Overview of the adaptive immune system

Question 1

definition of adaptive immune response

Answer 1

that part of the immune system that enhanced rapidity, potency or specificity as a consequence of previous events

Question 2

what are the 4 basic approach to spotting a pathogen

Answer 2

1) generic recognisable features (PAMPS)
2) presence associated with damage (DAMPS)
3) memory/ previous exposure
4) autoimmunity (identifying non self )

Question 3

B cell associated syndromes/defects (3pts)

Answer 3

• Congenital agammaglobulinaemia
• Common variable immunodeficiency (CVID)
• Novel biologics - Rituximab

Question 4

T cell associated syndromes/defects (3 pts)

Answer 4

• Severe Combined Immunodeficiency (SCID)
• DiGeorge syndrome -thymic failure
• Acquired — HIV / Chemotherapy / Novel biologics

Question 5

which 3 cells are known as lymphocyte

Answer 5

NK
T cell
B cell

Question 6

what are the difference between MHC I and MHC II

Answer 6

MHC 1:
recognised by CD8
intracellular 
MHC 2:
CD4
extracellular but phagocytosed

Question 7

TEM: Effector Memory cells

Answer 7

• short-lived population
• continually replenished
• doubling time about 15 days
• CCR7 - CD62L-
• migrate into tissue

Question 8

TCM: Central Memory cells

Answer 8

• turnover at a significant rate
• Doubling time about 48 days
• CCR7+ CD62L +
• enter LN and circulate

Question 9

Treg: Regulatory T-cells

Answer 9

• Also very dynamic

* Control the responses of other T cells

Question 10

Basic tenet of one cell/one specificity for B cells

Answer 10

For B cells — one cell, one Ig

• Defined by their antibody
• May class switch / undergo affinity maturation
• but always the same basic Ig

Question 11

Basic tenet of one cell/one specificity for T cells

Answer 11

For T cells — one cell, one T cell receptor — TCR

• Selection and expansion of that clone ± differentiation
• Retention in “memory” of clonal progeny

Question 12

what is usually present in the MHC groove

Answer 12

A peptide

Question 13

Central Memory t cell

Answer 13

CCR7+ and CD62L+

Enter LN and recirculate

Question 14

Effector Memory t cell

Answer 14

CCR7- CD62L- 
Migrate into tissues 
Rapid effector activity 
— Cytolytic, Cytokines 
(IFg/rL4/1L-5)

Question 15

turnover of TEM and CEM

Answer 15

Effector Memory CD4 T cells have faster turnover

than Central Memory T cells

Question 16

B cell repertoire selection

Answer 16

Positive selection 
Receptor editing 
Negative selection 
Transition to IgM+ IgD+ mature B cell 
Antigen recognition leads to proliferation/differentiation 
Activated B cells transform into Plasma cells 
"Antibody factories" 
- also produce CD27+ memory B cells