Antibody mediated inflammation Flashcards
What does the AID enzyme do?
Allow VDJ somatic hyper-mutation
What is a class switch recombination?
Class switch recombination occurs by deletion of the DNA that encodes a specific type of Fc so another type of Fc can be transcribed and translated (e.g. cut out the default IgM/IgD so that the succeeding locus for IgG can be transcribed)
What is an antibody feedback by inhibitory Fc Receptor (FcR)?
It is a way to regulate antibody response
When an antibody-antigen complex binds to a B-cell’s Ig => it will bind to the Fc receptor, this will inhibit B-cell response
This is to avoid remaking an antibody from scratch when the body already has antibodies for the antigen
What happens if the inhibitory receptor is defected?
B-cells will produce non-stop antibodies
What is the particularity of Fc∂R2 receptors?
Fc∂R2A sends an activating signal
Fc∂R2B sends an inhibitory signal
What are immune complex formations?
Several antibodies can bind to a same pathogen => this forms an immune complex formation, it creates several Fc domains sticking out
Many Fc domains have low affinity, but immune complex formations create a stronger signal
What are the 3 pathways of activation for the complement system?
- alternative pathway
- classical pathway
- lectin pathway
=> all pathways converge in formation of C3 convertase
What is a membrane attack complex (MAC)
Complex going through the membrane of a pathogen and killing it (cell lysis)
In the complement system, what is the use of C5 when cleaved?
C5a generates inflammation
C5b generates MAC (with other complements)
Why is Fc∂R polymorphism important?
Depending on the polymorphism, it can be more or less effective for cell death (important to take into considerations when creating antibody drugs specialized to the patient’s genome)
