4-Viral Immunology and Vaccines

Question 1

On initial exposure … defenses are first and not specific to the pathogen.

Answer 1

innate

Question 2

Upon secondary exposure the … from the adaptive response can act fast to prevent disease.

Answer 2

antibodies and CTL’s

Question 3

What can also act on viruses to prevent infection on cells?

Answer 3

Antimicrobial compounds

Question 4

What is the first signal that an infection is taking place?

Answer 4

Type 1 Interferon (INF)

Question 5

Interferon is most well known for activating a large number of proteins that have …

Answer 5

antiviral properties

Question 6

What protein, activated by interferon, can shut down protein synthesis in an infected cell?

Answer 6

(PKR) Protein Kinase RNA

Question 7

What protein, activated by interferon, can activate RNase H that will degrade mRNA in an infected cell?

Answer 7

(OAS) oligo A synthetase

Question 8

What cells can kill infected cells helping stop the spread of the virus?

Answer 8

NK cells

Question 9

NK cells are most known for their ability to recognize cells that have …, to escape CTL killing.

Answer 9

downregulated their MHC I

MHC is a signal that a cell is healthy and normal

Question 10

What cells can sense a viral infection without being actively infected; and can make large amounts of Type I IFN in a viral infection - can’t shut down IFN production in these cells?

Answer 10

plasmacytoid DC

Question 11

What is an important part of the adaptive immune response to viral infections and will bind to the surface of a virus preventing the virus from infecting a cell?

Answer 11

Neutralizing antibodies

Question 12

What do viral antigens encountered in the mucosa (gut, upper and lower respiratory tract) primarily produce?

Answer 12

dimeric IgA

Question 13

What do viruses that have a viremic stage (viruses in blood) primarily produce?

Answer 13

IgG

Question 14

What is activated in the adaptive response to a viral infection because it kills infected cells, and also keeps chronic viral infections in check?

Answer 14

(CTLs) cytotoxic T lymphocytes

Question 15

What is a way that viruses subvert the immune system - via changing?

Answer 15

Virus changes its surface proteins and escape neutralizing antibodies by antigenic drift

Question 16

What is a way that viruses subvert the immune system - via immune suppression? (4)

Answer 16

• Blocking the Type I IFN response
• Downregulating MHC I
• Destroying CD4 cells
• Making decoy cytokine receptors

Question 17

When you encounter an antigen again what is responsible for binding to the virus, preventing infection and inducing sterilizing immunity?

Answer 17

the neutralizing antibodies present (IgA and IgG)

Question 18

The new strain is recognized well by antibodies from a previous strain, no new sickness?

Answer 18

Cross protection

Question 19

Antibodies bind with lower affinity. Can’t clear infection but get less sick. CTL’s might also help.

Answer 19

Partial cross-protection

Question 20

It is like a new infection to your body.

Answer 20

No cross protection

Question 21

What do you need to get a good vaccine?

Answer 21

Include viral proteins that might induce neutralizing antibodies to respond to the virus.

Question 22

What virus is best to use in a vaccine?

Answer 22

attenuated virus

Question 23

Whole killed virus vaccines have viral specific signals that will activate … on immune cells.

Answer 23

PRR - pattern recognition receptors

Question 24

Vaccines may include an adjuvant, a substance that …

Answer 24

activates the immune system

Question 25

What infections have attenuated virus vaccines, where the virus replicates just a little and the immune system sees it as normal and mounts an immune response? (9)

Answer 25

1. Measles, Mumps, Rubella
2. Varicella Zoster (chicken pox)
3. Shingles
4. Rotavirus
5. Nasal Influenza
6. Yellow Fever
7. Small Pox (not for general public)
8. Oral Polio (not in US)
9. Adeno type 4 and 7 (military only)

Question 26

What infections have whole killed virus vaccines, where the virus does not replicate at all, and much more killed virus is generally need in a vaccine? (4)

Answer 26

1. Inactivated Polio (not in US)
2. Hepatitis A
3. Japanese Encephalitis (travelers)
4. Rabies

Question 27

In what type of vaccine do you just have part of a virus so there is no chance of infection, have to make sure you use the correct protein to get a good neutralizing antibody response?

Answer 27

Subunit Vaccine

Question 28

What infections have subunit vaccines? (3)

Answer 28

1. Inactivated Influenza
2. Hepatitis B
3. HPV

Question 29

What passive immunization is natural in babies, transferred to the baby in the third trimester?

Answer 29

IgG

Question 30

What passive immunization with antibodies is natural in babies and is in colostrum and breast milk?

Answer 30

IgA

Question 31

Immunoglobulin is from normal blood donors and is given post exposure to help prevent infection of what? (2)

Answer 31

Hepatitis A, and Measles

Question 32

Hyperimmune IG is from people with a high titer to specific infection and is given post exposure to help prevent infection of what? (5)

Answer 32

Hepatits B, Rabies, Chicken Pox, CMV, Vaccinia

Question 33

Monoclonal antibodies to specific viruses are given post exposure to help prevent infection of what? (2)

Answer 33

RSV, and Ebola

Question 34

What is treated with post exposure vaccination? (4)

Answer 34

Rabies, HAV, HBV, Small Pox

Question 35

What is preventing the spread of an infection in a community to the unvaccinated by reducing the chance that the unvaccinated will come into contact with an infected person?

Answer 35

Herd Immunity

Question 36

What percentage of people need to be vaccinated to provide protection to the community?

Answer 36

75-95%