Quiz 5 Part 1 Flashcards
B cells derive from what precursor
common lymphoid
The bone marrow generates around ______B cells per day
60 billion
The bone marrow generates around 60 billion B cells per day.
This this mean there are 60 billion B cells circulating in your blood/lymph
NO - these are kept as a reserve in case you get infected
B cells have how many distinct phases of development?
6
Do all B cells progress through all 6 stages of development?
NO. there are checkpoints where some B cells get “kicked out” before they go through all 6 stages
true or false:
only a fraction of B cells ever encounter an antigen
true
in B cell development:
phases 1-3 occur in __________
phases 4-6 occur in __________
phases 1-3 occur in PRIMARY lymphoid tissue (bone marrow and the thymus)
phases 4-6 occur in SECONDARY lymphoid tissue
state phases 1-3 of B cell development (occurs in primary lymphoid tissue)
- Assembly of a B cell receptor
- ELIMINATE B cells that bind “self” antigen
- B cell passes the test and is allowed to leave the bone marrow
“generation of diverse and clonally expressed B-cell receptors in the bone marrow.”
what phase of B cell development is this?
what is a “nickname” for this phase?
phase 1
“repertoire assembly”
“alteration, elimination, or inactivation of B cell receptors that bind to components of the human body”
what phase of B cell development is this?
what is a “nickname” for it?
phase 2
this is known as NEGATIVE SELECTION
“Promotion of a fraction of immature B cells to become mature B cells in the secondary lymphoid tissue”
What phase of B cell development is this?
what is a “nickname” for it?
3rd phase
POSITIVE SELECTION
If these B cell receptors DO recognize “self” and don’t get eliminated, what occurs?
an autoimmune disease
List phases 4-6 of B cell development (occurs in secondary lymphoid tissue)
- Factors in secondary lymphoid tissue attract circulating B cells
- B cell is activated by antigen in secondary lymphoid tissue
- Factors differentiate B cells into plasma cells
“recirculation of mature B cells between lymph, blood, and secondary lymphoid tissues”
what phase of B cell development is this?
what is an easier way to put it?
phase 4
searching for infection
“activation and clonal expansion of B cells by pathogen derived antigens in secondary lymphoid tissue”
what phase of B cell development is this?
what is an easier way to put it?
phase 5
finding infection
“differentiation to antibody-secreting plasma cells and memory B cells in secondary lymphoid tissue”
what phase of B cell development is this?
what does this mean in a nutshell
stage 6 (last stage)
attacking the infection
is the assembly of the B cell receptor dependent on genetics?
yes
Progression through phases of B cell development is accompanied by the expression of _________
surface makers