Vaccines Flashcards
What are antibodies? (production, storage)
Y-shaped, sticky molecules that are recognition devices. They stick to epitopes (or invading organisms) are unique, as in the body makes many different types of antibodies. Their production is random. The body stores a small amount of each antibody.
What are b-cells?
They carry antibodies. Each carries one antobody and recognizes only one epitope.
Body stores a small amount of each b-cell.
They get replicated when an immune response is triggered.
They can become memory cells after infection.
Generation of memory cells with age.
Less than 5% of b-cells in newborns are memory cells but more than 50% of b-cells in adults are memory cells.
What happens when the infection enters a cell?
B-cell cannot reach it. The production of t-cells (both killer and helper) is triggered. The killer cell recognises the MHC display while the helper cell sends the signal to destroy the cell with the infection within it.
Afterward, some t-cells become memory cells.
Small Pox and the first vaccine.
Had a 20-40% mortality rate. It disfigured 70-80% of its survivors.
Jenner realised milkmaids didn’t get small pox because they were exposed to cow pox that gave them immunity to small pox. The cow Blossom was the main source of cow pox. The cow pox simulated small pox and the body created memory cells against.
What is variolation?
Purposely exposing oneself to a virus when they are strong enough to survive it.
The Anthrax vaccine.
Discovered by Louis Pasteur. He heated the bacteria - weakened it - which only gave rise to a mild infection that would generate memory cells and impart immunity.
A second “booster” shot was necessary to generate more memory cells.
Polio and its 2 vaccines.
1% is paralytic. President Roosevelt suffered from it.
The Salk vaccine used a dead virus and required an injection. One batch of this vaccine was defective.
The Sabin vaccine used a weakened live virus and was taken orally, it did not require a booster.
Influenza colds and vaccines.
Infects 5-15% of population. It mutates every year. So researchers make an educated guess for the vaccine.
The influenza vaccine uses a dead virus.
Its main side effect is an egg allergy since it is manufactured in them.
What are adjuvants?
They stimulate the immune system which means that more memory cells are created. This makes a booster less necessary.
Adverse effects of vaccines.
Mostly minor: sweeling, fever, headache
Can have a rare allergic reaction.
Can cause disease, this is VERY rare.
Why is it important to continue vaccinating?
The unvaccinated keep the virus alive. Herd immunity is important when a virus hasn’t been eradicated.
Cervical cancer and HPV vaccine.
Guardasil, the HPV vaccine, uses a protein fragment from the virus.
The vaccine only works if one is uninfected.
