Antibody, Lymphocytes and Generation of Diversity

Question 1

Features of adaptive immunity?

Answer 1

Not as fast as innate
more specific
has memory

Question 2

What is a T-cell receptor?

Answer 2

a heterodimer

binding site for antigen

Question 3

What is a B-cell receptor?

Answer 3

is an antibody
two identical heavy and light chains
two binding sites

Question 4

Variability of the immune response?

Answer 4

heavy chain is made of 3 parts, variable, diversity and joining
These parts can have over 2000000 different arrangements which allow for combinatorial diversity

Question 5

What is junctional diversity?

Answer 5

Chains dont have precise joining, nucleotides are added and removed from junctions during combinatorial arrangement which adds further diversity

Question 6

Differentiation of T-cells?

Answer 6

Cytotoxic t-cells - differentiate to secrete cytotoxic granules
Helper t-cells - differentiate to produce different sets of cytokines such as Th1, Th2, Th17 and Treg

Question 7

What happens to activated B-cells?

Answer 7

Turn into plasma cells

Question 8

What are the 5 types of antobodies?

Answer 8

IgM, igG,igA, igE and igD

Question 9

What are the functions of antibodies?

Answer 9

neutralise toxins and viruses
opsonise pathogens by promoting phagocytosis
activate complement cascade (C3)
agglutinates particles

Question 10

Function of igG?

Answer 10

main serum antibody

good at opsonisation

Question 11

Function of igA?

Answer 11

used for agglutination and neutralisation

Question 12

Function of igM?

Answer 12

aids agglutination

Question 13

Function of igE?

Answer 13

Mast cells have receptors for these

Question 14

What happens in germinal centres?

Answer 14

B-cells in the germinal centre starts to divide rapidly and they start to mutate their immunoglobulin variable region
high affinity variants are selected in the germinal centre
b-cells can also class switch in germinal centres

Question 15

Which cells leave the germinal centres?

Answer 15

Memory b-cells and plasma cells

Question 16

What is the primary response?

Answer 16

slower
low total antibody
igG lower in antibody concentration
igM higher in primary response
lag time

Question 17

What is the secondary response?

Answer 17

Faster
higher total antibody
igG higher
igM lower 
no lag time
longer lasting effect