Immunological Memory

Question 1

2 major goals of adaptive immune response

Answer 1

Control infection, remember pathogen

Question 2

Immunologic memory

Answer 2

Property of remembering specific adaptive immune responses

Question 3

2 factors contribute to defence by immunological memory

Answer 3

Circulating antibodies at low concentrations, ability to mount accelerated secondary response from memory cells.

Question 4

Seasonal immunity

Answer 4

Antibodies produced during primary response prevent reinfection for months

Question 5

Major differences between primary and secondary responses

Answer 5

Strength (affinity maturated) and speed (clone and proliferation of memory cells)

Question 6

Components of imm. memory

Answer 6

Circulating Abs, T and B-memory cells.

Question 7

Memory B cells are derived from which cells?

Answer 7

High affinity cells emerging from germinal center.

Question 8

Short/long-lived plasma cells

Answer 8

Short are derived from low-affinity B-cell shortly after infections, long-lived are class-switched and high-affinity.

Question 9

CD27

Answer 9

Expressed by memory B-cells

Question 10

Long-lived plasma cell

Answer 10

Large, no surface Ig, isotype-switched.

Question 11

Short-lived plasma cell

Answer 11

Large, no surface Ig, not class-switched.

Question 12

Which cells are mainly responsible for high concentrations of antibody after primary response?

Answer 12

Short-lived plasma cells.

Question 13

Ab life time

Answer 13

Last ca. 6 months.

Question 14

Residual Ab levels

Answer 14

Are maintained by memory B-cells and long-lived plasma cells.

Question 15

Homeostatic proliferation

Answer 15

Prol. in absence of external stimulation. Can be followed by diff. into long-lived plasma cells.

Question 16

Reasons for faster and stronger secondary response

Answer 16

Higher precursoer frequency, optimal BCRs, more reactive.

Question 17

FcγRIIB1

Answer 17

Inhibitory receptor expressed in naive B cells. Prevents activation of already known antigens by binding to Ab already bound on antigen.

Question 18

With age the pool of memory B cells…

Answer 18

Becomes larger while the naive B cell pool becomes smaller.

Question 19

Solution to HAN

Answer 19

Infusing mom with anti-Rh antibody.

Question 20

Major feature of secondary B cell response

Answer 20

Inhibition of activation of naive B cells

Question 21

How to discern between naive, effector and memory T cells

Answer 21

Protein expression

Question 22

Memory T cell life time

Answer 22

Often entire lifespan

Question 23

Maintenance of memory T cells

Answer 23

Homeostatic proliferation.

Question 24

Reasons for stronger secondary T cell response

Answer 24

Outnumbers naive T-cells, more readily activated - less dependent on co-stimulation and more sensitive to cytokines.

Question 25

Tcm

Answer 25

Central memory. Slower activation, may produce more effector cells.

Question 26

Tem

Answer 26

Effector memory. Respond immediatly at sites of infection.