13: medicines Flashcards
Active immunization:
- preventive method - most widespread form of control viral diseases and prevent economic losses - drawback: coexistence with the virus –> most vaccines do not prevent infection!
General rules about immunization against viral diseases:
- inhibitory effect of maternal antibodies - negative phase - vaccination schedules - avoid immunosuppression
Vaccine types:
- monovalent - polyvalent
Types of live virus vaccines:
* Virulent (wild type) virus vaccines
* Attenuated vaccines:
- Naturally occurring mutants (isolation)
- artificially attenuated viruses
- heterotypic vaccines
- virus-vectored vaccines
Virulent (wild type) virus vaccines:
different entry site e.g: contagious echtyma (orf)
Naturally occurring mutants (isolation):
Newcastle disease
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, Aujeszkys disease)
Heterotypic vaccines:
- Marek´s disease
- turkey herpes
- Small pox
- vaccinia virus
Virus-vectored vaccines:
introduction of anitgens into apathogen viruses
What is special about Inactivated (killed) vaccines?
the virus is not able to multiply! boostering is necessary!
Inactivated (killed) vaccines: - Inactivating agents?
- formaldehyde - ethylenimine, ethyl-ethylenimine (EI, EEI) - beta-propyolacton (BPL)
Inactivated (killed) vaccines: - adjuvants?
- slow antigen release, depo-effect
- immunostimulation
- AIOH3, saponine, oil
Comparison of attenuated and inactivated vaccines:
Subunit vaccines:
- containes only proteins responsible for neutralization
Production of subunit vaccines:
- purification after traditional virus production –> chromatography, iscom
- purification of proteins produced genetically, maipulated 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 waker immune response
Antiidiotype vaccines:
Epitope and paratope groups, “key and lock” theory.
Absolutely safe vaccines!
Production of Antiidiotype 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
