L18_B Cell Development and Immunity Flashcards Preview

Microbiology > L18_B Cell Development and Immunity > Flashcards

Flashcards in L18_B Cell Development and Immunity Deck (10):

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?