Cancer and the Immune System

Question 1

What is oncogenesis and what factors contribute to it (4)?

Answer 1

The development of cancer

1. Genetic Mutation
2. Loss of cellular regulation
3. Increased proliferation
4. Reduced immune surveillance

Question 2

What are tissue specific antigens?

Answer 2

Normal proteins found in both normal and cancer cells

Question 3

What are viral antigens?

Answer 3

Foreign products expressed on virally infected cancer cells

Question 4

What are reactivated gene products?

Answer 4

Proteins that normalll are not expressed after fetal development that get “turned on” by the cancer

Question 5

What are mutated gene products?

Answer 5

abnormal proteins

Question 6

Which cells are important in immune surveillance?

Answer 6

CTL cells (CD8 T cells), NK cells, and macrophages

Question 7

What do CD8 T cells do in immune surveillance?

Answer 7

recognize abnormal cels through abnormal internal peptides from cancer cells presented in context of MHC I

Question 8

What do NK cells do in immune surveillance?

Answer 8

1. recognize the down regulation (absence of MHC I)
2. recognize MHC related proteins that are expressed on “stressed” cells which can include cancer cells
3. can bind the Fc portion of the antibody and target cancer cells

Question 9

What do macrophages do in immune surveillance?

Answer 9

phagocytosis of dead/dying cancer cells and presentation of cancer antigens to CD4 T cells

Question 10

What is KIR and what does it do?

Answer 10

KIR- killer inhibitory receptor

Function- binds to MHC I and “protects” cell from NK detection

Question 11

What are the mainstays of anti-cancer therapeutics?

Answer 11

Chemo and radiotherapy

Question 12

What are other immunotherapies that have been tried other than chemo and radiation?

Answer 12

1. Non-specific stimulation
2. Passive immunization
3. Active immunization
4. Expand immune cell population

Question 13

What methods are used with active immunization?

Answer 13

1. Chemically modified tumor cells
2. DNA vaccination
3. Vaccination against oncogenic viruses (Marek’s, FelV)

Question 14

How do you expand an immune cell population?

Answer 14

Remove lymphocytes from patient
grow cells on plate for proliferation
take grown cells and place back into patient

Question 15

What is expressed in nearly all melanomas?

Answer 15

Tyrosinase

Question 16

How is immunotherapy used in B-lineage non-Hodgkin lymphoma? (what does the future hold for immunotherapy question)

Answer 16

1. Isolate T cells from blood and expand these in culture
2. standard chemo
3. administer autologous T cells after chemo
4. Increased tumor free survival by 9 months

Question 17

What types of cells in the immune system can become neoplastic?

Answer 17

Any cell of the immune system

Question 18

Lymphoma is the _____ common hemolymphatic malignancy of dogs and cats

Answer 18

Most

Question 19

Lymphoma can arise from ____ lymphoid cell and usually arises from _________

Answer 19

any lymphoid cell

organized lymphoid tissue

Question 20

What are two clinical features of plasma cell neoplasia?

Answer 20

1. plasmacytoma (solid mass)

2. Myeloma (infiltration in bone marrow or extramedullary sites)

Question 21

How is flow cytometry used?

Answer 21

cells are labeled with antibodies to identify their phenotype

Many of the markers are key cell receptors for differentiation or signaling

Question 22

What types of neoplasia are identified best with flow cytometry?

Answer 22

lymphoid neoplasia

Question 23

What is PARR and how is it used?

Answer 23

PARR- PCR for antigen rearrangement