Immunological Memory & Vaccination

Question 1

The primary immune response results in _____ (2).

Answer 1

1. Development of effector cells
2. Immunological memory

Question 2

True or false. You can only make pathogen-specific memory B cells

Answer 2

False. You can make all these

Question 3

True or false. Both effector and memory cells are made during the primary immune response.

Answer 3

True

Question 4

What is the function of FcγRIIB1 on the surface of naive B cells?

Answer 4

• Crosslinks IgG already produced for that specific antigen and signals that naive B cell to die
• Occurs when you already have a memory cell for that pathogen
• Prevents new IgM from being produced

Question 5

Why do memory cells respond more forcefully than their naive counterparts during a SECOND infection? (3)

Answer 5

1. Pathogen-specific memory cells outnumber naive cells
2. Memory cells are more readily activated
3. Memory B cells have already undergone isotype switching, somatic hypermutation, and affinity maturation (why waste energy?)

Question 6

True or false. Memory lymphocytes are more resistant to apoptosis than their naive counterparts.

Answer 6

True

Question 7

Why do memory T cells have an increased speed of response compared to naive T cells?

Answer 7

• Memory T-cells are already circulating
• Do not require authentication step
• Do not require co-stimulation via CD28

Question 8

Secondary immune responses are only made if ______

Answer 8

innate immunity and steady-state pathogenic antigen are not sufficient to clear a pathogen

Question 9

How are memory B-cells activated?

Answer 9

Pathogenic-specific CD4 T_FH cells

Question 10

CD45 is a tyrosine kinase on the surface of lymphocytes that is involved in TCR and BCR signaling. It is alternatively spliced into CD45RO on _____ cells and CD45RA on _____ cells.

Answer 10

• Effector and memory
• Naive

Question 11

Which form of CD45 has more robust signaling with the TCR/BCR?

Answer 11

CD45RO

Question 12

What is the function of L-selectin (CD62L) and CCR7 on central memory T cells (T_CM)?

Answer 12

Allows them to enter secondary lymphoid organs to be activated by APCs

Question 13

Why are CCD7 and L-selectin not expressed on effector memory T cells (T_EM)?

Answer 13

They are already mature and circulating in non-lymphoid tissue

Question 14

Where are central memory T-cells, effector memory T-cells, and resident memory T-cells located?

Answer 14

• TCM - circulated between blood, lymph, and secondary lymphoid tissue
• TEM - circulated from blood to non-lymphoid tissue
• TRM - based in non-lymphatic tissue; respond to local infections

Question 15

Newborn hemolytic anemia occurs when the father is Rhesus D (RhD) ______ and the mother is _____

Answer 15

• Father +
• Mother -

Question 16

Why does newborn hemolytic anemia only occur during a second pregnancy?

Answer 16

• The mother is not exposed to the baby’s blood until birth
• Memory cells created prior to second pregnancy

Question 17

Why do RNA viruses mutate more readily than DNA viruses?

Answer 17

RNA polymerase does not have the proof-reading and repair mechanisms that DNA polymerase has

Question 18

Which type of vaccine consists of virus particles that are treated chemically (formalin) or physically (heat/radiation)?

Answer 18

Killed or inactivated virus vaccines

Ex: Rabies and influenza

Question 19

What type of vaccine contains a mutant viral form of a virus that grows poorly in human cells and is no longer pathogenic?

Answer 19

Live-attenuated virus vaccines

Ex: Measles and mumps

Question 20

What are the pros vs. cons of oral vaccines?

Answer 20

• Pro - good for viruses that infect mucosal tissue
• Con - has to suffer the gut

Question 21

Which type of vaccine contains only one component of a virus?

Answer 21

Subunit vaccine

Ex: Hepatitis B vaccine - first subunit vaccine using recombinant DNA

Question 22

Toxoid vaccines are useful against ______

Answer 22

• Bacterial toxins
• High-affinity neutralizing antibodies prevent disease
• Ex: diphtheria & tetanus

Question 23

_______ vaccines contain different epitopes recognized by B- and T- cells that are synthetically linked together

Answer 23

Conjugate vaccines

Question 24

Polysaccharide vaccines produce high-affinity IG antibodies, but do not mount a CD4 T_FH cell response. Why?

Answer 24

MHCII molecules can only present peptides to naive CD4 T-cells

Question 25

What is the function of adjuvants?

Answer 25

Additive to a vaccine to assist in triggering the innate immune response

Question 26

_____ vaccines provide protection against more than one pathogen. Ex: DTP, MMR

Answer 26

Combination