intro to immunology Flashcards
(27 cards)
What are the two arms of the immune system?
INNATE (‘natural’) IMMUNITY and ADAPTIVE (‘acquired’) IMMUNITY
How quickly does innate immunity develop?
Rapidly (hours)
Describe the response of innate immunity to pathogens.
Reacts in a relatively non-specific way
What is the response rate of innate immunity upon repeated exposure to the same pathogen?
Always at the same rate
What is the primary characteristic of adaptive immunity?
Slow to develop (days) and very specific
What are the two types of adaptive immunity?
- HUMORAL IMMUNITY
- CELL MEDIATED IMMUNITY
What produces antibodies in humoral immunity?
Stimulated lymphocytes called B cells
Where are B cells mainly located?
Spleen and lymph nodes
What do antibodies do?
Attach to extracellular pathogens and label them for attack
Name some key players in the immune system.
- Cells: macrophages, neutrophils, lymphocytes
- Organs: thymus, bone marrow, spleen, lymph nodes, tonsils, Peyer’s patches
What are the two forms of immunization?
- Active immunization (e.g., Vaccination)
- Passive immunization (e.g., Antiserum to snake venom)
What is the principle of vaccination?
Each antibody recognises a different epitope on the antigen
What happens if a self-antigen is injected?
No primary or secondary antibody response observed
What is the outcome of repeated skin grafts from a strain A mouse to another strain A mouse?
0% graft rejection
What is the clonal selection theory?
Antigen ‘selects’ B cell displaying best fit receptor
Who were the pioneers of the first demonstration of antibodies?
Von Behring & Kitasato
What major observation did Edward Jenner make regarding cowpox and smallpox?
Milkmaids who contracted cowpox did not contract smallpox
What did Jenner hypothesize about cowpox fluid?
It might protect people from smallpox
What are some diseases targeted by vaccines in developed countries?
- Tetanus
- Diphtheria
- Pertussis
- Polio
- Measles
- Mumps
- Rubella
- HiB/meningitis
What percentage of mortality due to infectious disease is observed in the developed world?
~2%
What can cause a higher mortality rate from infectious diseases in some third world countries?
- Poor sanitation
- Water supply
- Malnutrition
- Insect vectors
- Limited access to medical intervention
What is the role of cytokines in the immune system?
Activate other effector cells
What is the function of cytotoxic T cells?
Target abnormal cells when in contact
What is the significance of self-tolerance in the immune system?
Can distinguish between ‘self’ and ‘non-self’
