Lecture 12 Flashcards
(10 cards)
list the general requirements of effective vaccines
requirements of effective vaccines
- safety, vaccine doesn’t cause illness or death
- efficacy
- extracellular bacteria-ab are important
- intracellular bacteria-effective cell-mediated immunity important
- point of entry- mucosal immunity for organism the enter via mucosal sites
- protection against exposure to live pathogen
- give sustained protection sometimes multiple vaccinations are required
- induces neutralised ab; prevention of infection
- induces protective T cells
- few side effects
List the types of vaccines
types of vaccines
-living organism can be fully virulent which causes a strong response like swollen lymph nodes or attenuated (reduced virulence), vectored vaccines (use live organism, carrier to deliver ag from other organism)
-inactivated virus or bacteria, killed whole virons or bacteria
-subunit vaccines; bacterial toxoids or extracts, recombinant ag of virus/bacteria, other types DNA
-Univalent (used to vaccinate against 1 strain)/multivalent (used to vaccinate against 2 or more strains)
core vaccines v non core
Types of live virus
types of live virus
- modified live virus
- inactivated virus (killed or inactivated)
- purified subunits
- recombinant product
- DNA vaccine
For live vaccines; attenuation of virulence, define it
- the level required
- an example
live vaccines; attenuation of virulence
attenuation= reduction of virulence so they no longer cause disease
there are issues with attenuation you put get it just right or you get underattenutation=residual (left over) virulence or overattenuation= ineffective
a virus can be cultured in a species cells it won’t infect it, the virus will mutate and no longer be able to infect the og host
Explain what a killed vaccine is when its inactivated
Killed vaccines; inactivation
-killed organism must remain antigenically similar to living organism
For a live and Killed vaccine state the following
- storage
- cause disease
- required amount
- characteristics
- will it effect young and pregnant animals
- amount required
killed vaccines
-more stable for storage
-unlikely to cause disease
-no risk of reversion (being infective again)
-doesn’t spread to other animals
-will not cause shedding or ag nor cause disease
-prtoection mayn’t be acquired until 1-2 weeks after a booster vaccine in even
-require multiple vaccines
live vaccines
-cold chain required to maintain quality of vaccination
-mimic natural infection
-fewer doses, smaller does
-long lasting protection
-adjuvants unnecessary
-less chance of hypersensitivity reaction
-not suitable for pregnant or young animals
-theoretically the live vaccine can cause spreading of the virus
Explain a recombinant product vaccine
recombinant product (ag) vaccine
- good producing large amounts of purified ag
- isolate DNA from virus which is inserts into cloning factor, recombinant protein is expressed and purified
- purified proteins are combined with adjuvants to enhance immunogenicity
For DNA vaccines explain what is injected when occurs, its benefits
DNA vaccine
infect DNA rather than protein
vaccine Ag gene cloned into plasmid, which is injected into muscle or skin and then up by the host cell
DNA is transcribed within the host cell and translated into vaccine Ag
the plasmid DNA acts as adjuvant
improves efficiency by encapsulating DNA
For adjuvant define it, when they are required what they target what may occur how depot adjuvantes, particulate adjuvant and immunostimulatory adjuvants work
Adjuvants maybe added to enhance the immune response
this is required for subunit vaccinates because they don’t produce a stronger enough response
may target TLRs
granulomas may form around the injections site because there is more of a reaction
depot adjuvantes->slow removal of ag-> prolonged immune response
particulate adjuvant enhance ag presentation-> enhance cytokine production by ag presenting cell-> enhanced Th cell response-> enhanced cell-mediated immunity
immunostimulatory adjuvants-> stimulate TLRs->enhance cytokine production by ag presenting cell-> enhanced Th cell responses-> enhanced ab production
How are TLR agonist can be used as adjuvants
How are TLR agonist (stimulator) can be used as adjuvants
Pathogen associated molecular patterns, PAMPs, leukocytes like macrophages, dendritic cells have receptors that recognise the PAMP which are Pattern recognition receptors PRRs, these related to bacteria are Toll like receptors TLRs
which trigger innate and adaptive immune response
-binding of pathogen derived molecules to different immune sensors which activates innate pathways
