Monoclonal Antibodies

Question 1

What is a monoclonal antibody?

Answer 1

An antibody from a white blood cell is extracted and cloned, theyre produced from a single clone of cells

Question 2

Which WBC’s are used to produce monoclonal antibodies?

Answer 2

Ones that produce antibodies known as B-lymphocytes

Question 3

Why are monoclonal antibodies important?

Answer 3

• if you know the type of antibody that the body needs to fight a pathogen, being able to isolate and do this, you can produce many of them
• they can be injected into a person with the disease

Question 4

How do monoclonal antibodies work?

Answer 4

1) . They’re specific to one antigen and can attach to it, helping the pathogen to be destroyed
2) . Some MA are able to bind to receptor sites on chemical eg toxins by bacteria
3) . They are extracted from the lymphocyte and are copied many times
4) . They can be injected into patient with a needle

Question 5

How are monoclonal antibodies made?

Answer 5

1) . mouse lymphocytes are stimulated to make a particular antibody
2) . they are then combined with a tumour cell in a combination called Hybridoma
3) . Hybridoma can then divide and make the antibody 4). single hybridoma cells are cloned and produce identical antibodies, they are collected and purified
5) . They are then injected

Question 6

Why are B-Lymphocyte and tumour cells used together?

Answer 6

B-lymphocytes dont divide easily (mitosis) and are then hard to obtain
Tumour cells divide easily and can be grown easily in a lab. They dont produce antibodies

Question 7

Why do cancerous cells have different antigens to healthy body cells?

Answer 7

Mutations in their DNA

Question 8

What can monoclonal antibodies do for cancerous cells?

Answer 8

they target specific cells ie the cancer cells as they only bind to the tumour markers, so the drug kills the cancer cells and leaves normal cells alone

Question 9

How do monoclonal antibodies work in cancer?

Answer 9

an anti cancer drug can be attached to these MA, it may be a radioactive substance, a toxic drug or a chemical which stops cancer cells growing or diving

Question 10

What does a pregnant woman produce?

Answer 10

A hormone called HCG in her urine

Question 11

What do pregnancy tests contain?

Answer 11

A monoclonal antibody which binds to the hormone, the antibodies have blue beads attached to it

Question 12

How do pregnancy sticks work?

Answer 12

1) . Woman urinates in the stick with the antibodies in it
2) . Hormone HCG binds to the antibodies with the blue beads
3) . The urine travels up the stick carrying the antibodies and beads
4) . The hormone/bead/antibody bind to more antibodies which are attached to the strip in the pregnancy stick
5) . The blue beads get stuck to the strip, turning it blue

Question 13

What happens if you are not pregnant?

Answer 13

Urine still travels up the stick with the blue beads but there is nothing to stick the blue beads to the test strip so it doesnt turn blue

Question 14

What are the advantages of monoclonal antibodies?

Answer 14

• they leave healthy cells alone
• cancer treatment
• are cheaper to use as you can have a smaller dose
• have fewer side effects than chemotherapy or radiotherapy, as they leave normal cells alone

Question 15

What are the disadvantages of monoclonal antibodies?

Answer 15

• side effects such as fever, vomiting
• have more side effect than initially expected so they are not widely used as treatments as scientists had originally hoped

Question 16

What is a drug?

Answer 16

A chemical that changes the way the body works

Question 17

What happens in stage 1 of laboratory testing?

Answer 17

Drugs are tested on computer stimulation models or human cells/tissue grown in the lab

Question 18

Why do many substances fail stage 1 of laboratory testing?

Answer 18

They damage the cells or do not work

Question 19

What limitations does stage 1 of laboratory testing have?

Answer 19

Cannot show the effect of the drug on an entire organism, as the drugs may have side effects for other organs

Question 20

What happens in stage 2 of laboratory testing?

Answer 20

• The substances are tested in animals

- animals are given a certain amount of the substance and the side effects are monitored

Question 21

What does the law in UK say about testing?

Answer 21

All new drugs must be tested on two mammals before given to people

Question 22

What happens in stage 2 part 2 of laboratory testing?

Answer 22

Tested for three things:-

• efficacy of the drug, does it work
• toxicity of drug, how harmful is it
• does, what concentration should be given

Question 23

What are the pros of animal testing?

Answer 23

• able to see what drugs work for certain illnesses
• safest way to see if the drug is dangerous
• see if there are any side effects

Question 24

What are the cons of animal testing?

Answer 24

• ethical concerns ic welfare of animals
• have to go through multiple trials especially if 1st one fails
• time consuming and expensive
• not that accurate as humans and animals are not going to get identical results

Question 25

What happens in phase 1 of clinical testing?

Answer 25

If they pass stage 2 of lab testing, substances are tested on human volunteers

Question 26

Why do the human volunteers have to be healthy?

Answer 26

• if we tested on a ill person the symptoms of the condition will make drug side effects difficult to see
• if the drug is toxic an unhealthy person may not be able to recover

Question 27

Why are clinical tests done?

Answer 27

To see whether they are safe for humans to use, allows us to find out whether the drug has any harmful side effects on a normally functioning body

Question 28

What happens in clinical testing part 2?

Answer 28

If they’re safe, the drugs are tested on people who have the condition or disease

Question 29

What is the purpose of phase 2 clinical testing?

Answer 29

To find out if the drug actually works and enables the researchers to find the optimum dose

Question 30

What two groups are patients randomly put into?

Answer 30

• patients given the drug

- patients who are given a placebo

Question 31

What is a placebo?

Answer 31

A inactive drug that does not work

Question 32

What is the placebo effect?

Answer 32

When a patient is given the drug, they psychologically begin to feel better as they expect the drug to work
They report fewer symptoms even though the drug isnt working

Question 33

What does having a control and placebo group allow scientists to do?

Answer 33

To see the actual difference that the drug makes

Question 34

What are clinical test blind trails? Who knows the difference?

Answer 34

Volunteers do not know whether they are taking the new drug or a placebo.
Researchers know the difference and this van lead to the give away of clues making the test unfair

Question 35

What is a double blind trial? What does it remove?

Answer 35

Neither the volunteer nor the researcher knows which is the placebo and which isnt.
Removes bias and risk of doctors subconsciously influencing the results

Question 36

What is peer review? And what does it mean?

Answer 36

If a drug passes all of the previous stages it must be peer reviewed, ie other scientists must check that the work is valid and that the tests are carried accurately

Question 37

What happens if the drug passes peer review?

Answer 37

Results can be published in a scientific journal

Question 38

How are monoclonal antibodies used in research?

Answer 38

• bind to hormones and other chemicals in blood to measure levels
• test blood samples
• locate specific molecules in a cell or tissue

Question 39

what are plants physical defences?

Answer 39

• leaves and stems have waxy cuticles which act as barriers
• cell walls
• layers of dead cells around their stems

Question 40

what are plants chemical defences?

Answer 40

• antibacterial chemicals which kill bacteria

- produces poisons which deter herbivores

Question 41

what are plants mechanical defences?

Answer 41

• thorns and hairs
• leaves that droop or curl, when something touches
• some plants mimic other organisms