Immunotherapies

Question 1

What are cancer immunotherapies

Answer 1

cancer treatments that use our own immune system to prevent and eliminate cancer

Question 2

What are the 3 immunotherapy tactics

Answer 2

1. Boost the immune system to wake immune cells to fight the cancer
2. Unmask - flag the cancer cells to allow the immune cells to fight it
3. Engineer immune cells’ DNA to program them to detect and fight cancer

Question 3

How do immune checkpoint inhibitors work

Answer 3

They block the immune checkpoints to allow the immune system cells to kill the cancer cells

Question 4

What are the different immunotherapy types?

Answer 4

1. monoclonal antibodies
2. Adoptive cell transfer
3. Vaccines
4. Immune checkpoint inhibitors
5. man-made cytokines

Question 5

How does Sipuleucel-T (Provenge) work

Answer 5

It is a cancer vaccine for prostate cancer

The patient’s blood is taken and the dendritic cells are isolated
They are activated by granulocyte-macrophage stimulating factors and prostatic acid phosphatase (which is a specific antigen to prostate cancer)
These activated dendritic cells present the PAP antigen on the MHC complex
T cells recognise this as cancer and become activated
T cells recognise PAP peptides on the surface of cancer cells and attack

Question 6

What do man-made cytokines do, and what is a downfall of this treatment

Answer 6

they boost the immune system activity

cytokine storm - overactivation of the immune system

Question 7

How does CAR T-cell therapy work

Answer 7

1. patients blood is taken
2. gene that encodes for cancer specific antigen is incorporated into patients T cells dna
3. CAR T-cell receptors are produced on the surface of T cells
4. Patients is given chemo/radiation therapy to get rid of non-engineered T cells
5. CAR T cells are grown in the lab then are infused into patient
6. CAR T cells recognise antigens on the cancer cells
7. CAR T cells activate, proliferate and become cytotoxic

Question 8

What are 3 side effects of CAR T cell therapy

Answer 8

1. cytokine release storm
2. CD19 CAR T cell therapy kills normal B cells as well as cancerous B cells = higher chance of infection
3. neurological toxicity - aphasia - loss of ability to speak coherently

Question 9

What are CTLA-4 and PD-1

Answer 9

immune checkpoints

Question 10

What type of immune checkpoint inhibitors are anti-CTLA-4 mAbs

Answer 10

inhibitory

Question 11

How does CTLA-4 act as an immune checkpoint

Answer 11

It has a stronger affinity for B7.1/2 compared to CD28. When CTLA-4 on the cytotoxic t cell and B7.1/2 on the antigen presenting cell bind it causes the t cell to remain inactive

Question 12

How does anti-CTLA-4 mAbs work

Answer 12

It blocks the B7.1/2-CTLA-4 binding and allows the CD28 to bind with B7.1/2 which allows t cell activation

Question 13

What is an example of a anti-CTLA-4 mAb

Answer 13

Ipilimumab

Question 14

How does CTLA-4 act as an immune checkpoint

Answer 14

It has greater affinity for B7.1/2 compared to CD28, when this binds it keeps the T cell inactive

Question 15

How does PD-1 and PD-L1 act as an immune checkpoint

Answer 15

PD-1 is located on T/B cells
PD-L1 is located on cancer cells

PD-1 binds to PD-L1 which keeps the t cell inactive

Question 16

How does anti PD-1 mAbs work

Answer 16

they allow the T cell to become activated by inhibiting PD-1

Question 17

What are two examples of a anti PD-1 mAb

Answer 17

Nivolumab
Pembrolizumab

Question 18

How does anti PD-L1 mAbs work

Answer 18

allow the T cell to become activated by inhibiting PD-L1

Question 19

What is an example of a anti PD-L1 mAb

Answer 19

atezolizumab