the different Ig classes Flashcards
what state is IgG in? (Monomeric etc)
monomeric
how many igg subclasses, which are most active?
4 Igg1 and igg3 bc of long hinge
what does igg fc region activate, whcih cells have an fcrg
activates complement (phag) and antibody-dependent cell mediated cytotoxicity (NK binds IgG on cell and releases granules --> apop infected cell) on phagocytes and nks
what feature of igg makes it unique?
crosses placenta and binds fcrn
in which situation is igg most useful in?
secondary infection and memory response
what state is igm in?
pentameric
what feature is unique to igm and ige?
functional hinge constant region
what function does igm have?
agglutinates pathogen
activates complement
important in primary ab responses
what state is iga in?
monomeric in serum and dimeric in secretions
how many subclasses? what distinguishes them?
2 subclasses iga1 susceptible to cleaveage by bac proteins, iga2 susceptible to endogenous proteins
what is iga useful for?
passive role in immunisation due to high valency - agglutinates pathogen and opsonising action
why is it good that iga isnt an activator of complement?
wouldnt want inflamm at mucosal surfaces
which cells bind fcra?
phagocytes (monomeric form)
what feature of dimeric iga makes it unique?
secretory component and j-chain
what state is igd found in?
monomeric
