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Vaccine additives


correction: splenda has chlorine bound not aluminum

great website for ingredients of vaccines, info on legislation, etc.
http://www.vaccinesafety.edu
covers: excipients, allergens, thimerosal
thimerosal used in processing and removal may be incomplete

additives = anything added, not required to tell unless it's allergen or adjuvant!
component = preservatives, adjuvants, stabilizers (some but not all on product insert)

FDA REQUIRES DISCLOSURE OF
preservative used and concentration
known sensitizing agent
type and amount of ABX
inactive ingredients if they are a safety factor (gray area)
adjuvant
source of product
ID of microorganism and method of inactivation

PRESERVATIVES
to prevent growth of bact/fungi
must be added to multi-dose vaccines
must be non-toxic
phenol
benzethonium chloride
2-phenyoxylthanol
thimerosal merthiolate (p82)-->metabolized to ethyl mercury
thimerosal inactivates all viruses
ped doses must have less than 1 microgram of mercury
flu vaccine not considered child vaccine, mercury still in there
dT also not considered child vaccine, it's a booster, mercury still in there
tetanus also has mercury

ADJUVANTS
components that increase immunogenicity
to help or to aid (Latin)
effect discovered in 1926
older vaccines less pure: endogenous adjuvant (LPS)
more pure-->less immunogenic
live vaccines don't contain or need adjuvants
types: aluminum salts (alum), MF59 (Europe), monophosphyoryl lipid A (being tested)
aluminum salts in most childhood vaccines (all but rotavirus)
how it works:
1) increase antigen uptake by APC's
2) drive Th1 or Th2 response (aluminum salts drive Th2)(new designed to drive Th1)
3) increase activation of DC's so they can express more CD86 (for T cell activation)

aluminum salt adjuvants
drives Th2
usu .85-1.14 mg/dose
max per WHO is 1.25 mg/dose
in blood 1 hour to 28 days post IM injection
longer stay in skin, 6-9 mo
SE's: macrophage myofascitis (MMF) macrophages filled with aluminum
authorities say no evidence that vaccine is causing it
SE's of aluminum poisoning: anemia, dementia, bone disease, constip

combination vaccines are not designed as a single unit, they are additive of several individual vaccines, so additives are cumulative (except DTaP)

MF59
stable droplets <250nm of metabolizable oil squalene and two surfatants
polyoxyethylene sorbitan monooleate and sorbitan trioleate
in an oil in water emulsion
more immunogenic than aluminum-->10x higher AB titers
currently in flu vaccine
investigating for childhood vaccines
may drive a Th1 (not proven)

MONOPHOSPHORYL LIPID A
component of LPS
effective after two doses (not 3)
causes production of Th1 cytokines (IL12, IL1, TNFa, IFNg, GM-CSF in adults)
only tested so far in kids over 24 mo

QS21
plant extract from soap bark tree in Chile
water soluble triterpene glucoside compound
used in vaccines being developed for HIV and malaria

STABILIZERS
designed to protect vaccine from heat and freeze drying
add bulk to make vaccine visible and substantial
common ingredients: sug, aa, prot, buffer
human serum albumin ??

MANUFACTURING RESIDUALS
micro-org inactivators: formadlehyde, glutaraldehyde, H2O2
formaldehye cannot exceed .02% (normal in human is 2.6 mg/L)

ANTIBIOTICS
streptomycin, polymyxin B, neomycin, gentamicin
affect the microflora of person
sensitizing substances
chicken protein, yeast protein, detergent, solvents, chelators, things used to grow
bacterial and cellular residuals incl endotoxin
worry: transmissible spongiform ecenphalopathies (prions)
no known purification that would take prions out

Merck is beginning to research in 6 month old children
this is first research on kids this young

arguments for safety of additives usu relate to oral ingestion
not same as injecting

SUBCU INJECTION
antigen carried to nearest LN
recommended for vaccines that are less immunogenic and inflammatory
with adjuvant a Th1 response is possible, otherwise Th2

INTRAMUSCULAR (IM)
antigen picked up by macrophages in muscle and carried to LN
used for highly immunogenic vaccines
muscle doesn't allow such a large response
site matters
rabies less effective if in glut not delt (dt fat??)
with adjuvant Th1 is possible, otherwise get Th2

ORAL
drives Th3 tolerance
need live attenuated for this to work
oral polio and typhoid given orally because they're alive
oral MMR not effective
intranasal inhalation (INH) must cross mucus membrane, lungs Th2 dominant
try to get Th1 but it Th1 healthy in the gut? NO
Zwickey not a fan or oral vaccines

INTRADERMAL
only vaccinia in US
BCG also has been delivered this way

INTRAVENOUS
develop Th1 this way
antigen delivered to spleen
doesn't seem to give good immunity, not long lasting

EFFICACY
vaccines don't guarantee protection
dependant on several factors: vaccine and dz
strain of organism: esp flu
controversy over timing (not too young)
worry about vaccination while breast feeding because mom's AB's neutralize vaccine
genetics/non-responders

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