Immunology 1: Vaccination

Question 1

What is a vaccination?

Answer 1

Developing immunity against a particular pathogen, either naturally or via vaccine.

Question 2

What is immunological memory?

Answer 2

The ability of the immune system to recognise a previous pathogen that affected the body and produce a more efficient response.

Question 3

Which 4 cell types of the immune system show immunological memory?

Answer 3

1. Memory CD4+ T cells 2. Memory Cytotoxic T cells 3. Memory B cells 4. Long lived plasma cells

Question 4

Which two Ig types are primarily involved in the immune response?

Answer 4

1. IgG 2. IgM

Question 5

What is the difference in the pattern of Ig production in primary vs secondary response?

Answer 5

Primary- IgM first, takes two weeks for IgG to be produced and be the most prominent IG.

Secondary- IgG and IgM both produced at the start, IgG at the higher concentrations

Question 6

How is the memory based immune response different to primary infection?

Answer 6

Response generated is much quicker, and a lot stronger (greater number of specific effector cells produced)

Question 7

Vaccination can also generate memory T & B cells. T/F?

Answer 7

True

Question 8

Second and subsequent exposure to a pathogen is more rapid and aggressive. T/F?

Answer 8

True

Question 9

What five factors makes the secondary immune response faster?

Answer 9

1. Memory cells present in greater numbers
2. Memory CD8+ cells can immediately kill pathogens
3. Memory CD4+ cells can immediately produce cytokines
4. Memory B cells have already undergone hypermutation and can immediately produce high conc of IgG and other high affinity antibodies
5. Memory cells have enhanced properties of cell adhesion and chemotaxis.

Question 10

What is the difference between active and passive immunity?

Answer 10

1. Active- Immunity generated by the person themselves. Can be via vaccine or natural 2. Passive- Immunity gained from other person/animal

Question 11

Active immunity tends to be permanent while passive usually temporary. T/F?

Answer 11

True

Question 12

What are the 4 different ways of inducing immunological memory?

Answer 12

Exposure to

1. Infectious organism
2. A similar but less virulent pathogen
3. An inactivated form of the pathogen
4. A less virulent but the same pathogen.

Question 13

What is variolation?

Answer 13

Exposure of people to small pox derived from other individuals

Question 14

Exposing someone to coxpox to prevent immunity from small pox is an example of?

Answer 14

Active immunity- exposure to similar but less virulent pathogen

Question 15

Exposing someone to an inactivated form of the pathogen is more effective than using an active form. T/F?

Answer 15

False. The response is mediated primarily by antibodies, not T cells Needs multiple doses to stimulate effect

Question 16

What are the two main symptoms of polio?

Answer 16

1. Muscle weakness 2. Paralysis

Question 17

People who have polio are usually asymptomatic. T/F?

Answer 17

True

Question 18

What are the pros of inactivated vaccines? (2)

Answer 18

• Can be made quickly - Can be given to immunocompromised

Question 19

Disadvantages of inactivated vaccines? (3)

Answer 19

• May be difficult to stimulate immune response to killed organism
• No T cell production
• Requires repetitive exposure to generate response

Question 20

What are adjuvants?

Answer 20

Inflammatory substances administered with the vaccine to boost the chances of an immune response

Question 21

Pros and cons of adjuvants? (1 each)

Answer 21

Pro -inflammatory substances stimulate antibody & T cell production

Cons- Response may be generated to vaccine:protein conjugate rather than to the vaccine itself

Question 22

Difference between whole cell and subunit vaccines?

Answer 22

Whole cell- all of pathogenic organism used (Hep A) Subunit- only part of the organism used (Hep B) Polysaccharide vaccines- sugars from outer capsule of bacteria used to generate immunity to the bacteria

Question 23

What is a live attenuated virus?

Answer 23

Using a weakened form of the pathogen (Eg measles, mumps, BCG)

Question 24

Main advantage and disadvantage of attenuated virus?

Answer 24

Adv- V similar to natural infection, so produces near similar immune response (similar T & antibodies) Disadv- Can cause infection in immunocompromised host

Question 25

What is a natural form of passive immunity?

Answer 25

Maternal antibody transfer to growing foetus. Provides immunity at the time and imp for memory of immunity too. Can be through breast milk or trans-placental transfer of IgG

Question 26

What is the other form of passive immunity ?

Answer 26

Therapeutic passive immunisation- Taken from unrelated individuals - pooled normal human immunoglobin - hyper immunoglobin Pooled - Taken from a bank of people who have immunity to the virus Hyper- taken from peeps with high antibody levels against the pathogen