13. Lecture Flashcards
• Active immunization
viral vaccines
• preventive method
• most widespread form to control viral diseases and prevent economic losses
• drawback: coexistence with the virus
→ Most vaccines do not prevent infection!
general rules in viral vaccines/immunization against viral disease
- inhibitory effect of maternal antibodies
- negative phase
- vaccination schedules
- avoid immunosuppression
vaccine types
- monovalent
* polyvalent
live virus vaccines; Virulent virus vaccines
(wild type)
•different entry site
natural attenuated vaccines
•Naturally occurring mutants (isolation)
Artificially attenuated viruses
• serial passages (in alien host, in embryonated eggs, in
cell cultures)
• selection of thermo-sensitive mutants
• genetic modification (deletion mutants)
→ marker, DIVA vaccines (IBR, Aujeszky’s disease)
Heterotypic vaccines
are pathogens of other animals that either do not cause disease or cause mild disease in the organism being treated
• Marek’s disease – Turkey herpes
• smallpox – vaccinia virus
Virus-vectored vaccines
• introduction antigens into apathogen viruses
Inactivated (killed) vaccines:
→ The virus is not able to multiply
adjuvants (enhancing)
•slow antigen release, depo-effect
•immunostimulation
•AlOH3
, saponine, oil
boostering is necessary in inactivated vaccines
Route of administration in live and inactivated vaccines
live: natural/injection
inactivated: injection
Virus dose (~cost) in live and inactivated vaccines
live: low
inactivated: high
Number of doses in live and inactivated vaccines
live: single
inactivated: multiple
need of adjuvant in live and inactivated vaccines
live: no
inactivated: yes
Duration of immunity: live and inactivated vaccines
live: longer
inactivated: shorter
Antibody response: live and inactivated vaccines
live: IgG, IgA
inactivated: IgG
Cell-mediated response: live and inactivated vaccines
live: good
inactivated: poor
Heat instability in tropics in live and inactivated vaccines
live: yes
inactivated: no
Interference: live and inactivated vaccines
live: occational
inactivated: no
Side effects: live and inactivated vaccines
live: occational
inactivated: no
Reversion to virulence in live and inactivated vaccines
live: possible
inactivated: no
Contamination in live and inactivated vaccines
live: possible
inactivated: no
subunit vaccines
•contains only proteins responsible for neutralization
production of subunit vaccines
•purification after traditional virus production
→chromatography, iscom
• purification of proteins produced by genetically
manipulated bacteria or cells
• synthesis
→ maturation of the polypeptide!
advantages of subunit vaccines
- safe (without nucleic acid)
- opportunity for differentiation (ELISA)
- in experiments good efficacy
Disadvantages of subunit vaccines
- expensive
- only parenteral administration
- in vivo usually weaker immune response
Anti-idiotype vaccines
•epitope and paratope groups
(„key and lock” theory) (receptor parts)
–> receptor only, not the actual virus
•absolutely safe vaccines
production of Anti-idiotype vaccines
• animal species „A” immunized with viral antigen
→ anti-viral IgG „A” is purified
• animal species „B” is immunized with anti-viral
IgG „A”
→ anti-(IgG „A”) IgG „B” is purified
→Fab of IgG „B” ~ viral antigen
• usually with monoclonal antibodies
