Term
|
Definition
-Ig-gene rearrangements occur during B cell development
-Heavy chains and light cahin are expressed separately (come together to form membrane bound Ig(BCR))
-generates the large repertoire of antibody diversity (10^11 different antibodies) |
|
|
Term
|
Definition
-VDJ gene segments
-random combination of gene segments produces diversity in the Ag binding sites of Igs
-constant region gene segments |
|
|
Term
| composing the Ig heavy chain |
|
Definition
-VDJC gene segment joining
-transcription of DNA
-splicing of RNA
-translation of mRNA |
|
|
Term
| how to chose gene segments |
|
Definition
-D and J segments join
-one variable heavy gene segements join D-J
-transcription of VDJ and constant gene segments
-splicing of VDJ to constant muRNA
-translation of heavy chain |
|
|
Term
|
Definition
-2 types (kappa and gamma)
-V and J gene segments
-random recombination of gene segments produces diversity in the Ag-binding sites of Igs
-constant region gene segements |
|
|
Term
| composing the Ig light chain |
|
Definition
-VJC segment joining
-transcription of DNA
-splicing of RNA
-translation of mRNA |
|
|
Term
|
Definition
-multiple gene segments
-combinatorial V-(D)-J joining
-juctional diversity (random +/- of nucleotide sequences at the juncitons between V, (D), and J gene segments (via exonucleases and transferases)
-combinatorial association of chains
-somatic hypermutation (high frequency point mutations, unique to germinal center (lymph node and spleen)) B cells) |
|
|
Term
|
Definition
-generation of b cell receptor repertoire in the bone marrow
-negative selection of b cell receptors that recognize 'self' components
-positive selection of b cell receptor to become mature and populate secondary lymphoid organs
-recirculation of mature b cells between lymph. blood, and secondary lymphoid organs;searching for infection
-b cell clone is activated and clonally expands in secondary lymphoid tissue
-generation and secretion of antibodies to attach infection;generation of memory b cells |
|
|
Term
| stages in b cell development |
|
Definition
-common lympoid progenitor cell
-pro-B cell
-pre-B cell
-immature naive B cell
-mature B cell
-stages are defined by the rearrangement and expression of immunoglobulin genes |
|
|
Term
|
Definition
-expression of a productive heavy chain Igmu gene segment(VDJ-C gene segment rearrangement, express heavy chain in association with surrogate light chain-identical in all pre b cells)
-expression of signaling molecules (provides signals for survival like BTK-Bruton's Tyr-K)
-rearrangement of light chain begins |
|
|
Term
|
Definition
-once a productive gene rearrangement is made, further rearrangement is terminated (non productive rearrangements get a second chance)
-ensures that each B cell produces Ig of a single specificity |
|
|
Term
|
Definition
-expression of productive heavy (VDJ-Cmu) and light chain (VJ-C)
-do not proliferate/differentiate in response to Ag |
|
|
Term
| one last test before they leave |
|
Definition
| -to prevent the emrgence of auto-reactive b cells, immature b cells are subject to selection |
|
|
Term
|
Definition
-central tolerance
-high avidity interaction with self-Ags
-rescued by receptor editing (change in receptor specificity)
-positive selection (express a complete antigen receptor(BCR), weak binding to self Ags influences BCR derived survival signals) |
|
|
Term
|
Definition
-responsive to Ag
-express IgM and IgD (naive b cell receptors)
-leave bone marrow (lymph node and spleen) |
|
|
Term
|
Definition
-selects for functional heavy chains
-selects for functional light chain;retain autoreactive clones |
|
|
