Interferons Flashcards
What are the three types of interferons?
Type 1 = alpha or beta
Type 2 = gamma
Type 3 = lambda
State three functions of IFN alpha or beta
Activation of adaptive immune response
Modulation of innate immune response (promotes Ag presentation and promotes NK cells)
Induces antimicrobial state in infected and neighbouring cells
How do type 1 interferons modulate the innate immune response?
Promotes Ag presentation
Promotes NK cells
Which cells produce IFN gamma?
Activated T cells
Activated NK cells
Which receptor does IFN gamma bind to?
IFN gamma receptor
Which tissues are an important target of type 3 interferons?
IFN lambda are important on epithelial surfaces
Which receptors do IFN lambda signal though and where are these found?
IL 28 receptor
IL 10 beta
Present on epithelial surfaces
Which receptor does IFN beta bind to?
IFN alpha receptor
Which cells release IFN beta?
Infected cells
Fibroblasts
Which cells produce IFN alpha and which transcription factor is constitutively expressed in these cells?
Plasmacytoid dendritic cells
IRF-7
Which type 1 interferon has 13-14 isotypes?
IFN ALPHA
List three pattern recognition receptors
RIG-1/mda5
TLR
cGAS
What does RIG-1 recognise?
RNA lacking CAP
What do TLR recognise?
RNA in endosomes
What activates the cGAS enyzme?
Cytoplasmic double stranded DNA
Upon recognition of RNA which lacks CAP, what does RIG-1 bind to and activate?
RIG-1 binds to mavs
What is the downstream effect of RIG-1 binding to mavs?
Activated mavs phosphorylates Irf3
What does phosphorylated Irf3 do?
Irf3 dimerises and translocates to the nucleus, where it acts as a transcription factor for IFN-beta
Which RNA pattern recognition receptor pathway joins up with the IRF-3 pathway?
TLR3
What are the main two TLR in the endosomes?
TLR3
TLR7/8
What is the downstream effect of TLR 3 activation?
Phosphorylation of IRF3, dimerization, translocation to the nucleus, and transcription of IFN-beta
Which of the TLR pathways is unique to the plasma cytoid dendritic cells?
TLR7/8 pathway
What downstream molecule do activated TLR7/8 signal via?
TLR7/8 signal via myd88