Vaccines Flashcards
What is the objective of a vaccine?
to stimulate the adaptive immune system to create MEMORY.
Which cells are produced with an antigen coming to a secondary lymph organ via the lymph or the blood?
Memory B cells
Which cells are produced when an APC presents the antigen on a MHC II?
Memory Helper T cells
Which cells are only produced when an INFECTED CELL pesents the antigen on MHC I?
Memory Killer T cells
What are the 6 features of effective vaccines?
Safe, Protective, Gives sustained potection, Induces neutralizing antibodies, Induces protective T cells, and be Practical
What does it mean for a vaccine to be safe?
The vaccine itself must not cause illness or death
What does it mean for a vaccine to be protective?
The vaccine must protect against illness resulting from exposure to the pathogen
What does it mean for a vaccine to give sustained protection?
The protection from the illness must last for several years.
What does it mean for a vaccine to induce neutralizing antibodies?
Some pathogens infect cells that cannot be easily replaced, neutralizing antibodies are essential for preventing infection of these cells.
What does it mean for a vaccine to induce protective T cells?
Some, especially intracellular, pathogens are more effectively dealt with by cell mediated responses.
What are taken into account with the practical considerations with the effectiveness of vaccines?
Low cost per dose, biologic stability, ease of administration, with limited number of side effects.
True or False: vast majority of vaccines have been developed by using the vast understanding of the immunological mechanisms that are used to induce immunity.
False: The vast majority of vaccines were developed empirically with little or no understanding of the immunological mechanisms used to induce immunity.
It is believed that most vaccines confer protection via _______ ________.
Neutralizing Antibodies (precise mech. is an active area of research) Antibody titers is used to assess the level of protection.
In addition to antibodies __ Cells may also play a key role.
T cells
Both antibody and T-cell responses seem to rely on the ______ immune system.
Innate
_______ is the process of eliciting a long lived state of protective immunity against a disease causing pathogen
Immunization
What are one passive and two active ways we can develop immunity
Passive: Transfer of preformed antibodies can confer immunity but it is temporary (mother to fetus or exogenous antisera)
Active: Exposure to the pathogen followed by recovery, or Vaccination (doesn’t always ensure immunity, B and T cells must develop)
True or False: In acute infections, natural infection and recovery ensures immunity (complete protection against reinfection.
False, in many acute infections including respiratory syncytial virus or malaria natural infection does not give complete protection against reinfection.
It is especially difficult to combat pathogens with which characteristics:
a. mutate rapidly
b. exist as multiple serotypes
c. cause persistent or latent infections.
d. all of the above
d. all of the above
