using stem cells in medicine: potential benefits

stem cell in medicine

1. Using stem cells in medicine: potential benefits, risks and ethical issues Stem cells and differentiation

2. How our teaching resources are designed for the classroom

3. Laura Izzy Andeep Jacob Listen to others . It is okay to disagree with each other, but we should listen properly before making assumptions or deciding how to respond. When disagreeing, challenge the statement not the person. Respect privacy. We can discuss examples but do not use names or descriptions that identify anyone, including ourselves. No judgement. We can explore beliefs and misunderstandings about a topic without fear of being judged. Choose level of participation. Everyone has the right to choose not to answer a question or join a discussion. We never put anyone ‘on the spot’.

4. I can describe examples of how embryonic and adult stem cells could be used in medical treatments, including potential benefits, risks and ethical issues.

5. s pecialised cell e mbryonic stem cell e thical a dult stem cell i mmune rejection A cell taken from an embryo that can differentiate into any type of specialised cell. A differentiated cell that is adapted to carry out a particular function. An ethical issue relates to whether an action and its consequences are right or wrong. A cell found in specific regions of the body that can differentiate into a limited number of related specialised cells. W hen a patient’s immune system attacks non-self cells (e.g. transplants).

6. Stem cell uses in medicine Benefits, risks and ethical issues Using stem cells in medicine: potential benefits, risks and ethical issues

7. Stem cell uses in medicine There are two types of human stem cell: E mbryonic stem cells can differentiate into any type of specialised cell . embryonic stem cells cardiac muscle cells red blood cells epithelial cells neurones

8. Stem cell uses in medicine skin bone marrow liver heart blood muscle eyes brain A dult stem cells can differentiate into a limited number of related specialised cells in certain regions of the body. differentiation epithelial tissue smooth muscle fat tissue adult skin stem cell

9. adult stem cells Stem cell uses in medicine Choose the two sources of stem cells for use in medicine. childhood stem cells embryonic stem cells plant stem cells

10. Stem cell uses in medicine In a lab, the stem cells can be stimulated to differentiate into many types of specialised cell that could potentially be used to treat disease, genetic disorders and injuries. 5-day-old embryo specialised cell cell removed e mbryonic stem cell differentiation stimulated Embryonic stem cells can be taken from a 5-day-old embryo, before differentiation has occurred. Embryos can be sourced from IVF clinics where they are no longer required.

11. Type 1 d iabetes is a genetic disorder in which the patient cannot control their blood sugar concentration. Stem cell uses in medicine Beta cells in the pancreas are destroyed, so the hormone insulin is not produced. Scientists are researching a potential treatment. Embryonic stem cells are stimulated to differentiate into beta cells, which could be transplanted into the pancreas. beta cells pancreas differentiation transplantation embryonic stem cells Example: Digestive system: Christos Georghiou/Shutterstock

12. Multiple sclerosis is a condition in which the myelin sheath around the axon of neurones is damaged. T his slows down the nerve impulses that control the body. Stem cell uses in medicine Damage to the brain and spinal cord neurones can lead to permanent changes in body function. Neurones do not divide (by mitosis), so cannot replace themselves. embryonic stem cells neurone in brain neurone in spinal cord Scientists are researching a potential treatment using embryonic s tem cells. differentiation stimulated Example:

13. In the procedure below, which is a specialised cell? Stem cell uses in medicine 5-day-old embryo neurone cell (used to treat spinal cord injury) cell removed embryonic stem cell differentiation stimul ated a b c

14. All blood cells are made from adult stem cells in our bone marrow. Stem cell uses in medicine red blood cells white blood cells bone marrow stem cells Adult stem cells from a donor’s bone marrow can be used as a treatment. Adult stem cells can also potentially be used as treatments. Example: Leukaemia is a type of cancer that results in faulty blood cells being made.

15. Adult stem cells from bone marrow are donated by members of the public in a surgical procedure. Stem cell uses in medicine red blood cells white blood cells These stem cells can be transplanted into a patient with leukaemia to replace their faulty bone marrow stem cells . bone marrow stem cells bone marrow donation Blausen Medical Communications, Inc., CC BY 3.0

16. They are used to replace blood cells damaged by the disease. Stem cell uses in medicine Adult stem cells are used in treatments for leukaemia. They differentiate into a limited number of different cells.

17. Stem cell uses in medicine Adult stem cells can be donated, or a patient’s own stem cells can be harvested. Another source of stem cells for research is therapeutic cloning. This technique takes an egg cell and replaces its nucleus with a nucleus from one of the patient’s body cells. body cell from patient egg cell from donor nucleus removed nucleus transferred to egg cell c ell develops into embryo stem cells are removed The stem cells formed in the embryo are genetically identical to the patient.

18. spinal cord damage measles diabetes Stem cell uses in medicine Choose the conditions that stem cells could be used to treat. malaria

19. Stem cell uses in medicine Stem cells could potentially be used to treat a number of disorders, in addition to the examples we’ve already seen. Carry out research into Parkinson’s disease and write a summary of the use of stem cells in their treatment. Include basic details of the condition, the process and the outcomes achieved .

20. Stem cell uses in medicine Parkinson’s disease causes the destruction of neurones which help to control movement and mood. Embryonic stem cells can be used and differentiated into neurones. The neurones are transplanted into the brain of the patient with Parkinson’s disease. Improvements in symptoms have been proved but research continues. Example: Carry out research into Parkinson’s disease and write a summary of the use of stem cells in their treatment. Include basic details of the condition, the process and the outcomes achieved.

21. Stem cell uses in medicine Benefits, risks and ethical issues Using stem cells in medicine: potential benefits, risks and ethical issues

22. Benefits, risks and ethical issues Potential uses of stem cells are the subject of lots of research; the full extent of their use is still not known. stem cells muscle cells t esting cells with drugs to treat heart disease However, in some cases stem cells have been used to: help patients with currently untreatable conditions grow organs (e.g. skin) for transplants reduce symptoms of progressive diseases. They can also be used in research to study the effect of drugs (i.e. toxicity) on different types of cells.

23. Benefits, risks and ethical issues Adult stem cell transplants are a treatment for leukaemia. stem cells removed from patient and stimulated to divide stem cells genetically identical to patient Using a patient's own stem cells prevents immune rejection as the cells are genetically identical and recognised as ‘self’.

24. Benefits, risks and ethical issues This makes the patient more susceptible to other infections. patient taking medication Immune rejection is where the patient’s immune system attacks non-self cells. Stem cells from a close relative can be used, but the patient has to take medicines called immunosuppressants to prevent immune rejection.

25. replace cells damaged by drug treatments Benefits, risks and ethical issues grow tissues and organs for transplant replace cells damaged by diseases (e.g. Parkinson’s) Select the current uses of stem cells. producing human clones

26. A donor might not be a close relative and could have different types of cells. Benefits, risks and ethical issues It is more effective to use a donor rather than the patient’s own cells for stem cell transplants. A donor is genetically different, so their cells may be rejected by the patient’s immune system.

27. Benefits, risks and ethical issues The use of embryos for stem cells and in therapeutic cloning raises some ethical issues. foetus embryo differentiation and growth An ethical issue relates to whether an action and its consequences are right or wrong. T he embryos used in medical research are those that would be destroyed as medical waste. But they are also the first development stage of a new human being.

28. Benefits, risks and ethical issues Individuals and groups have differing opinions on when life begins. 1 week 2 weeks 3 weeks 4 weeks 8 weeks 12 weeks 16 weeks 24 weeks 40 weeks Using embryos from IVF or making them in therapeutic cloning risks them becoming seen only as a commodity. In the UK, the Human Fertilisation and Embryology Authority (HEFA) oversees the use of gametes and embryos. The owners of the gametes that formed the embryo must consent to its use. Embryos must not be developed further than 14 days in a lab.

29. Benefits, risks and ethical issues There are also some clinical issues that limit the use of stem cell technology: t he success rate for therapies varies between patients access to embryonic stem cells is limited there is difficulty in recruiting stem cell donors stem cells can have a higher rate of mutations that can lead to cancer viruses cause diseases viruses can spread between stem cells in culture.

30. Benefits, risks and ethical issues There are also issues related to society’s understanding and opinion on the use of stem cells. Support for research and the use of stem cells requires education of the public on their benefits and where the current research is. It is not currently clear whether the benefits outweigh the risks and ethical objections. As lots of the research is carried out by clinics for profit, it could mean that patients have their hopes raised or are exploited. benefits risks ethical objections

31. Using an adult’s own stem cells to avoid immune rejection. Benefits, risks and ethical issues Which of these is an ethical issue with using stem cells in medicine? Lack of public understanding of the potential uses. Objections to the use of embryos. Varied success rates of treatments.

32. Benefits, risks and ethical issues Laura and Andeep describe how to write an evaluation of an application of science, such as the use of stem cells. An evaluation must give both pros and cons. An evaluation must state some uses, and describe them with scientific detail. Write an evaluation of the use of stem cells in medicine. Include some of the scientific ideas behind this use, and discuss benefits, risks and possible issues. Laura Andeep

33. Benefits, risks and ethical issues Write an evaluation of the use of stem cells in medicine. Include some of the scientific ideas behind this use, and discuss benefits, risks and possible issues. Stem cells are undifferentiated cells. Embryonic stem cells can differentiate into any specialised cell; adult stem cells can differentiate into a limited number. Stem cells can be stimulated to differentiate into specialised cells that can replace those damaged by treatments (e.g. leukaemia ). The specialised cells can also be used to test drugs for some conditions (e.g. heart disease). Use of embryos raises ethical concerns as an embryo is the first stage in human development. There are also issues to consider such as profit-making from vulnerable patients, and a lack of understanding of the potential use and limits of stem cells in medicine. Stem cells have a higher rate of mutations that can lead to cancer, and viruses can spread between stem cells in culture.

34. Embryonic and adult stem cells can be used in treatments to make new specialised cells to replace damaged ones. They can also be used to test drugs for toxicity. Examples of uses include bone marrow transplants for leukaemia, and potential treatments for type 1 diabetes and multiple sclerosis. Transplanting stem cells into a patient has risks including immune rejection if they are not the patient's own cells, infection with viruses, and cancer due to mutations and uncontrolled cell division. There are ethical objections to using embryos as a source of embryonic stem cells. When evaluating the use of stem cells in medicine, we must consider whether benefits outweigh risks and ethical issues. Using stem cells in medicine: Potential benefits, risks and ethical issues