Lecture 24 - Immune Memory

Question 1

Example of ancient documentation of immunological immunity

Answer 1

Thucydides documented immunological memory in his History of the Peloponnesian war
Treating plague

Question 2

What is immunity?

Answer 2

The ability to resist infection after previous exposure

Persists due to immune memory

Question 3

Classic epidemiological study demonstrating immune memory

Answer 3

Faroer Islands

Two measles epidemics. The survivors of the first didn’t get infected during the second

Question 4

When was smallpox officially eradicated?

Answer 4

1979

Question 5

Other successful vaccine campaigns
1)
2)
3)

Answer 5

1) Corynebacterium diphtheriae
2) Polio virus
3) Measles virus

Question 6

Difference in memory between humoral and cellular arms of the immune system

Answer 6

Humoral immunity remains constant (stable antibody titres over time)
Cellular immunity declines, with a half life of 10-15 years

Question 7

Cells which a germinal centre B cell can differentiate into
1)
2)

Answer 7

1) Bone marrow plasma cell

2) Memory B cell in lymph nodes or speen

Question 8

Which cell becomes the effector in short-lived extrafollcular antibody production?

Answer 8

Plasmablast

Question 9

Tfh and germinal centre B cell interactions required for immunological memory development
1)
2)
3)
4)

Answer 9

1) CD40/CD40L
2) ICOS/ICOSL
3) TCR/MHC
4) IL21/IL21R (IL21 R on B cell)

Question 10

Frequency of cognate B cells in a primary B cell response

Answer 10

1:10^4 - 1:10^5

Question 11

Frequency of cognate B cells in a secondary B cell response

Answer 11

1:10^2 - 1:10^3

Question 12

Main antibodies produced in a primary response

Answer 12

IgM, later IgG

Question 13

Main antibody isotypes produced in a secondary response

Answer 13

IgG, IgA

Question 14

Antibodies in breastmilk

Answer 14

IgA

Question 15

How long after birth until serum IgG levels reach those of an adult?

Answer 15

~10 years

Question 16

Immune response that most successful vaccines work through

Answer 16

Antibody response

Question 17

Examples of infections that aren’t immunised against using a vaccine that elicits an antibody response
1)
2)
3)

Answer 17

1) HIV
2) Mycobacterium tuberculosis
3) Influenza virus

Question 18

Location of naive T cells

Answer 18

Lymphoid

Question 19

Location of memory T cells

Answer 19

Lymphoid and tissues

Question 20

Role of maternal IgA

Answer 20

Protects the GIT of neonate

Question 21

Which cells can an activated T cell differentiate into?
1)
2)

Answer 21

1) Terminal effector cell (90% of T cells become these)

2) Memory cell

Question 22

Phenotype of terminal effector cells
1)
2)

Answer 22

1) IL-7R-

2) KLRG1+ (killer cell lectin-like receptor subfamily G1)

Question 23

Experiment demonstrating the importance of IL-7R and IL-15R
1)
2)
3)
4)

Answer 23

1) Mice infected with an antigen
2) Take IL-7+, IL-7- memory cells from mouse, place into new mice
3) Infect new mice with the same antigen
4) Mice that received IL-7R+ and expressed IL-15 generated stable memory. Mice that received IL-7R+ and didn’t express IL-15 had memory die off quickly.

Question 24

Cell surface receptor expressed by effector cells, not memory cells

Answer 24

IL-2R

Question 25

Helpless memory

Answer 25

Poor memory response when DC licensing is blocked (CD40/40L blocked)

Question 26

Subsets of memory T cells 1) 2)

Answer 26

1) Central memory T cells (in lymphoid organs) | 2) Effector memory T cells (extra-lymphoid tissues)

Question 27

Phenotype of skin-tropic circulating memory T cells 1) 2)

Answer 27

1) CLA+ | 2) CCR4+

Question 28

Phenotype of GIT-tropic circulating memory T cells 1) 2)

Answer 28

1) Alpha4:beta7 integrin | 2) CCR9+

Question 29

CLA

Answer 29

Cutaneous leukocyte antigen. | An E-selectin ligand expressed by skin-tropic T cells in humans

Question 30

Central memory T cell phenotype 1) 2)

Answer 30

1) CCR7+ | 2) CD62L+

Question 31

Effector memory T cell phenotype 1) 2) 3)

Answer 31

1) CCR7+/- 2) CD62L- 3) CCR5+

Question 32

Central memory T cell location 1) 2) 3)

Answer 32

1) Blood, lymphoid tissues 2) Lymph nodes 3) Spleen 4) Bone marrow

Question 33

``` Effector memory T cell location 1) 2) 3) 4) 5) ```

Answer 33

1) Blood, non-lymphoid tissue 2) Skin 3) Lungs 4) GIT 5) Liver

Question 34

``` Central memory T cell functional properties 1) 2) 3) 4) ```

Answer 34

1) Proliferative potential 2) IL-2 expression 3) Recirculation 4) Poor effector function

Question 35

``` Effector memory T cell functional properties 1) 2) 3) 4) ```

Answer 35

1) Poor proliferative potential 2) No IL2 expression 3) Recirculation 4) Effector function

Question 36

Acute infection memory T cell response

Answer 36

Mostly effector memory T cells

Question 37

Late memory T cell makeup

Answer 37

Almost all central memory T cells

Question 38

In the skin, where do memory CD8+ T cells cluster?

Answer 38

Epidermis

Question 39

In the skin, where do memory CD4+ T cells cluster?

Answer 39

Dermis, hair follicles

Question 40

Difference in migration patterns in tissue-resident memory T cells 1) 2)

Answer 40

1) CD8+ are fairly static | 2) CD4+ move around a lot

Question 41

CD8+ T cells found in the skin

Answer 41

Permanently tissue-resident CD8+ memory cells

Question 42

``` Permanently tissue-resident CD8+ memory cell phenotype 1) 2) 3) 4) ```

Answer 42

1) High CD103 2) High CD69 3) CD62L- 4) CCR7-

Question 43

CD103

Answer 43

Adhesion molecule

Question 44

CD69

Answer 44

Involved in migration

Question 45

Comparison between phenotypes of T effector memory and T tissue-resident memory

Answer 45

Similar, but T effector memory have CCR5, and T tissue-resident memory express CD103 and CD69

Question 46

``` Tissue-resident memory T cell location 1) 2) 3) 4) 5) 6) ```

Answer 46

1) Mainly non-lymphoid tissues 2) Skin 3) GIT 4) Lungs 5) Brain 6) Particularly common in areas after local inflammation

Question 47

``` Tissue-resident memory T cell functional properties 1) 2) 3) 4) ```

Answer 47

1) Probably don't have proliferative potential 2) No IL-2 3) No recirculation 4) Effector function

Question 48

Probable role of tissue-resident memory T cells 1) 2)

Answer 48

1) Sit in places (EG: epidermis) where circulating memory T cells don't go 2) Control persistently or recurrently occurring infections

Question 49

Example of infection controlled by tissue-resident CD8+ memory cells

Answer 49

Herpes simplex virus | Latent in dorsal root ganglia, constant viral reactivation, but controlled by tissue-resident T cells