Exam 3: Dr. Pharr Vaccination Strategies

Question 1

What is a vaccine?

Answer 1

A preparation of living or inactivated pathogens as an antigen

Question 2

What is a vaccination?

Answer 2

Administration of a living or inactivated pathogen to induce an immune response

Question 3

What are general concepts about vaccine-induced immunity?

Answer 3

Protective immunity

Immunological memory

Question 4

Describe protective immunity in vaccine-induced immunity

Answer 4

Vaccine-induced effectors prevent re-infection
Long-lived plasma cells in the bone marrow maintain antibody levels in the bloodstream to neutralize the pathogen at the site of pathogen invasion

Question 5

Describe immunological memory in vaccine-induced immunity

Answer 5

Vaccine-induced memory lymphocytes will not prevent re-infection, but can prevent disease or at least reduce severity of disease
Vaccine-induced memory lymphocytes circulate through secondary lymphoid tissues

Question 6

What are the characteristics of killed vaccines?

Answer 6

Killed vaccines generally result in an antibody response

Very poor inducer of cytotoxic T cells

Question 7

What happens when multiple doses of primary vaccine are required?

Answer 7

Germinal centers are generally short-lived with killed vaccines

Question 8

What is adjuvant?

Answer 8

Substance that enhance the immunogenicity of antigens

Required in inactivated vaccines

Question 9

What is the most common adjuvant in human vaccination?

Answer 9

Aluminum hydroxide

Question 10

What does adjuvant do?

Answer 10

Maintains a deposit of antigen at the injections site

Slow release of aluminum particles with antigen, which causes uptake by macrophages and immature DCs

Question 11

What correlates protection with inactivated vaccines?

Answer 11

Vaccine-induced immune responses that protect against disease

Question 12

What must happen in order for protection to occur in inactivated vaccines?

Answer 12

Antibodies must be present at the time of exposure to the pathogen

Question 13

How often are vaccine boosters require for inactivated vaccines?

Answer 13

Every 10 years

Question 14

What is an example of an inactivated vaccine?

Answer 14

DTP vaccine (diphtheria-tetanus-pertussis)

Question 15

What are characteristics of live vaccines?

Answer 15

Live vaccines can mimic a natural infection resulting in polyvalent immunity:
Neutralizing antibody
CD4 helper T cells
CD8 cytotoxic T cells

Question 16

Why do some vaccines require a booster?

Answer 16

For diseases in which antibody levels strongly correlate with protection, the decision for a booster is based on the persistence of antibodies and the incubation period of the disease

Question 17

Are seronegative individuals protected from Corynebacterium diptheriae toxin?

Answer 17

Not if they miss their booster. The incubation period (2-5 days) is so short that they would be sick by the time the memory cells are reactivated

Question 18

Are seronegative individuals protected from hepatitis B virus?

Answer 18

Yes. It has a long incubation period (45 days), so there is plenty of time for the reactivation of memory B cells

Question 19

Describe the persistence of antiboides

Answer 19

Long-lived plasma cells can have a finite lifespan
Long-lived plasma cells are not maintained after some vaccinations and therefore boosters are required
Memory B cells are maintained for decades after most vaccinations and natural infections