Cancer Immunotherapy

Question 1

Tumor immunotherapy using passive immunity

Answer 1

administering tumor specific antibody and/or T cells

(passive bc the work is being done for it)

Question 2

Cancer therapy w/antibodies

Answer 2

MAb to block inhibitory signal through CTLA4 or PD1 on T cells (“check-point blockade”) → opsonization, phagocytosis, compliment activation

Question 3

Problem to MAb cancer therapy? solution?

Answer 3

• mutations of tumor Ag
• Ab cocktails

Question 4

Specific ab used for B cell lymphoma?

Answer 4

CD20

Question 5

Current experimental MAb therapy for cancer?

Answer 5

mAbs as immunotoxins

Question 6

Non-specific stimulation of the immune system to fight off tumor (i.e. using adjuvants like BCG to stim MF & Tcells) can lead to which risk factor?

Answer 6

auto-immunity

Question 7

What is cellular therapy (CA immunotherapy)

Answer 7

take DC or T cells, load them w/Ag or activate them → inject them back into the patient

Question 8

CAR-T therapy

Answer 8

chimeric T cell receptor

(first FDA-approved human gene therapy tx)

Question 9

Chimeric T Cell Receptors (CAR-T) have an antigen binding site to bind Ag on tumor cells & has which cell signaling intracellularly?

Answer 9

1. zetta chain → T-cell receptor stim
2. CD137 → better CD8 response
3. CD28 → co-stimulation

(this is personalized medicine; FDA approved)

Question 10

CRISPR/Cas9 technology

Answer 10

knock out PDCD1 gene → T cells are impervious to PD1/ignore it

(instead of using mAb)

Question 11

How is vaccination used to treat cancer?

Answer 11

active treatment (not just preventive) turn on tumor-specific T cells

(administered w/adjuvant)

Question 12

How are cytokines and costimulators used as therapy for cancer (2)?

Answer 12

1. vaccinate w/tumor cells transfected w/B7 molecules → protective immunity
2. transfect w/cytokine genes

Question 13

Which cytokine genes are used to augment immunity in cancer therapy (3)?

Answer 13

1. IL-2 & IL-12 → stim NK & CTL activity
2. GM-CSF → rejection or regression of tumor growth
3. IFN-g → increases cytolytic NK cell activity & expression of MHC I on tumor cells

Question 14

How are heat shock proteins used with tumor-specific peptides as immunotherapy?

Answer 14

DC isolated from pt → loaded w/heat shock protein (from tumor) → return to pt circulation → DCs migrate home to secondary lymphoid tissue → tumor-specific immune response via MHC II presentation

Question 15

What does this flow cytometry result suggest?

Answer 15

Little CD19 → lymphoma

(CD3+, CD4+, CD8+ cells should not be in the periphery & don’t typically carry out immune fxns)