Trigger 5: A vaccine?

Question 1

genetic susceptibility to the disease is mainly regulated by

Answer 1

genes in the HLA (MHC complex) locus

Question 2

New findings haves suggested that

Answer 2

enterovirus’ play an important role in the aetiology of T1DM

Question 3

if a vaccine could target specific virus’ that cause T1D

Answer 3

then incidence may decrease

Question 4

why cant we use an existing vaccine

Answer 4

• may not have enough capsid protein
• could trigger autoimmunity
• specific serotypes
• no one has developed a vaccine which recognises serotypes of enterovirus which affect the pancreas

Question 5

what could be targeted by viral vaccine

Answer 5

capsid or RNA- a targeted protein component

Question 6

targeted vaccination

Answer 6

could vaccinate those at highest genetic risk e.g. HLA mutations

Question 7

role of media in communicating science to the public- negative

Answer 7

o May lead to scaremongering
o May lead to patients demanding vaccines
- Stereotyping
- Increase in diabetes misrepresentation in the media e.g. people may think T1D is infectious

Question 8

role of media in communicating science to the public- positive

Answer 8

• could increase support for funding by the government

- If screening strategies are adopted, the media could help with advertisement and uptake

Question 9

what trial would have to be carried out to show that a vaccine prevents type 1 dibetes

Answer 9

prospective cohort - in animal model and then humans

Question 10

sample size of study

Answer 10

would have to be large

Question 11

nature of sample size

Answer 11

have to be vaccinated when babies (representative of UK population)

Question 12

challenge of this type of study

Answer 12

• have to be long (people can get T1D in 50s)
• dropout
• have to be highly powered- expensive

Question 13

does the scale of the problem warrant such a study

Answer 13

potentially not- could think about screening for babies with T1D specific mutations e.g. HLA

Question 14

safety considerations of trial

Answer 14

Would have make sure the vaccine was tested in animals models and then a group of healthy adults, to ensure that the vaccine didn’t cause any adverse reactions

Question 15

practical considerations of trial

Answer 15

• Will be hard to convince potentially hundreds of thousands of parents to give permission to vaccinate their children
• Parents are already untrusting of vaccines
  o For vaccinations to be effective 95% of population need to have it
• Practicality of following participants up for such a long period of time- withdrawals (due to onset taking place between the ages of 0 to +50).

Question 16

is it possible that some virus’ could protect against type 1 diabetes

Answer 16

The hygiene hypothesis suggests that exposure to microbial agents may be beneficial for the development of a balanced immune system and its ability to maintain self-tolerance.

Question 17

infection by which pathogens have been showed to reduce incident elf T1D

Answer 17

by LCMV, enteroviruses, helminths, salmonella have been showed to significantly reduce T1D incidence.

Question 18

heritability of T1D

Answer 18

Although some genetic predisposition is associated with T1D, this association is regarded as weak

Question 19

in monozygotic twins the concordance rate is

Answer 19

well below 50%

Question 20

the disease also occurs in individuals who

Answer 20

carry protective genetic variations

Question 21

those genetically predisposed to mount a large response to virus

Answer 21

are more at risk of amounting an autoimmune response which trigger T1D

Question 22

why is T1D not an infectious disease

Answer 22

it is the human response to an enterovirus which can trigger T1D via autoimmune response

Question 23

possible side effects of vaccine

Answer 23

• Vaccination could make someone more sensitive to virus

- Adverse reaction

Question 24

in T1D we are talking about

Answer 24

polymorphism and not mutation