give examples of biological sourced materials
- bioactives- toxins
- bacterial polysaccharides
- proteins, peptides, glycoproteins
- lipids
- chemically modified substances- subunits
give examples of water soluble/dispersible adjuvants
- cholera toxin
- synthetic analogues of double stranded RNA (dsRNA)
- tetanus toxoid
give examples of O/W or W/O emulsion adjuvants
- W/O montanide ISA 720, vegetable oil
- Freunds complete adjuvant (CFA)- mycobacterium tuberculosis inactivated
- bacterial cell wall - Freunds incomplete adjuvant (IFA)- as CFA but lacks mycobacterium component
give examples of what can be used for emulsions in vaccines
- fats used: silicone oil, light paraffin
- emulsifiers: fatty acids, polysorbates
- microcrystalline wax, vitamin E
- dispersed phase 0.1-0.9 by volume
give examples of entrapment or absorption agent adjuvants
- alum, aluminium hydroxide anhydrous or hydrated
- silica
- latex
give examples of polymer particles and particulate adjuvants
- virosomes- virus structured liposomes
- haemophilus influenzae (Hib)
- bacterial flagellin
give examples of formulation stabilisers
- freeze drying cryoprotectants- eg sugars such as sucrose
- buffers- eg amino acids
- complexing and suspending agents- proteins such as human serum albumin
- relics- deactivation substrates
- delivery aids- gums and viscosifiers
- preservatives
- co solvents
- emulsifiers- tween
what are antibiotic stabilisers
- multi use vaccines need special formulation
- contain antibiotics eg. penicillin used to prevent fungal and bacterial infections - used in process septicity and hygiene- eg gentamicin
what are chemical inactivation agents
- chemical remnants- eg. cross linkers are often found in vaccines
- cross linkers remove pathogenicity and act as a disinfectant
- formaldehyde remnant, used to inactivate viruses
give examples of other inactivations
- application of heat >60 degrees/10hours
- low ph acid denaturation
- irradiation- uv, x ray
outline the process of purification of antigens
- eg hep B surface antigen
1. differential precipitation/solubilisation- ammonium sulphate, ph
2. ultracentrifugation
3. gel permeation chromatography
4. hydrophobic interaction chromatography
5. tested on enzyme linked immunosorbent assay (ELISA)
what is ELISA used for
- a colour indicating popular micro titre plate type analytic assay of a solution which uses a solid phase immobilised enzyme in an immunoassay to detect the presence of a vaccine antigen
- used in quality control
what are homotypic vaccines
one type of component- eg. Hib, flu
what are heterotypic vaccines
many types of antigenic components- eg. TB BCG
what is valency
refers to the number of strains used and therefore the universality
- bivalent is 2 strains
- quadrivalent is 4 strains
what is gardasil
- polyvalent vaccine for HPV virus
- protects males and females
- comes in prefilled syringe
- compatible with other vaccines
- contains viral proteins and aluminium adjuvant
give examples of GSK vaccines
- boostrix- tetanus
- fluarix- influenza
what is involved in quality control of vaccines
- sterility- free of live microorganisms
- chemistry standpoint- correct adjuvant, preservative and ph
- content- uniformity of content and potency
- safety- overdosing would carry no effective risk
- efficacy- each antigen present meets regulatory requirements
- virulence testing- via passaging in suitable model
- toxicity- no harm causing constituents
- stability test- shelf life, optimal storage determination
- chemical QC- moisture content
describe the dosage issues which can be found in vaccines
- variable- dose, dissipation, response, maturity of immune system
- constancy of formulation injection properties- viscosity, actives and excipients, stability profile
what are the 3 key factors that effective vaccine delivery is based upon
- efficient encapsulation of the active
- successful targeting of the active to a specific region of the body and pathogen
- successful release of that active in situ
