B Cell Immunity Flashcards
What are the 3 kinds of B cells?
B-1 Cells
Conventional B-2 Cells
Marginal Zone B Cells
Where does antigen independent development occur?
Bone Marrow
Where does antigen dependent development occur?
Outside of the bone marrow
Where and when are B-1 cells made?
B-1 cells - made in the fetal liver and only made at that time and they self-renew
Where are marginal zone B cells made?
Spleen
What do B-1 and marginal zone B cells generally respond to?
Carbohydrate antigens
What B cells do not need T cell help?
MZ B cells and B-1 don’t need T cell help and don’t have memory which is why they are referred to as innate-like cells
How does dose affect the immunogen response?
Need minimum dose to trigger antibody formation
What size antigens are the most immunogenic?
Larger antigens
What is an example of a small antigen that is not strongly immunogenic?
Insulin
What are the 2 signals required for B cell activation?
- Presentation of antigen via MHC Class II
2. Signal from a T cell (CD40-CD40L)
How does affinity maturation occurs?
Somatic hypermutation to increase the affinity of B cells
What are the events occurring in the germinal center?
- Somatic hypermutation
- Class switch recombination
- Development of memory B cells and plasma cells
How are high affinity B cells selected for?
By the T cells
What is the function of follicular dendritic cells?
Antigen lies on the follicular dendritic cell surface so B cells can see the antigen and take it up and present that to a T cell.
FDC are not APCs
