Immunology Two Flashcards
What is the role of the immune system?
Protect body from harmful substances, germs and cells that can make someone ill
What makes up the immune system?
Organs
Tissues
Cells
What can the immune system do?
Identify threat
Mediate attack
Eliminate pathogen
In some cases, remember pathogen in case attack happens again
What does a prolonged immune response lead to?
Chronic inflammation
What are the two branches of the immune system?
Innate
Adaptive/acquired
What are features of the innate immune system?
Immediate
Non-specific
No memory
What are features of the adaptive immune system?
Takes days to weeks
Highly specific
Has a memory
What does it mean to say the innate immune system is non-specific?
Can distinguish a human cell from an invader but cannot distinguish an invader from another invader
What is the first line of defence in the innate immune system?
Physical barriers
Cells lining the skin, cilia in airways, mucous membrane
What is the second line of defence in the innate immune system?
Physiological barriers
Saliva, flushing action of sweat and tears
What do the physical and physiological barriers do?
Stop infection from entering the body
What immune system is the complement system a part of?
The innate immune system
What is the complement system?
The complement system is made up plasma proteins that induce a series of inflammatory responses to fight infection.
What are the 11 steps in the complement system?
- Pathogen with antibodies enters the system
- Antibodies recognise antigens and bind to them. Antigen-antibody complex formed.
- C1 binds to antigen-antibody complex.
- C1 activation causes C2 and C4 to split.
- Part of C2 and C4 come together to form C3 convertase.
- C3 convertase splits into a small and larger section - C3a and C3b.
- C3a will fan out and attract more lymphocytes to the area.
- C3b will bind to the surface of the pathogen, marking it for destruction.
- C3b causes C5 to split into C5a and C5b
- C5b joins with C6-9 to from membrane attachment complex which attaches to membrane of pathogen, forming a hole in it.
- Water gushes into pathogen, forcing it to break apart.
What does it mean to say the adaptive immune system is specific?
The cells of adaptive immune system have receptors that differentiate one pathogen from another by their unique ports called antigens.
What does it mean to say that the adaptive immune system is diverse?
Can recognise an infinite amount of specific antigens and make a specific response against each of them
What is the advantage of the adaptive immune system?
Has a memory
Whats is the disadvantage of the adaptive immune system?
Takes days to weeks to work
How does the adaptive immune system have memory?
Each time the adaptive immune system sees a pathogen, they massively proliferate.
When that adaptive immune system sees the same pathogen, they massively proliferate again, resulting in a faster and greater response.
Most of these cells are deleted, but the ones that stay are memory cells.
What do multipotent hematopoietic stem cells branch into?
Myeloid progenitor cells
Lymphoid progenitor cell
What do myeloid cells become?
Cells of the innate immune system
What are the cells of the innate immune system?
Mast cell
Dendritic cells
Macrophages
Monocytes
Granulocytes:
Basophil
Eosinophil
Neutrophil
Natural Killer cells
What cells are phagocytic?
Neutrophils
Macrophages
Natural killer cells
What are basophils, eosinophils and mast cells all involved in?
Response to allergic reactions
What cell initiates allergic reactions?
Basophils