types: live attenuated, inactivated/whole cell killed, toxoid, component vaccine
live attenuated
weakened by growing in cell culture (human, chicken, guinea pig, monkey)
egg allergy
good for Th1 response, long lasting response
single dose may confer long term immunity
no adjuvants are needed (aluminum)
preservatives (thimerosal) cannot be used because it will kill the live bug
can cause the infx it is intended to protect against
esp in immunocompromised
ex: MMR, OPV, varicella
inactivated and whole cell vaccine
cannot cause infx, agent is dead and cannot replicate
virus grown, extracted, purified, killed with formaldehyde but shape is maintained
in whole cell vaccine the bact is grown on agar plate then killed with form. or heat
allergy to eggs --> allergy to vaccines grown in eggs
ex: IPV, inactivated flu, DTWP
usu w/ adjuvant to boost immunogenicity
response is usu Th2
multiple doses needed to confer immunity
toxoid vaccines
tetanus, diptheria
treat toxins with head or chems to destroy dz causing ability
body makes ab's vs toxin
ex: diptheria toxoid vaccine (in DTP, DTaP, dT), tetanus toxoid vaccine
component or subunit vaccines
only part of the microbe
three types: acellular, conjugate (w/ polysaccharide), recombinant
acellular = only parts that stim best immune response (acellular pertussis in DTaP)
conjugate = polysaccharide coat linked to immunogenic protein from elsewhere
H. flu, pneumococci have polysacc coat
we don't respond strongly to polysaccharides (MHC doesn't hold them, it holds peptides)
(get T-cell independent response: tolerance)
so link these coat prots to proteins to get stronger/longer lasting response
proteins chosen usu toxoids we also want immunity to: diptheria, tetanus, neisseria
bystander effect confers immunity to both, though CDC doesn't consider it so
response is usu Th2
multiple doses needed to confer protection
usu administered with adjuvant (aluminum) to boost immunogenicity
ex: Hib, Pneumococcual
recombinant vaccines
most recent
made by inserting a plasmid containing the gene for the immunogenic antigen into common baker's yeast
yeast cells product the antigen which is harvested and purified
vaccines have a little yeast in them but no yeast DNA
adjuvant: aluminum
response usu Th2
multiple doses needed
ex: Hep B and Hep A
all contained thimerosal until 2001