lecture 11 Flashcards
what is passive immunity?
-short lived
-when given antibiotics instead of body responding itself
-newborn babies protected due to antibodies passed down from mothers via placenta
what is active immunity?
-long lasting
-involves immunological memory
-secondary and primary response
what is measles?
-highly infectious viral disease
-rash and fever
-ear infection -> hearing loss, pneumonia
what are requirements of effective vaccine?
-safe
-high level of protection
-long lasting protection
-right response
-low cost
-stable
-easy to administer
what are the 5 main types of vaccine?
- inactivated - dead organisms
- attentuated - live but viral removed
- subunit - protein fragments
- toxoid - bacterial toxin
- conjugate - low antigenic property bound to high antigenic property
example of dead/inativated vaccine and how works?
-salk polio vaccine
-may have side effects
-important antigens must survive killing
examples of live vaccines
- vaccinia (small pox)
- sabin (polio)
- MMR (measles, mumps and rubella)
- BCG (tuberculosis)
what are the pros of live vaccines?
-single dose effective
-can be given by natural route
-may induce local and systemic immunity
what are the cons of live vaccines?
-possibility of contamination
-susceptible to inactivation
what is polio?
-caused by enterovirus
-spread through faeco-oral route
-positive sense RNA thats translated into large polypeptide cleaved post translationally
example of subunit vaccine and how it works?
-hepatitis B
-tetanus toxoid - inactivated form of protein exotoxin secreted by the bacteria
example of conjugated vaccine and how it works?
HiB - haemophilus influenzae type B
-capsular polysaccharide conjugated to a protein
-converts thymus independent TI-2 polysaccharide antigen to thymus dependent form so young children can respond
what is reverse vaccinology?
-whole genome screening to identify proteins that could be used as vaccines
what are adjuvants?
-substance administered with antigen to promote immune response
-provide immunostimulatory properties
what is the action of adjuvants?
-activate dendritic cells via TLRs or NOD like receptors
-cause release of endogenous danger signals
-stimulate release of chemokines/cytokines