Memory and vaccination

Question 1

The adaptive immune system is mature at birth. True or false?

Answer 1

False - immature

Question 2

What are the three antigen presenting cells?

Answer 2

Dendritic cells
B cells
Macrophages

Question 3

Only antigen presenting cells can activate CD4 cells. True or false?

Answer 3

True

Question 4

Antigen presenting cells are the only ones that can present MHC Class II molecules. True or false?

Answer 4

True

Question 5

All nucleated cells in the body produce MHC Class I molecules. True or false?

Answer 5

True

Question 6

What are the four main functions of antibodies?

Answer 6

Opsonisation
Neutralisation
Complement activation
Antibody dependent cytotoxicity

Question 7

Antibodies cannot bind to toxins. True or false?

Answer 7

False - bind to toxins and neutralise them

Question 8

Cells infected with a virus or bacteria are eliminated by CD4 cells. True or false?

Answer 8

False - CD8 and Tc

Question 9

What are B cells?

Answer 9

Cells that can produce antibodies. They are antigen presenting cells

Question 10

Dendritic cells respond first to an infection that occurs in the periphery of the body. True or false?

Answer 10

True

Question 11

Where are dendritic cells found?

Answer 11

thymus, lymph nodes and spleen

Question 12

Humoral immunity is the principle defence mechanism against intracellular microbes and toxins. True or false?

Answer 12

False - extracellular microbes

Question 13

Cell-mediated immunity is the principle defence mechanism against extracellular microbes. True or false?

Answer 13

False - intracellular

Question 14

How are infected cells killed by Tc lymphocytes?

Answer 14

CTL precursors are activated
TCR-MHC mediated recognition of target cells and re-orientation of the killing machinery on target cell through polarisation
lytic granules contained in cytoskeleton and cytoplasmic vesicles are orientated towards area on target cell where MHC class I engages with TCR
lytic granules within T cell fuse with cell membrane releasing contents into small gap between T cell and target cell
cytotoxins are deposited on the surface of target cell and pores are formed by perforin which allow the entry of granzyme B - apoptosis
Tc cell not killed in process

Question 15

What is a vaccine?

Answer 15

a suspension of dead, attenuated or otherwise modified microorganism for inoculation to produce immunity to a disease

Question 16

All vaccines are prophylactic. True or false?

Answer 16

False - can also be therapeutic

Question 17

What is meant by vaccine immunogenicity?

Answer 17

The ability of vaccine to induce antibodies

Question 18

What is meant by vaccine efficacy?

Answer 18

reduction in incidence of disease among those who received vaccine compared to those who haven’tq

Question 19

What is meant by vaccine effectiveness?

Answer 19

ability of vaccine to protect the community and is revealed after vaccine is introduced in vaccination programme

Question 20

The whooping cough vaccine includes a killed virulent organism. True or false?

Answer 20

True

Question 21

What is an example of a vaccine that contains a live non-virulent strain?

Answer 21

Rubella vaccine

Question 22

The diptheria vaccine contains a modified toxin. How does this work?

Answer 22

Modified version of the toxin treated with heat or chemicals, shouldn’t produce symptoms but still triggers an immune response

Question 23

The hep B vaccine includes genetically engineered antigens. True or false?

Answer 23

True