Lecture 21 Thrush

Question 1

Alloreactivity

Answer 1

T cells respond to foreign MHC and become activated

Something about t cell receptor recognizes it and T cells become activated.

Question 2

Describe cancer cells and what causes them to be that way

Answer 2

Cancer cells are self cells; altered self cells due to mutations

Question 3

Describe cell cycle of cancer cells

Answer 3

lack apoptosis
mutation in p53
telomerase is active… repairs cancer cells so they don’t die
cancer cells are also malignant (spread to other areas of the body)

Question 4

Describe the chemical, physical, and biological agents associated with causing cancer

Answer 4

Other things can lead to cancer
Chemical: nitrates, nicotine, asbestos
Physical: radiation and UV light
Biological: other viruses such as HPV, EBV, HTL-V

Question 5

role of cmyc

Answer 5

want the cell to divide- c myc turned on

want cell to rest- turned off

Question 6

Burkitt’s lymphoma

Answer 6

B cell tumor

when c- myc is moved to IgH gene enhancer

Question 7

Why is the immune system not always able to destroy cancer cells?

Answer 7

We know that immune system does play some role because those who are immunosuppressed have a greater chance at developing cancer

different things can alter the DNA/ cells/ proteins to make body see them as foreign (Ex: melanoma caused by UV radiation can alter proteins causing body to fight against own proteins)

since some cells are host dervived they may not be recognized as antigen

TILs alo recognize the antigen and come to it but something suppresses the t cell and it is unable to respond

Question 8

Tumor Antigens

Answer 8

used to induce an immune response
can be tumor specific (rare)
tumor associated (more common)

Question 9

Tumor Antigens I

Answer 9

TSTA: unique to tumor cells/ not on normal cells (difficult to find) (HPV)

TATA: not unique; proteins found at different developmental stages; proteins expressed much higher on cancer cells

Question 10

Tumor Antigens II (oncofetal)

Answer 10

CEA: found on colon cancers
AFP:liver and germ cell tissues; increased in hepatitis; after tumor therapy iincrease= relapse

Question 11

Tumor Antigens III

Answer 11

expressed and presented with MHC 1
some viral proteins cause abnormal regulation of cell
Oncogenes: abnormal
Protooncogenes: normal but mutated causing cancer

Question 12

examples of tumor antigens that can be used for detection of tumor growth

Answer 12

HPV- viral- cervical carcinoma- ncoviral

Surface immunoglobin- gene arrangements with B cell- lymphoma- differentiation

Question 13

If tumor antigens, why no immune response?

Answer 13

lack of antigenic epitope
decreased MHC expression
lack of co simulation (n B7)
Production of inhibitory substances 
shedding of tumor antigens

Question 14

CAncer Therapy

Answer 14

Conventional: surgery, radiation, chemotherapy drug treatment

Passive:monoantibody against tumor specific antigens
Ab- to Fas= apotosis
prevent angiogenisis: blocking blood supply to cancer

Active:
TILs : isolate them; inject with IL-2 and give back in pt.
DCs with tumor antigen
Bone Marrow Transplant (lymphoid origin)
cytokines (IL-2; INF alpha)
vaccination

Question 15

CD20

Answer 15

typical marker for B cell cancer