L18_B Cell Development and Immunity Flashcards
What is the main location of B-cell development in the fetus? in the Adult?
Fetus- Liver
Adult- Bone marrow
What type of “screening” of B-cells happens in the bone marrow, what is receptor editing?
B-cells that are self reactive in the bone marrow will be retained. If a B-cell is self reactive in the bone marrow it can undergo receptor editing in which it can continue to rearrange its light chains in attempt to product a Ab that is not self reactive. If It is successful it will leave the bone marrow, if not it will apoptose
What happens if a B-cell does not target a lymph node within 3 days of exiting the bone marrow?
It dies
What happens if a B-cell sees antigen and is not stimulated by a T-cell?
It becomes anergic and dies
Give a brief description of how Type 1 and Type 2 T-independent antigens work and give an example of each.
T-independent antigens are in most cases bacteria products (not necessarily proteins, thus T-cells can react) Type 1 receives signal though antibody binding as well as additional signals through TLRs an example is responses mediated by LPS or Gram Neg Bacteria. Type 2 are generally stimulated by repeated antigen sequences that crosslink antibodies. An example of type 2 is the polysaccharide coat of pneumococcus.
What is the cluster of few T-cells helping many B-cells initiate an antibody response called?
Germinal Center
What is unique about follicular dendritic cells?
They are not actually dendritic cells, but they can hold native antigen out for B-cells to interact with in the germinal center
Where does all class switching and affinity maturation occur?
The germinal center
What cytokine triggers a B-cell to become a Plasma Cell? What cytokines trigger a B-cell to become a memory cell?
Plasma cell- IL10
Memory - IL4
Does a plasma cell have surface IgG and MHC II?
NO
