Ward Lectures Flashcards
What is the Latin name for the cowpox virus
Vaccinia
What was the vaccine used to treat smallpox, developed by Jenner?
Pus from cowpox-infected cows
List 5 characteristics of the perfect vaccine
- 100% safe
- single dose
- 100% effective - works on everyone
- easy administration
- stable for long periods of time/durable in immunity
List 3 types of vaccines common up till 2000s.
- Live-attenuated vaccines
- Subunit vaccines
- Whole-inactivated pathogens
What was Jenner’s intellectual leap in vaccine development.
Cross species protection is possible.
What was Pasteur’s practical leap in vaccine development?
Microbes need to be isolated to make vaccines
List 7 factors that drove vaccine development
- fear of human suffering
- sterility
- egg culture (cell culture)
- tissue culture
- molecular biology
- modern immunology
- germ theory
List 6 new types of vaccines:
- Subunit + multivalent vaccines
- Peptide vaccines
- combination vaccines
- cellular vaccines
- Transmission blocking vaccines
- Conserved proteins
What are multivalent vaccines?
Aka multivalent subunit vaccines, immunizes against 2 or more strains of the same microbe or against 2 or more microorganisms
What are combination vaccines?
Protects against 2 or more diseases or against 1 disease caused by multiple strains of the same microbe
What are cellular vaccines?
Remove tumour and DCs and prime DCs outside the body using antigens from tumour, then reinsert them so they mount a stronger response against tumour
What are peptide vaccines?
Peptides used to specifically stimulate CD4 or CD8 cells
Give 2 examples of viruses that mutate all the time and give a strategy to protect against them
HIV, HCV
Used conserved proteins for cross-protection (make vaccine found in many microbes so immune system will recognize subsequent attacks)
Do all vaccines prevent bacteria/viruses from infecting?
No, some vaccines transmission-blocking.
Parasitic stage for causing infection is different from the stage that transmits the disease. By targeting the transmission stage (mosquito to human), can prevent the disease stage altogether
What was the first adjuvant?
aluminum salts aka alum
What do adjuvants do?
Stimulate Th1, Th2, combined immune responses, etc
T or F: PAMPs may be used as adjuvants. If true, give an example
T, cholera toxin B
What are DNA vaccines?
An intracellular vaccine delivery method
List 3 new ways vaccines can be delivered, instead of a simple injection
DNA vaccines
Vesicles
Chimeric viruses, bacterial vectors
Leishmania infection model: susceptible mice can be made resistant against Leishmania if given ___ and ___
anti-IL4
IFNg
These promote a Th1 response that will clear the infection
What is DC cross-priming?
- Dogma used to be that antigens will only elicit CD4 response
- Ag are presented on DCs, which present Ag to MHCII –> CD4
- If you prime DCs, they can present Ag to MHCI
How can priming the innate immune system affect vaccine results?
Instead of mediating humoural immunity only (only Ab production), can stimulate cell-mediated immunity
T or F: innate immunity directs the direction of humoral and cell-mediated response
T
Why are PRRs being used in vaccines?
They recognize Ag, which will prime the innate immune system, which directs the adaptive immune system
Name a method in which Ag may be delivered into body as adjuvants
Using virus-like particles
Name 4 novel uses for vaccines
- contraception
- target tumours (cancer vaccines)
- inflammatory conditions
- target intracellular pathogens
Name 3 goals in the preclinical trial
- grow + isolate microbe in cell culture/animal models
- toxicity studies
- determine correlates of immunity
What is the goal of Phase I trials?
Focus on safety
First injection into humans
Monitor subjects
What are the goals of Phase II trials?
Dose escalation
Determine efficacy (Ability to produce desired result; how well the vaccine works)
Studies in special populations
What are the goals of Phase III trials?
Challenge studies (give vaccine, then infect) Field efficacy trials (real life testing)
Do vaccines eliminate bacteria?
No, they eliminate their toxicity
Why are some antibiotics against Rikettsia unsafe?
Genetics of Rickettsia microbe is very similar to that of our mitochondria
T or F: Antibacterials can be used to kill parasitic species instead of anti-parasitic drugs
T - some parasites live in symbiosis with bacteria, therefore removing the bacteria will also eliminate the parasite
T or F: Ab are effective against intracellular pathogens
F
What are the 4 goals of vaccination?
- eradicate organism
- prevent infection and colonization
- prevent consequences of infection
- modify disease
List 2 difficulties in making a bacterial vaccine
Often cannot grow the bacteria
Bacteria needs to remain unchanged despite repeated passages
List 3 requirements in making a bacterial vaccine
- avoid making the disease worse
- know which immune response the vaccine targets
- need to be able to grow and isolate the microbe, and it must stay the same despite repeated passages
T or F: losing humoral immunity is extremely lethal
F - you cannot make Ab, but Ab are not necessary; innate and cell-mediated immunity can take care of most viruses, intracellular bacteria, and most tissue protozoa
T or F: cellular responses are required for intracellular microbes/pathogens
T
T or F: vaccines are available for intracellular and extracellular pathogens
T
What type of structure does tetanospasmin have?
Tetanospasmin = toxin
A+B structure
What does the A part of the tetanus toxin do?
Inhibits GABA and glycine (inhibitory NT)
What does the B part of the tetanus toxin do?
Binds disialogangliosides
Define toxoid. Where are toxoids used?
Attenuated toxin; antigenicity is maintained, but is non-toxic
Used in vaccines
What are toxoid vaccines?
Vaccines that use an attenuated form of a toxin to target toxins
T or F: S. pneumoniae has a polysaccharide capsule
T
Why are Ab essential for the opsonization and phagocytosis of S. pneumoniae?
Because of the capsule
