L28 - Intro To Vaccination Flashcards
How was vaccination first discovered
Having cowpox decreased chances of acquiring smallpox
What is considered passive immunity? What are the 2 types
The transfer of antibodies from an immune to non-immune individual
Natural - mother to child via placenta or colostrum
Artificial - transfer of antibodies derived from blood of immune people
How is therapeutic anti-sera produced
- using donor animal
- it is immunised with non-lethal doses of an antigen
- induced immune response produced neutralising antibodies
- blood from donor animal is collected and antibodies r purified from the blood
What are the current applications of antibody transfers
- Rapid treatment during acute illness of patients
- Preventative measure
Pros and cons of antibody transfers
Pros
- quick acting
- support a deficient immune system
- beneficial to high risk individuals
Cons
- protection fades overtime
- intravenous injection
- serum sickness
- expensive
- complicated to manufacture
How are monoclonal antibodies produced
- Mouse challenged with antigen
- WBC (B cells) taken from spleen and fused with myeloma cells
- The replicate to produce Abs indefinitely
- Harvest monoclonal antibodies
Pros of monoclonal antibodies
- single specificity
- unlimited supply
- even Abs w rare specificity can be isolated
- Abs can be manipulated
How to humanise a mouse monoclonal antibody, why is it needed?
Immune recognises mouse antibody as foreign antigen so might cause serum sickness
Replace the CDR (complementarity determining region) of a human monoclonal abs w CDR derived from mouse monoclonal antibody
What is the modern way of making monoclonal antibodies that are easier
- directly from B cells
- phage display
- EBV transformation
- in vitro expansion and selection
What are the 3 principles of vaccination
- introduce immune system to pathogen in controlled environmen t
- cause immune system to remember the pathogen and respond to it
- enable effective clear of pathogen to prevent disease
What is the ideal vaccine
- long lasting immunity
- safe
- stable in field conditions
- easy to store and administer
- Single dose
- pathogen evolution proof
What is live attenuated vaccine
Pathogenic strains in which the virulent genes are deleted or modified
Why is live attenuated vaccine more effective than killed whole organism
More effective immune recognises folded proteins. Killed proteins are unfolded
What is the significance of eggs in traditional vaccine technology
When virus injected into eggs diff parts of the egg lets diff virus replicate
Limitations to traditional vaccine
- not all grown in culture
- live (safety for lab people)
- expense
- insufficient attenuation
- reversion to infectious state
- storage
What is the cons of using live attenuated and killed whole organism
- Needs to be stored cold
- Several doses needed
What is toxoid
Vaccine using toxin derived from the pathogen
Describe the use of subunit for vaccines? Pros n cons?
Subunit includes: purified protein, recombinant protein, polysaccharide, peptides)
Don’t use entire pathogen but components
Pros: no extraneous pathogenic particles
Cons: protein may differ when not in Situ, production can be expensive
Describe vector vaccine
Antigen genes inserted to vaccinia virus able to elicit neutralising antibodies
