Lecture 6 - B cell activation Flashcards
how many signals are there for B cell activation?
2
signal 1 increases if there is lots of what present? (hint: complement)
C3b
BCR associated peptides have …… motifs?
ITAMS
the crosslinking of which receptors activates kinases?
BCRs
which 3 molecules form the BCR co-complex?
CR2, CD19, CD81
thymus independent antigens produce which Ig only?
IgM
thymus independent antigens deliver signal 2 to B cells in one of 2 ways.
what are these 2 ways?
signal delivered from antigen itself
signal delivered from BCR cross linking
do thymus dependent or thymus independent antigens give a better antibody response?
thymus dependent
with thymus dependent antigens, what cell type is required for signal 2 to reach B cells?
CD4+ T cells
thymus dependent antigens involve the …… ………. of antibodies?
class switching
in B cell activation with thymus dependent antigens, B cells initially divide to become what?
centroblasts
centroblasts (divided B cells) undergo what, leading to class switching of antibody isotypes?
somatic hypermutation
somatic hypermutation involves which enzyme?
AID
if a BCR does not bind to an antigen, and it has not become a non dividing centrocyte, what happens to it?
dies in lymphoid tissue
in germinal centres, B cells have which 3 options?
differentiate into plasma cells
differentiate into memory cells
die
