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Flashcards in ANTIBODIES Deck (38)
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1

What are antibodies

proteins with specific binding sites

2

What are antibodies synthesised by

B cells

3

What are antibodies and what does this allow

proteins, allows a huge variety

4

What structure does the antibody protein have

quaternary

5

What are antibodies made up of

4 polypeptide chains

6

What are heavy chains

long pair of polypeptide chain

7

What are light chains

short pair of polypeptide chain

8

What is formed when an antigen binds to the antibody

antigen-antibody complex

9

What is the binding site on the antibody called

variable region

10

What does the binding site of the antibody consist of

sequence of amino acids

11

What is the rest of the antibody (other than binding site) called

constant region

12

What does the constant region bind to

receptors on cells (e.g B-cells)

13

How do antibodies lead to the destruction of the antigen (when the antigen is a bacteria cell) (2 points)

1) cause agglutination of the bacteria cell
2) then serve as markers that stimulate phagocytes to engulf the bacterial cells

14

How does agglutination of bacteria cell help lead to the destruction of the antigen

makes it easier for the phagocyte to locate them (less spread out)

15

What are the medical uses of monoclonoal antibodies

1) targeting medication to specific cell types by attaching a therapeutic drug to an antibody
2) medical diagnosis
3) pregnancy testing

16

What is an example of an illness that targeting medication to specific cell types by attaching a therapeutic drug to an antibody

cancer

17

What is the most successful targeting medication to specific cell types by attaching a therapeutic drug to an antibody for cancer so far

monoclonal antibody theraphy

18

What is monoclonal antibody therapy (3 points)

1) monoclonal antibodies are produced that are specific to antigens on cancer cells
2) they are given to a patient and attach to the receptors on the cancer cells
3) block the chemical signals that stimulate the uncontrolled growth

19

What is an example of the monoclonal antibody that the monoclonal antibody therapy uses

herceptin

20

What cancer type is herceptin used to try and treat

breast cancer

21

What is an advantage of monoclonal antibody therapy

the antibodies are highly specific and not toxic so have fewer side effects

22

What is another method as an alternative to monoclonal antibody therapy

indirect monoclonal antibody therapy

23

What is indirect monoclonal antibody therapy

involves attaching a radioactive or ctyotoxic drug to the monoclonal antibody, which kills the cells when it attaches

24

What is a cytotoxic drug

drug that kills cells

25

What is an advantage of indirect monoclonal antibody therapy

requires smaller doses, which is cheaper and reduces side effects

26

What are examples of diseases monoclonal antibodies are used to diagnose (4 points)

influenza, hepatitis, chlamydia, cancers

27

What do men with prosyaye cancer produce more of

protein called prostate specific antigen (PSA)

28

How are monoclonal antibodies used to detect prostate cancer

monoclonal antibody that interacts with PSA to measure the level of PSA in the blood

29

How are monoclonal antibodies in pregnancy testing

monoclonal antibodies present on test strips bind to the human chorionic gonadatrophin (hCG) produced by the placenta and found in the mothers urine which moves along the test strip until it is trapped by a different type of antibody to create a coloured line

30

What are the ethical issues of monoclonal antibodies (3 points)

1) production involves deliberately inducing cancer in mice - animal cruelty
2) has saved lives but have caused deaths, need informed consent
3) testing for the safety of the drugs prevents risks

31

What is a real life example of an ethical issue through testing the drugs and what is the possible cause

march 2006, 6 volunteers tested monocloncal antibody , suffered organ failure within minutes - all survived (probably due to T-cells overproducing chemicals that stimnulate an immune response/ attacking the body issues

32

What was the previous issue with producing monoclonal antibodies (2 points)

B-cells:
1) only divide in a living organism
2) are shorted lived

33

Who produced the solution to the issue with B-cells and producing monoclonal antibodies

Milstein and Kohler

34

What procedure did Milstein and Kohler produce (6 steps)

1) mouse is exposed to the non-self material that an antibody is required against
2) B-cells in the mouse produce a mixture of antibodies that are extracted from the spleen of the mouse
3) enable the B-cells to divide outside the body they are mixed with cells that divide readily outside body (e.g. cancer cells)
4) detergent is added to break down the cell-surface membrane of both types of cell & enable them to fuse together to form hybridoma cells
5) hybridoma cells are seperates under a microscope and each cell cultured to form a clone (each clone is tested to see if it is producing the right antibody)
6) any clone producing right antibody is grown on large scale & antibodies extracted from growth medium

35

What are hybridoma cells

cells fused together

36

Why are they called monoclonal antibodies

the antibodies come from a clone formed from a single B-cell

37

What has to happen to the mouse cells before they can be placed in humans

humanisation

38

What is humanisation

modifying the monoclonal antibodies from mouse tissue so that they are like human cells