
antiviral response (interferons)
immune cell activation
how do cytokines act?
autocrine, paracrine, endocrine
what is pleiotropy?
a single cytokine has more than 1 function depending on the cell it targets
B cell-activation, proliferation, differentiation
what is redundancy?
cytokines have the same action
IL2, 4, 5 do proliferation
what is synergy?
cytokines act together for a response
IL4 and 5 induce class switch to IgE
what is antagonism?
cytokines inhibit one another
Il4 and IFNy block class switch to IgE
How is a cell fate decided?
cells integrate signals from many cytokines
what are the phases of sepsis?
cytokine storm and immune suppression?
what is the cytokine storm?
1st phase in sepsis, driven by release of inflammatory cytokines
what is the immune suppression in sepsis?
2nd phase, days to weeks after onset, immunosuppressive cytokines released. this phase is resolved with elimination of infection or death
cytokine treatments for sepsis
most have failed. have not shown and increase in survival and have worsened death
what are the 7 cytokine families
growth factory family
how are the cytokine families delineated
by their receptor which have distinct signaling pathway. signaling pathway defines the treatment for cytokine
Growth factor family receptor
tyrosine kinase domains
growth factor family action
increased tyrosine phosphorylation signaling, immune cell differentiation
serine/threonine kinase domains, tetramerization of 2 type 1 and 2 type 2 for phosphorylation of SMAD proteins
inhibit immune cell function, t cell differentiation, antibody production, promote tissue repair
IL-1 Family receptor
TIR domain, binding of MyD88
IL-1 family action
MyD88 induces downstream signaling to activation NF-kB for inflammation
What does IL-1Ra do?
TNF family receptor
TRAF and TRADD
TNF family action
TRAF is inflammatory
TRADD does apoptosis
What does TNF alpha and TNFR1 (receptor) do?
part of TNF family that can be inflammatory or do apoptosis
IL-17 Family receptor
TLR and TNF
IL-17 family action
dimerization and bind ACT1 which interacts with TRAF for inflammation
Chemokine family receptor
7 transmembrane g protein coupled receptor