immunity and immune system disorders

Question 1

How does the immune system normally regulate autoreactive T and B lymphocytes to prevent autoimmune responses?

Answer 1

immune tolerance

Question 2

points on Haemolytic anaemia

Answer 2

• antibodies target antigens on the surface of RBC
• this binding leads to phagocytosis and engulf rbc
• cytotoxic released

Question 3

define Myaesthenia gravis

Answer 3

an autoimmune disorder where muscle cells weaken

Question 4

define Grave’s disease

Answer 4

an autoimmune disease where thyroid galnd makes too much

Question 5

define Systemic Lupus erythematosus (SLE) and their symptoms

Answer 5

autoimmune disorder that tell antibodies to damage skin, joints, lungs
- SLE can deposit immune complexes( immune response) in organs like kidneys :

• In the kidneys, the antibodies that target dsDNA can cause damage by triggering the complement system, and increased interferon levels can lead to inflammation in the body.

Question 6

define Rheumatoid arthritis

Answer 6

-an chronic autoimmune disease affects joints=inflammed

Question 7

what is rheumatoid factor?

Answer 7

an antibody that targets igG by accident (protein that fights of bacteria/viruses )

Question 8

what are the 3 steps on how the immune system detect and responds to infections and what has to be presented before all this process

Answer 8

T cells have to be presented by APC
- T cells have to bind to its specific receptor for activation to happen

1. APC (antigen-presenting cells) like macrophages engulf pathogens (bacteria/viruses)
2. antigen are shown on the surface of APC attached to MHC (Major Histocompatibility Complex ) = AKA now its antigen- MHC
3. T cells have receptors that identify these antigen-MHC so binding to APC can happen

Question 9

what is type 1 hypersensitivity?

Answer 9

1. immeidate= allergies (hay fever,astham and eczma)
   - antigen (allergy) binds to igE on mast cells
   - mast cells release histamine and heparin
   - histamine causes sneezing,itching
   - heparin= stops blood clotting

Question 10

what is type 2 hypersensitivity?

Answer 10

• antibodies target membrane compoennts leading to cell damage
• cell lysis happens

Question 11

Type 3 hypersensitivity?

Answer 11

• immune complex deposition
• antigen-antibody complexes are deposited in tissues
• leads to activation of complement and phagocyotosis= inflammation

Question 12

Type 4 hypersensitivity?

Answer 12

delayed hypersensitivity
- reaction delayed by T cells
T cells release cytokines(attracts immune cells- lymphocytes and macrophages) causing a repsonse to happen after a few days
- an example is tuberculin skin test