Becoming Immune/vaccine Flashcards
What is passive natural immunity, what does it provide and what do antibodies do
Passive natural immunity is when antibodies are transferred through a natural means to another individual e.g breast feeding. Provides short immunity (as no memory cells made).
Antibodies will combat pathogens with complementary receptors, providing immunity. Once supply of antibodies stops, numbers will drop
What is natural active immunity
Active natural immunity is when B cells detect antigens as non self, which stimulates immune response. Antigens are naturally picked up e.g coming into contact with someone who has chicken pox. B cells differentiate into B effector and B memory cells. B effector cells produce antibodies to destroy current infection
B memory provide long term immunity (secondary immunity)
What is active artificial immunity
Active artificial immunity is when artificially given a ‘safe’ version of antigen to trigger immune response e.g toxin, killed bacteria. B cells detect antigens as non self, are activated and form B effector and B memory cells (provide long term immunity)
Why are there no symptoms when given vaccine
No symptoms during vaccines because they are given a ‘safe’ version of virus.
What must vaccine have and how can this be achieved
Vaccine must have 1 or more antigens that are found on pathogen or toxin they produce.
This can be achieved by:
Attenuated virus
Killed bacteria e.g whooping cough bacteria
Antigen bearing fragment of pathogen (part of pathogen containing antigen is broken off)
Harmless version of toxin
What is attenuated virus
Attenuated virus is weakened version of virus that are harmless
What is passive artificial immunity
Passive artificial immunity is used as a treatment against pathogen or to prevent development of pathogen after exposure
Person is given large dose of antibodies that circulate in blood destroying pathogen. E.g tetanus
Only short term (no B memory cells)
What is active and passive immunity
Active immunity is when antigens are given, triggering immune response.
Passive immunity is when antibodies are given, not antigen
How can someone with Ebola be treated
Ebola can be treated by:
Taking blood from Ebola survivor
Blood is centrifuged, separate blood based on density, blood plasma at top
In blood plasma there are antibodies and can be given to someone with Ebola. Donate to sufferer
B memory cells not in blood plasma, so
What are natural and artificial immunity
Natural immunity is when body comes across virus by chance,
Artificial immunity is when body is deliberately exposed to antigen
Why do levels of antibodies increase rapidly after reinfection
Levels of antibodies rapidly increase upon reinfection because
Of Secondary immune response, memory cells remain in blood and upon reinfection they are activated and plasma cells release antibodies upon reinfection with same antigen
