6.2 Flashcards
negative regulators of B cells
some B10 b cells in the spleen secrete il10 that shuts down inflamatory responses
neg signalling through CD22 OR FCYRIIB shuts down BCR
leads to most newly generated B cells to die
how does neg signalling through CD22 OR FCYRIIB shuts down BCR work
contains ITIMs
-phosphorylatin recruits SHP1 tyr phosphotase
-CD22 binds on other cells and signals the same time as BCR
-FCYIIR binds immune complexs
what happens in a TI reponse
generate IgM and no class swithcing
no memory
this always happens
TI-1 ag
bact cell wall components bind to PRR on BCR
TI-2 ag
bind to complement receptors and BCR
what adjuvant is used in humans
aluminum potassium sulfate
what is required to stimualte a strong immune respones
repeated exposure to ag
intranasal route
MALT
may cause alleric repsonse
good for respirator virus vaccine
gastrointestinal route
GALT
may induce TOLERANCE
intravenous
spleen
subcutaneous
lymph nodes
STRONGEST RESPONSE
too little vs excess antigen dose
too little fails to activate enough lymphocytes
to much renders cells tolerant and unresponseive bc they think its self antigen
hole in repitoire
individual lacks genetic info to make T or B lymph of particular specificity
isotypic determinants
different types of antibodies
allotypic determinants
different strains of the same type of antibody
same isotype
idiotypic determinant
afainst different epitope
degradability of Ags
proteins are very degradable- make good immunogens
T cells must be able to degraded ags into 4-10 aa length
hapten complexity
one epitope
many polysacchaides or homopolymers complexity
many epitopes of SAME specificity
proteins complexity
many epitopes of diff specificities
how does molecular weight affect immunogenecity
small subtances not very immunogenic
large over 6k Da are
haptens are low molecules weight so they are coupled to carrier
list some requirements for immunogenicity
- foreignness
- high molecular weight
- chemical complexity
- degradability
- genotype of host
- antigen dosage
- route of ag administration
- adjuvants
what classes of ag are not very immunogenic
carbs
lipids
nucleic acids
but virtually all proteins are imunogenic- each of the 4 levels of proteins structure contributes to immunogenicity
immunogen vs antigen
antigen binds to part of immune syst
immunogen causes immune response
all immunogens are antigens
if there were no GC, what process wont occur
SHM
CSR can occur outside of GC
can CSR be reversed
no