Definition

Question 1

Tumour cells

Answer 1

These are altered self cells that have escaped normal growth regulating mechanisms

Question 2

Tumor immunology

Answer 2

Part of immunology that deals with antigens on tumor cells and immune response to them

Question 3

Tumor antigen

Answer 3

Antigen that elicits an immune response that have been demonstrated in many experimentally induced tumors and some human cancers

Question 4

Tumor specific antigen

Answer 4

Unique to malignant cells
And does not occur on normal cells
Usually are products of mutated genes seen in cancer cells.
When they are presented on class 1 MHC , they wlicit immune response
Induced by :
chemical carcinogens
Physical carcinogens
Viral carcinogens

Question 5

Tumor associated ag

Answer 5

Are not unique to malignant cells
Present on tumor cells and also on some normal cells at a very low concentration
Expression of these ag is considerably depressed or enhanced after the process of malignant transformation

Question 6

Oncofetal ag

Answer 6

These ag are found not only in tumor cells but also on normal fetal cells
They appear early in embryonic life before the immune system acquires maturity
Eg. CEA
AFP

Question 7

CEA

Answer 7

Detection by RADIO IMMUNO ASSAY
Detection is not helpful in diagnosis but helpful in management of tumor
If CEA Level decline then tumor is not spreading
A rise in CEA level in pts with resected colon Ca suggests recurrence or spreading of tumor

Question 8

AFP

Answer 8

Normally found in
Fetal liver
Some normal sera

Increased in sera of hepatoma pts

Question 9

Mechanism if Tumor immunity

Answer 9

Innate immunity
Acquired immunity

Question 10

Innate immunity

Answer 10

Nk cells kill the cells that display tumor ag

Question 11

Aquired immunity

Answer 11

CMI - DESTRUCTION BT 1.ACTIVATED MQ
2.DESTRUCTION BY CYTOTOXIC T CELLS
3.ADCC BY NK CELLS
HI- 1. LYSIS BY ANTIBODY AND COMPLEMENTS
2. AB MEDIATED LOSS OF TUMOR ADHESION
3. AB AND COMPLEMENT MEDIATED OPSONIZATION