B-cell lymph Flashcards
What does each lymphocyte express
single antigen receptor specificity
What do naive lymphocytes produce to help respond to many numbers of antigens
identical clones
What are three stages of B-cell development
Maturation (Ag independent) (primary lymph)
Activation (Ag dependent) (second lymph)
Differentiation (Ag Dependent) (second lymph/tissues)
What is necissary for maturation of B-cell
IL-7 contact with stromal cells
What is one key component of lag phase
Colonial selection
What is allelic exclusion
Blocked VDJ arrangement of other heavy chain allele
What are some mechanisms of generation of specificity diversity
Genetic diversity Combinatorial VDJ joining Sloppiness P and N- region nucleotide addition Somatic hypermutation
What is combinatorial diversity
The combination of one V region with different D and J regions, and the combination of different heavy chains with light
Where does generation of specificity diversity occur
primary lymphoid organs
What is somatic hypermutation and where does it occur, key characteristics
Occurs in germinal center while B-cell divides in response to antigen.
Cells are rapidly dividing increasing chances of mutation, if mutation is bad the cell will die. Affinity will increase and colonal expansion will occur.
Fine tuning of antigen binding site of b-cells
Doesn’t change what B-cell recognizes
VDJ makes up what region of antibody
Variable region
What region is DNA mutated at a high rate at during somatic hypermutation
Complementary determining regions
How do you determine combinatorial association and where does it happen
(VxDxJ heavy chain) x (VxJ light chain) happens in primary lymp tissues
Where does somatic hypermutation occur
Second lymph tissue after it’s seen antigens
How does the B cell choose membrane bound vs secreted
Differential splicing
