Fichas
8 - B cell development part 1
Fichas del conjunto (57)
- 1how can we identify and target B cells therapeuticallybased on their surface expressed molecules
- 2give some examples of surface molecules expressed by B cellsBCR
CD20 - cancer immunotherapy target
molecules that communicate with CD4 T cells - 3what complement pathway are antibodies involved inclassical opsonisation (labelling pathogen with antibodies labels them as bad)
- 4where are B cells made in a foetus versus a born personfoetal liver
bone marrow - 5how many B cell populations are there3 - shows complexity
- 6where do antibodies come fromthe B cell receptor
- 7what do B cells need to do to start producing antibodiesdevelop into a plasma cell
- 8give an overview of a B cell lifecyclestem cell differentiation in bone marrow
random BCR generation (diversity)
B cells migrate to lymph node to encounter antigen + T cells
develop into plasma cell and produce antibodies if encounter antigen - 9what is the first stage in B cell property aquisitionheavy chain expression
- 10describe the steps of heavy chain developmentearly pro-B cell
late pro-B cell
large pre-B cell - 11explain early pro-B cell stagediversity and joining genes rearrange
- 12explain late pro-B cellvariable gene rearranges with the DJ region
- 13explain large pre-B cellsurrogate light chain added to test functionality of heavy chain
- 14what happens once functionality of heavy B cell chain is confirmedlight chain can start forming
- 15what occurs in formation of light chainVDJ genes all rearrange
light chain is paired with heavy chain intracellularly and complex moves to surface - 16what is the first immature B cell receptor formed asIgM (Mu)
- 17what does further maturation of the B cell causeproduction of both IgM and IgD on surface of B cell
- 18what is meant by a non productive link/join and how many are non productivemany of the joinings of the different v, d, j regions in both heavy and light chains fail (70%)
- 19what happens if productive link V-DJ rearrangement fails on first chromosome of heavy chainattempt V-DJ rearrangement on second chromosome
- 20what happens if productive link V-DJ rearrangement fails on secondchromosome of heavy chaincell is lost
- 21what are the two types of light chainkappa and lambda
- 22which light chain is produced firstkappa
- 23which light chain is produced if the firsts 2 chromosome rearrangements are non productive linkslambda
- 24what do productive and non productive links in B cell (receptor) develop allow forcontrolled process - ensures specificity
- 25why/how is further recombination of the genes preventedRAG expression
- 26what is allelic exclusionRAG preventing further recombination once a successful BC has been produced
- 27what does allelic exclusion ensureB cell produces antibodies of one specificity
- 28where do B cells develop specifically in the bone marrowon stromal cells
moving further into the bone marrow as they mature - 29as they develop what changes about the B cell that allows us to identify and mark them and the developmental stage they are atdifferent surface expressed molecules
- 30what do the stromal cells give the B cellsscaffolding
contact dependent support
cytokine support - 31how do you prevent autoimmunityremoving B cells that recognise self
- 32B cells are very similar appart fromvery unique BCR that recognises unique target
- 33what happens if a B cell recognises multivalent self moleculeclonal deletion
repetoire editing
apoptosis - 34what is clonal deletionthe removal of B cell through apoptosis that has a BCR that recognises self antigens
- 35what is repetoire editingB cells that recognise self antigen with mature receptor undergoes more gene rearrangement
- 36what occurs if B cell recognises soluble self molecules/antigensmigrates to periphery and switches off
not dead but unresponsive to any antigens (self or normal) - 37what is this process of testing against self antigens called and where does it occurnegative selection
bone marrow - 38what occurs if the B cell does not recognise multivalent or soluble self antigensmigrates to periphery and becomes a mature B cell
- 39what is positive selectionthe B cells being able to enter the lymph node and detect antigens
- 40what factors determine positive selection of B cellits half life (3-8 weeks)
if it is lower than this then it isn't moved into the lymph - 41describe the B cell form when it is positively selected and enteres the lymphnaive long lived
- 42once the B cell has entered the lymph and encounters an antigen describe its formmature recirulating
memory B cells
high affinity IgG, IgE, IgA expressed - 43summary: pro-B cells undergoHC gene rearrangement
- 44summary: pre-B cells undergoLC gene rearrangement
- 45summary: immature B cells expresssurface IgM
exit the BM
negative selection if recognise self or bind too strongly to antigen - 46summary: mature B cells expressIgM and IgD
circulate and enter immune response (lymph) - 47what part of antibody influences its functionIg heavy chain
- 48what is the first antibody releasedIgM
- 49what is the most abundant antibody and how many forms are there?IgG 1-4
- 50what is the least abundant antibodyIgE
- 51do memory B cells secrete antibodyno but if the antigen is re-encountered
- 52what are properties of a resting B cell that then get switched off when it becomes a plasma cellMHC presentation
surface Ig's
isotype switching
somatic hypermutation
growth - 53what are the intrinsic resting b cell propertieshigh surface Ig
MHC class II presentation to T cells - 54what are the inducible properties of a resting B cellsomatic hypermutation
isotype switching
growth - 55what are the two types of antibody response development pathwayT-independent (extrafollicular) e.g. in spleen
T-dependent (follicular) e.g. T zones, follicles in germinal centres - 56describe the types of antibody in T-independent and T-dependent antibody response developmentT-independent: IgM, some IgA, low affinity
T-dependent: IgM, IgG, IgA, IgE, high affinity, memory, long-lived - 57—
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- Descripción
- Year 2 (Immunity and infection ) Biomedicine Year 2 Fichas sobre 8 - B cell development part 1, creado por Georgie Philpott el 20/12/2022.
- Creado por
- Georgie Philpott
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