CAE- L7 Vaccine

Question 1

What are the 2 types of natural immunity?

Answer 1

– Active - natural recovery from infection

– Passive - maternal antibodies

Question 2

What are the 2 types of artificially acquired immunity?

Answer 2

– Passive immunisation

– Vaccination (active immunisation)

Question 3

What are salvia routes for possible immunity to dental caries?

Answer 3

• sIgA
• IgG, IgM
• Leukocytes
• C3

Question 4

What are crevicular fluid routes for possible immunity to dental caries?

Answer 4

• IgG, IgM, IgA
• Complement
• PMNLs
• T-lymphocytes
• B-lymphocytes
• Macrophages

Question 5

What is vaccination?

Answer 5

Administration of material of ‘microbial’ origin (vaccine) to a susceptible person to stimulate their immune defenses

Question 6

what does vaccination stimulate?

Answer 6

long lasting protection against a specific disease

Question 7

Describe the Bowen (1969) experiment.

Answer 7

• Live cariogenic strain of S.mutans
• Injected intravenously
• Monkeys fed cariogenic diet
• Assay after 1 year:
>Control (n=3) 38 cavities 13 early lesions
>Vaccinated (n=3) 6 cavities 4 early lesions

Question 8

Describe the Bowen (1975) experiment.

Answer 8

•  Homogenized (broken) cells of S. mutans 
•  Injected into the oral mucosa
•  Monkeys fed a cariogenic diet
•  Assayed after 5 years:
>Control (n=5) 64 cavities 
>Immunized (n=4) 0 cavities

Question 9

Describe the result of subcutaneous inoculation using mutans streptococci in rats.

Answer 9

– induced salivary secretory IgA
– inoculated with bacteria & reduced level recovered
– reduced carious lesions

Question 10

Describe the result of feeding live bacteria in rats.

Answer 10

– stimulated secretory IgA

– no detectable specific serum IgG

Question 11

Describe what happens in the lehner et al .

Answer 11

•  Rhesus monkeys
•  Human type diet
–  (including Mars bars!)
•  Killed S. mutans
•  1 subcutaneous injection
•  Smooth surface & fissure
caries reduced (60-80%)
•  S. mutans reduced
• Specific IgG levels increased

Question 12

Name 3 antigens of mutans streptococci .

Answer 12

• Protein antigens (Antigen I/II)
• Glucosytransferase (GTF)
• Glucan binding proteins (Gbp)

Question 13

What happens if antibodies bind to antigens on mutans streptococci?

Answer 13

they acts as blocking peptides -interferes with the tooth surface even before rest of immune system reacts

Question 14

What is the basis lehner (1980)?

Answer 14

• immunization with a purified protein
• Streptococcal antigen I/II
• Monkey experiments:
>4 sham-immunized with saline
>3 injected subcutaneously with formalin-killed S. mutans
>3 injected subcutaneously with 1 mg antigen I/II

Question 15

what was the caries mean scores for the 3 monkeys in lehner (1980)?

Answer 15

> Sham - 9.5 (smooth), 4 (fissure) ,13.5 (total)

> S. mutans cells- 2.7(smooth) , 1 (fissure), 3.7 (total)

> Ag I/II - 2.7(smooth) , 1.3 (fissures) , 4 (total)

Question 16

Describe the lehner experiment (1985).

Answer 16

• Passive immunisation (monkeys)
– monoclonal antibodies against Antigen I/II
• Applied topically to the deciduous teeth

Question 17

What is the result of the lehner experiment (1985)?

Answer 17

• Reduced colonisation by S. mutans.
– dental caries eliminated
– control monkeys: high levels of S. mutans and dental caries

Question 18

what is the role of antigen I/II (mutans strep antigen)?

Answer 18

– surface adhesin
– block receptor for
attachment to pellicle

Question 19

what is the result of subcutaneous injection or intranasal of antigen I/II?

Answer 19

Preclinical reduction in MS

Question 20

what is the result of passive administration of antigen I/II?

Answer 20

interferes with recolonisation by MS

Question 21

Describe the structure of glucosytransferase GTF (mutans strep antigen) and the roles.

Answer 21

•  2 GTFs
–  make soluble or insoluble glucans
•  N-terminus
–  2 catalytic domains
•  C-terminus
–  glucan binding motif
•  MAP peptides using N and C terminus inoculated
–  inhibit GTF activity
–  protect rats from caries

Question 22

what do surface proteins of GTF bind?

Answer 22

– Bind glucans produced by catalytic
enzymes

– GbpB (GBP59) immunisation
• protects rats
• reduces colonisation by S. mutans

– MAP peptides to GTF & GbpB
• enhances immunogenicity
• extended effect to S. sobrinus

Question 23

what is the result of the combination of S. sobrinus GTF and water soluble gluons?

Answer 23

preclinical caries reduction

Question 24

what is the result of the combination of GTF and antigen I/II?

Answer 24

– Inhibition of S. mutans adherence in vitro
– Suppression of S. mutans colonisation in vivo
– Clinical increase in IgA nasal & saliva secretions

Question 25

what is the result of the combination of di-epitopic GTF and MAP?

Answer 25

– (catalytic domain & glucan binding domain) | – Preclinical reduction in experimental caries

Question 26

what is the result of the combination of di-epitopic GTF and GbpB MAP?

Answer 26

Preclinical reduction in experimental caries

Question 27

What does active immunisation do?

Answer 27

• Ellicit Antibodies – Immunological memory – Specific – Good experimental evidence

Question 28

What does passive immunisation do?

Answer 28

``` • Exposure to Antibodies – Safe – Murine monoclonal – Transgenic plant – Egg yolk – Bovine milk ```

Question 29

What are the components that effect active immunisation?

Answer 29

* Identification of best antigenic material * Administration of vaccine * Timing * Necessity

Question 30

What is the identification of the best antigenic material?

Answer 30

– Combination antigen | – Advantage of more than one target

Question 31

What is the administration of vaccine?

Answer 31

– Local (salivary antibodies) | – Intranasal, tonsillar

Question 32

What is the timing?

Answer 32

– Appropriate target group 12 months | – Before colonisation & immunocompetent for IgA

Question 33

What is the necessity factor?

Answer 33

• Disease is not life threatening: – Common disease, pain, disfigurement, lost productivity – Disproportionate effect on socio-economic classes – S. mutans link to endocarditis

Question 34

What are alternative approaches of controlling caries?

Answer 34

``` – Fluorination – Topical fluoride application – Dental sealants, – Brushing, flossing, regular visits to dentist – Dietary sugar/sucrose restriction ```

Question 35

Describe the alternative - synthetic peptide therapy.

Answer 35

``` • Identify inhibitor of SA I/II • Peptide that corresponds to aa 1025-1044 • Blocks binding • p1025 given as topical application to human volunteers • reduced recolonisation by S. mutans but not Actinomyces species ```