bio 8D

Question 1

what is activation immunotherapy?

Answer 1

refers to the amplification of the action of the immune system/an immune response

Question 2

what is suppression immunotherapy?

Answer 2

refers to the inhibition/prevention of the action of the immune system/an immune response

Question 3

explain the treatment of immunotherapy: dendritic cell therapy

Answer 3

• Dendritic cells are primed with tumour-associated antigens (TAA)
  
  • This activates lymphocytes: priming them to kill any cells expressing the tumour antigen
    - Priming can be achieved by vaccination with TAA’s OR removing dendritic cells from the body and priming them with TAA’s externally before infusing them back into the patient

Question 4

explain the treatment of immunotherapy: CAR-T therapy

Answer 4

• T cells are modified to recognise and destroy cancer cells
• T cells are extracted from the patient and a gene is added that codes for an antigen receptor
  
  • The protein is made by a cell and inserted into its membrane (allows it to recognise cancer cell antigens)
• These cells with chimeric antigen receptors (CAR) are then reintroduced inti the patient and seek out and destroy cancer cells

Question 5

explain the treatment of immunotherapy: antibody therapy

Answer 5

• Involves the creation and use of antibodies to stimulate and enhance the functioning of the immune system (often used in the treatment of cancer)
  - Antibodies used are typically monoclonal antibodies

Question 6

explain the treatment of immunotherapy: cytokine therapy

Answer 6

• Involves the use of immune signalling molecules (interferons and interleukins) to modulate the effect of the immune system

Question 7

what are monoclonal antibodies?

Answer 7

• Artificially produced by stimulating the production of B-cells in mice injected with the antigen (the B-cells produce an antibody against a specific antigen)
  - Highly specific + can be produced in large quantities

Question 8

how are monoclonal antibodies used in fighting cancer?

Answer 8

the antibodies produced are injected into the body and attach to cancer cells, causing Natural Killer (NK) cells to appear and activate by binding to the cancer cell (through the antibody + antigen), releasing enzymes and causing the cancer cell to undergo apoptosis

Question 9

what are the treatments for cancer?

Answer 9

radiotherapy
- kills cancer cells but destroys the surrounding tissue

chemotherapy
- cytotoxic drugs kill cancer cells but healthy cells can be killed in the process as well

surgery
- removes tumour but it can be hard to get all the cancer cells

Question 10

what role does activation immunotherapy play when it comes to how monoclonal antibodies are used in cancer treatments?

Answer 10

• Naked mAbs
  ○ Do not have any other molecules joined to them
  
  • Conjugated mAbs
    ○ Have additional group/s attached
    § Radioisotope
    □ Antibody link to its target antigen on the cancer cell where the radioisotope emit radiation that can destroy the cancer cell
    § Chemotherapy drug
    □ Antibody delivers the cancer-killing drug directly to the target antigen on particular cancer cells

Question 11

what is antibody-dependent cell-mediated cytotoxicity (ADCC)?

Answer 11

a form of activation immunotherapy
- mAbs bind to cancer cells and interact with the cells of the immune system
- Attract Natural Killer (NK) cells, causing them to recognise the antibody-coated cancer cell as foreign and kill it

Question 12

what is complement activation?

Answer 12

a form of activation immunotherapy
- mAbs bind to cancer cells and interact with complement proteins
- Number of different types of proteins found in the blood that opsonise, cause lysis, and attract phagocytes to invading pathogens
* Complement proteins then go on to destroy the cancerous cells (either by forming a membrane attack complex (MAC) OR by enhancing the function of other immune cells)

Question 13

what is checkpoint inhibition?

Answer 13

a form of activation immunotherapy
- when monoclonal antibodies can be used to block immune checkpoints so that the immune system can destroy cancer cells more easily
- Some cancer cells secrete molecules that stimulate immune checkpoints (reduces the immune system’s ability to recognise and destroy them)

Question 14

why are immune checkpoints important for the immune system?

Answer 14

• They act as regulators in the immune system that, when activated, suppress the immune system

Question 15

what are autoimmune diseases?

Answer 15

• When ‘self cells’ aren’t recognised by their immune system and it attacks the persons own cells (EVEN THOUGH THE CELLS HAVE THEIR OWN HLA (MHC markers))
  ○ Symptoms are brough on by the B and T cells responding to self-tissues as if they were foreign
  - B cells release autoantibodies
  - T cells become autoreactive

Question 16

what role does suppression immunotherapy play when it comes to autoimmune diseases?

Answer 16

• Used to reduce the immune system’s ability to attack self-cells ( leads to immunosuppression)

Question 17

what are some of the ways suppression immunotherapy works in autoimmune diseases?

Answer 17

cytokine inhibition
- Cytokines are messenger molecules used by the immune system to coordinate its response. Monoclonal antibodies that bind to and inhibit cytokines can be used to reduce the immune response

B cell and T cell depletion and inhibition
- Monoclonal antibodies that bind to
autoreactive B and T cells can be used to either inhibit these cells or stimulate other
immune cells to destroy them.