Know the different cells that can become plasma cells - correct answer ✔✔Activated B cells
Isotope switched, somatically hyper mutated centrocytes
Memory B cells
What are the components of the B cell co receptor? (CR2 is one of them) - correct answer ✔✔CR2 -
binds to complement deposited on pathogen
CD19 - receptor signaling
CD81 - binds to CD19 and is essential in bringing it to the B-cell surface
What does CR1 do for the co receptor? - correct answer ✔✔CR1 on B cell binds to C3b on the pathogen
that makes it susceptible to cleavage to C3D. CR2 part of the B-cell co receptor can then bind to the C3D
where signal is sent through CD19.
What does TI antigen mean? What makes these different than TD antigens? - correct answer ✔✔TI
means Thymus Independent. This means that B-cells can activate without T-cell help like infants with
DiGeorges syndrome. TI B cells activates through cross linking.
Describe B cell activation, CD40 ligand, CD40, NFkB, ICAM-1, and IL-4 secretion by T cells. - correct
answer ✔✔
Follicular Dendritic Cells - correct answer ✔✔1. Follicular dendritic cells hold onto immune-complexes
2. FDC's have CR1 and CR2
3. FDC's lack phagocytic abilities and have extensive s.a
What is in each other FDC zones? (Dark zone/light zone) - correct answer ✔✔Dark zone
1. Centroblasts - rapidly dividing activated B-cells
2. Going through somatic hypermutation and isotope switching/ no BCR on surface.
, Light Zone
1. Centrocytes
2. Slowling non diving B cells with mutated isotype switched BCR.
3. Express BCR again to test against Ag.
What happens to the cells in the FDC zones? - correct answer ✔✔The FDC Zones are located in the
Germinal Center
In the Dark zones
1. FDC's secrete - IL-6, IL-15, 8D6, and BAFF for the proliferation of centroblasts and Tcells.
2. Where Tfh attach to B-cells with their CD40 ligands it induces AID which provides somatic
hypermutation and isotope switching of the B cell.
In the Light Zones?
1. Slowly non-dividing centrocyte that will interact with Ag's held by FDC's.
How to antibodies function? Do they destroy the pathogen directly or do they tag and cover up things? -
correct answer ✔✔Antibodies recruit "destructive, nonspecific" immune system components to the
infecting pathogen. Ab's bind and link the pathogen to effector molecules or cells that will destroy the
pathogen.
They neutralize and activate complement.
Opsonize
bind to mast cells and basophils.
What is the B cells role in its activation? What are the steps of activation in the LN? - correct answer
✔✔To become a plasma cell.
Hyper-IgM Syndrome - correct answer ✔✔People who lack CD40 ligand..
1. Mostly in Males
2. Almost no IgG or IgA
3. B cells unable to Isotope switch.