The development of B lymphocytes Flashcards
B cell lineage
pluripotent hematopoietic stem cell -> common lymphoid progenitor -> B-cell precursor -> pro-B cell
what stage does a immunoglobulin start being made in the bone marrow
during large pre-B cell a mew heavy chain is made
what stage in the bone marrow does the heavy chain genes start forming
early pro-B
during which stage in b-cell development is the light chain genes develop
in small pre-b cell
does the B cell need to remain in contact with the bone marrow while it develops
Yes
what % of late pro-b cells die by apoptosis during H chain gene rearrangement
50%
which receptor monitors the quality of immunoglobulin heavy chains
pre-B cell receptor
which receptor causes allelic exclusion at the immunoglobulin heavy chain locus
pre-B cells
what happens during allelic exclusion on the immunoglobulin heavy-chain locus
- RAG gene expression stops
- RAG proteins degraded
- other DNA locus is reorganized to prevent rearrangement
when does rearrangement of the light chain loci occur
in pre-B cells
do B cell tumours carry chromosomal translocations in order to join immunoglobulin genes with genes that regulate cell growth
yes
what cells scan in the bone marrow for self-reactive B cells
stromal cells and blood cells
what is the term for antigen receptors of autoreactive immature B cells that can be modified by a certain cell
receptor editing
what happens if editing does not occur in the immature B cells
clonal deletion
what is the term for a cell becoming unresponsive, so cells will still bind but will not activate any cascades
anergic
