Exam 2- Principles of Immunization

Question 1

what is the goal of active immunization?

Answer 1

generate long-lasting and protective immunization against a specific pathogen to prevent infection and/or disease by that pathogen and eliminates or decreases carriage and/or shedding of the pathogen

Question 2

what are the two main types of immunization?

Answer 2

active and passive

Question 3

capsular polysaccharide is the only antigen that protects against an extracellular pathogen and (transmitted by tick bite) that infects the liver, but no other organ. which response will be the most important for protection against the pathogen?

Answer 3

serum antibody response

Question 4

you would like to prepare a vaccine using the polysaccharide antigen. what do you conjugate it to?

Answer 4

polysaccharide antigen conjugated to a protein carrier with an aluminum phosphate adjuvant

Question 5

what are the advantages of active immunization?

Answer 5

generates humoral or both humoral and cell-mediated immunity
long term protection due to generation memory and plasma cells
does not lead to serum sickness

Question 6

what are the disadvantages of active immunity?

Answer 6

time (weeks) to develop immunity
fibrosarcomas can occur in cats- rare

Question 7

what does passive immunization involve?

Answer 7

transfer preformed antibodies against particular pathogen or toxin

Question 8

what are the two classes of passive immunization?

Answer 8

natural and acquired passive immunity

Question 9

when does natural passive immunity occur?

Answer 9

maternal antibodies transferred to fetus via placenta or colostrum

Question 10

true/false: acquired passive immunity is when purified monoclonal antibodies or immunoglobulins from a different individual are injected into an individual

Answer 10

true

Question 11

what is the advantage of passive immunization?

Answer 11

immediate benefits

Question 12

what are the disadvantages of passive immunity?

Answer 12

immunity is short-lived: 2-3 weeks
repeated administration from heterologous species can result in serum sickness

Question 13

do polysaccharide antigens require conjugation with a carrier protein? why?

Answer 13

alone, mostly induces IgM response: half-life 4-5 days, lack of help from Th cells with class switching
conjugated: effective IgG response, recruits Th cells for class-switching

Question 14

what is a conjugate vaccine?

Answer 14

vaccine of polysaccharide antigens conjugated with protein carrier molecule

Question 15

why is it important to know about the transmission route and disease pathogenesis of a pathogen?

Answer 15

to know what reaction a vaccine should induce: mucosal or systemic immune response or both

Question 16

what type of immunity is important for extracellular pathogens?

Answer 16

humoral immunity

Question 17

what type of immunity is important for intracellular pathogens?

Answer 17

both humoral and cell-mediated immunity

Question 18

how can a vaccine induce a long-lasting protective immune response?

Answer 18

long-lived plasma cells
memory Th and memory B cells
memory Tc cells
make antigen available to immune system for sufficient duration

Question 19

what are adjuvants used for?

Answer 19

decrease amount of antigen and reduce number of doses required to induce protective immunity
induce protective response more rapidly
increase rate of seroconversion in special populations

Question 20

what are the five mechanisms of action adjuvants may use?

Answer 20

increasing biological half-life of vaccines
upregulation cytokines and chemokines at site injection
increase antigen uptake and presentation to APCs
activation and maturation APC
activation inflammasomes

Question 21

what adjuvants are most widely used in human and veterinary medicine?

Answer 21

aluminum adjuvants

Question 22

what response do aluminum-containing adjuvants induce?

Answer 22

preferentially Th2 responses

Question 23

what adjuvants have been implicated in development of feline fibrosarcoma?

Answer 23

aluminum adjuvants

Question 24

what do water-in-oil emulsion adjuvants consist of?

Answer 24

heat-killed Mycobacterium tuberculosis in non-metabolizable oils

Question 25

what type of response does a complete Freund's adjuvant induce?

Answer 25

mostly Th1 incomplete: mostly Th2

Question 26

are injection site reactions common with water-in-oil adjuvants?

Answer 26

yes, fairly common

Question 27

what does the oil-in-water adjuvant MF59 consist of?

Answer 27

squalene oil Tween 80 and Span 85

Question 28

what type of response does MF59 lead to?

Answer 28

balanced Th1 and Th2 response half life is 42 hours

Question 29

what is required to form cage-like complexes?

Answer 29

saponin cholesterol phospholipid immunogen

Question 30

what vaccines is the adjuvant QS-21 used in?

Answer 30

feline leukemia virus (FeLV) canine Lyme disease vaccine

Question 31

from where are live attenuated or modified live vaccines derived from?

Answer 31

"wild" or disease-causing viruses or bacteria

Question 32

how are wild viruses or bacteria weakened or attenuated?

Answer 32

repeated in vitro culturing cold-adapted and temperature sensitive defined genetic modification mutagenesis by chemicals or irradiation

Question 33

is adjuvant required for live attenuated or modified live vaccines?

Answer 33

no

Question 34

can live attenuated or modified live vaccines convert back to virulent form?

Answer 34

yes

Question 35

who should not receive live vaccines, if anyone?

Answer 35

individuals with weakened immune systems

Question 36

are inactive or killed vaccines safer than live vaccines?

Answer 36

yes

Question 37

killed bacterial vaccines are also called "_____________"

Answer 37

bacterins

Question 38

what are the advantages of subunit or antigen vaccines?

Answer 38

very safe unable to revert back to cause disease with good adjuvant, can induce humoral or both humoral and cell-mediated immunity

Question 39

true/false: one advantage of a DNA vaccine is that antigen is presented by both MHC class I and MHC class II molecules

Answer 39

true

Question 40

why is an RNA vaccine safer than a DNA vaccine?

Answer 40

it poses no risk of disrupting cell's natural DNA sequence

Question 41

how does a vector vaccine differ from a live vaccine?

Answer 41

only a gene encoding for a protective antigen of a pathogen is inserted into an attenuated virus or bacterium

Question 42

when are autogenous vaccines used?

Answer 42

within a herd, using a pathogen obtained from an animal in the herd

Question 43

what types of hypersensitivity reactions can vaccines induce?

Answer 43

types I, II, and IV hypersensitivity reactions

Question 44

for maternal antibodies, what are the three possible mechanisms of antibody interreference?

Answer 44

antigen removal by macrophages B cell inhibition through epitope masking B cell inhibition through cross-link of BCR with Fc-gamma-RIIB

Question 45

what can repeated administration of antibodies from a heterologous species result in?

Answer 45

serum sickness

Question 46

are polysaccharide antigens in vaccines good at eliciting a cell-mediated response?

Answer 46

no