SciVaxx Flashcards
How long does it take for antibody response when vaccinated?
→5-7 days
How long does it take for gull response when vaccinated?
→2 weeks
How long does it for full protective response when vaccinated?
→7 days
What type of response for polio?
→antibodies
What type of response for tuberculosis?
→cell mediated
Where does response have to be induced for influenza?
→mucosal sIgA
Where does response have to be induced for yellow fever?
→systemic
What is a parenteral vaccine?
→given by injection
What are oral vaccines processed by?
→mucosal associated lymphoid tissue (MALT) - good IgA production
What is the incubation period for cholera?
→short
Which antibody is found in breast milk?
→sIgA
What are monotypic pathogens?
→Surface antigens have remained the same to date.
→Vaccination or infection gives lifelong immunity
→eg. measles
What is antigenic drift?
→accumulation of mutations in genes that code for virus surface proteins with time
What is antigenic shift?
→recombination of viral strains to produce a different subtype with a mixture of surface antigens from the original strains
How are live attenuated vaccines made?
→serial culture in foreign host ‘passage’ e.g. Measles: 10 years of serial passage in tissue culture to transform wild virus into attenuated vaccine virus
→chemical mutagenesis and selection of phenotypes e.g Salmonella typhi TY21a
→genetic engineering to create knockouts lacking genes for virulence e.g. Vibrio cholerae
→Live attenuated vaccines can be useful for producing CTL memory cells as they can infect APCs
What are some dangers with live attenuated vaccines?
→reversion to virulence
What do live attenuated vaccines require?
→cold chain to keep them alive
How are inactivated organism vaccines made?
→Killed with heat or chemicals e.g. formalin or β-propiolactone
What do killed vaccines require?
→booster for continued protection
Examples of live attenuated vaccines
→BCG,
→polio
→MMR
Examples for killed vaccines
→pertussis
→polio
What are the types of subunit vaccines?
→- proteins (often surface antigen e.g. Hep B)
→ toxoids (diphtheria; tetanus)
→peptides (synthetic) e.g. M-001 Influenza vaccine being trialled
→polysaccharide poor antigens
What molecules on bacteria is poorly recognised by children under 2?
→polysaccharide
What are the disadvantages of bacterial capsular polysaccharides as vaccines?
→short term memory
→no T-cell immunity
How is immunogenicity enhanced in capsular polysaccharides as vaccine?
→protein conjugation
→polysaccharide from bacteria and conjugate to a carrier protein
→taken into the cell and peptides presented to TH cell to produce antibody response and memory B cells
Examples of capsular polysaccharide vaccines
→MenC
→Hib
What are vaccine adjuvants?
→Chemicals added to vaccine to make them more immunogenic
→ promote uptake and antigen presentation
stimulate correct cytokine profiles
Example of a vaccine adjuvant
→Aluminium salts (Alum
→form trapped particles (depot)
→slow release of antigen
Why is it so difficult to produce a vaccine for HIV?
→High mutation rate
→Best way to do this is with an attenuated live vaccine but danger of reversion to virulence (especially with high mutation rate)
What are passive vaccine treatments?
→Passive immunity: maternal transfer.
→Treatment with antibody from another source: serum
→Prophylaxis and/or treatment Rapid Short effect
Describe rabies post exposure treatment
→injection with antibodies from serum of individuals who have been vaccinated against rabies into the wound site. HRIG – human rabies immunoglobulin
