Stem Cells in Medicine

Question 1

Which conditions are due to faulty cells?

Answer 1

• Type 1 diabetes - damage to the pancreas cells which normally would produce insulin.
• Paralysis - sometimes caused by damaged nerve cells
• Sickle cell anaemia - caused by misshapen red blood cells

Question 2

How do stem cells help these conditions?

Answer 2

• Stem cells are cells that work properly which are used to replace they fault/damaged cells

Question 3

How do scientists replace the faulty cells with working stem cells? (Embryonically)

Answer 3

Most common method:
1. - Extract embryonic stem cells from early embryos
2. - Grow them in a laboratory
3. - Stimulate them to differentiate into whichever type of specialised cell that we want
4. - Then give them to the patient to replace their faulty cells.

Question 4

What are the drawbacks of replacing faulty cells with embryonic stem cells?

Answer 4

1. • It requires embryonic stem cells (as these are the only ones that are able to differentiate into any type of cell)
     This means that:
     - There is a limited supply
     - Ethical issues
2. • Rejection - The embryo and the patient have different genomes, the patient’s immune system may reject the stem cells. (Tries to destroy them as the body identifies them as foreign).
     - This can be reduced by giving the patient medication to suppress their immune system.
     (This doesn’t always work and can have side effects).

Question 5

What is an alternative method instead of using embryonic stem cells? (Overcoming the embryonic drawbacks).

Answer 5

• Using adult stem cells:
• They are easy to get ahold of
• Won’t cause rejection as they can be taken from the patient themselves.

Question 6

What is a drawback of using adult stem cells?

Answer 6

• Adult stem cells can only differentiate into different types of blood cells. E.g: Red blood cells, White blood cells, Platelets.
• This means they can only treat blood cell disorders e.g: sickle cell anaemia.

Question 7

What are the risks of using stem cells in medicine?

Answer 7

1. • Virus transmission - If the donor stem cells are infected with a virus (either before taken by the scientist or in the lab) when they are transferred into the patient, they would also transfer that virus which could infect the patient and cause more problems.
2. • Tumor development - Because stem cells divide so quickly, there is a chance they will get out control once they’ve been transplanted into the patient. This could devleop into a tumour/cancer

Question 8

What are the ethical objections using embryonic stem cells?

Answer 8

The human embryos being used have the potential for human life:
- Morally and religiously, people object to their use in research.
- Others think that the benefits of curing existing people who are suffering is more important than the rights of embryos.
*The embryos used are the unwanted ones from fertility clinics, so otherwise would have been destroyed. It is also tightly controlled by the government.