Immunology

Question 1

What is the role of tumor associated antigens?

Answer 1

to distinguish neoplastic cells from normal cells

Question 2

what are the three stages of the immune response to a tumor?

Answer 2

1. Elimination -> abnormal cells are destroyed
2. Equilibrium -> cells resistant to immune response = cells destroyed
3. Escape -> cells resistant > cells destroyed

Question 3

What are tumor mechanisms of evasion?

Answer 3

decreased expression of tumor antigens
decreased expression of MHC proteins
decreased co-stimulatory signals

Question 4

What are the 5 cell types that are involved with neoplasia of the immune system?

Answer 4

1. lymphocytes
2. plasma cells
3. macrophage/APC
4. myeloblast
5. mast cells

Question 5

what characterizes a canine cutaneous histiocytoma?

Answer 5

tumor derived from dendritic cells that can be found on head, ears, muzzle, and legs
tumor infiltrating Tc cells -> may spontaneously regress

Question 6

How can inflammation lead to neoplastic changes? What is an example of this

Answer 6

inflammatory mediators can damage DNA and inhibit apoptosis -> effects of tumor associated macrophages and regulatory T cells

example: vax induced sarcoma, IBD in dogs and cats

Question 7

What is the function of tumor-associated macrophages?

Answer 7

infiltrate tumors and secrete factors that can promote tumor tumor growth and metastasis

Question 8

What is the function of regulatory T cells?

Answer 8

inhibit natural killer cells and Tc cells

Question 9

What is paraneoplastic syndrome?

Answer 9

remote or systemic changes associated with a neoplasm -> may be first indication of cancer

hypercalcemia, hypoglycemia, anemia, cachexia

Question 10

what is the most common cause of hypercalcemia in companion animals?

Answer 10

cancer
anal sac apocrine gland adenocarcinoma
t-cell lymphoma

Question 11

what tumor types can lead to paraneoplastic hypoglycemia?

Answer 11

insulinoma, hepatocellular carcinoma, hemangiosarcoma, melanoma, lymphoma, multiple myeloma

neoplastic cells utilize glucose, gluconeogenesis and glycogenolysis is decreased

Question 12

what can lead to the development of paraneoplastic anemia?

Answer 12

anemia of chronic disease
IMHA (tumor cross rxn)
blood loss anemia
bone marrow disease

Question 13

What is cancer cachexia? What is an important component of development?

Answer 13

Cachexia is progressive wasting with loss of skeletal muscle and adipose tissue seen in 50% of cancer patients

Inflammatory cytokines are important -> TNF alpha, IL-1, IL-6

Question 14

What are the 4 types of cancer treatments available?

Answer 14

1. surgical removal
2. chemotherapy
3. radiation therapy
4. immunotherapy

Question 15

What are 2 methods of tumor non-specific immunotherapy?

Answer 15

macrophage and monocyte activators

NK cell targeted therapy

Question 16

How can the tumor microenvironment be manipulated?

Answer 16

microenvironment: fibroblasts, endothelial cells, macrophages

1. deplete tumor associated macrophages
2. inhibit macrophage migration into tumors

Question 17

What are checkpoint molecule inhibitors? How can they be manipulated to help in cancer treatment?

Answer 17

checkpoint molecules are cell surface molecules that limit T cell proliferation -> CMI’s block these, so more T cells can be produced

blocked with monoclonal antibodies