Lecture 21 11/7/23

Question 1

What are the characteristics of tumor neoantigens?

Answer 1

-encoded by mutations in self antigens
-produce mutated peptides

Question 2

What are the characteristics of cold tumors?

Answer 2

-no CD8+ T cells or NK cells in tumor
-immunosuppressive cells in tumor
-poor prognosis/response to immunotherapy

Question 3

What are the characteristics of hot tumors?

Answer 3

-CD8+ T cells and NK cells present in tumor
-no immunosuppressive cell types
-improved prognosis/killing of tumor cells with immunotherapy

Question 4

What are the two types of antigen-dependent tumor cell killing mechanisms?

Answer 4

-tumor displaying novel antigen on MHCI, triggering cytotoxic T cells
-tumor down-regulating MHCI, triggering NK cells

Question 5

Which receptor is used by NK cells when sensing antibody-coated tumors?

Answer 5

Fc receptor

Question 6

How do tumors escape the immune system?

Answer 6

-induction of Tregs to suppress anti-tumor T cells
-down-regulation of MHCI
-checkpoint blockade
-blocking antibodies

Question 7

What are the two potential types of checkpoint blockade?

Answer 7

-upreg. of CTLA-4 on tumor-specific T cells and expression of CTLA-4L on tumor cells
-upreg. of PD-1 on tumor-specific T cells and expression of PD-L1 on tumor cells

Question 8

How do blocking antibodies work?

Answer 8

mask tumor antigens on cell surfaces and protect them from cytotoxic T cells

Question 9

What are the characteristics of adoptive T cell therapy/CAR-T cells?

Answer 9

-T cells isolated from blood of cancer patient and activated in vitro
-cells infused back into same patient
-modified cells are now specific for tumor antigens and target tumor cells

Question 10

What are the advantages of adoptive NK cell therapy?

Answer 10

-reduced risk of cytokine release syndrome, which is common with CAR-T
-can be produced from healthy donors and be available for immediate use

Question 11

What are oncolytic viruses?

Answer 11

modified viruses used to target and kill cancer cells

Question 12

What nonspecific immune stimulation can aid in fighting tumors?

Answer 12

microbial products
-cytokines

Question 13

What are checkpoint inhibitors?

Answer 13

blocking anti-CTLA-4 or anti-PD-1 antibodies

Question 14

Which vaccines exist to prevent cancer?

Answer 14

-FeLV vaccine
-Marek’s Disease virus vaccine

Question 15

What is the use of CRISPR?

Answer 15

used to edit genes in viruses, bacteria, and host cells