Stem cells can divide and differentiate, so they can be used to replace cells that are damaged or missing. You need to be able to evaluate the use of stem cells in treating human disorders.Current treatment: bone marrow transplants
Bone marrow contains multipotent stem cells that produce blood cells. A transplant can treat diseases of the blood and immune system, such as leukaemia, sickle cell anaemia and severe combined immunodeficiency (SCID). The patient's own bone marrow is destroyed, then stem cells from a matching donor are put into the blood. They settle in the bone marrow and produce healthy blood cells.Possible future treatments use pluripotent stem cells (embryonic or iPS cells) grown into specific cells, for example:
• new insulin-producing beta cells for people with type 1 diabetes
• nerve tissue to repair spinal cord injuries or to treat Parkinson's disease
• heart muscle to repair damage after a heart attack
• tissues or organs for transplants.Evaluating stem cell therapy
Benefits: it can save lives, improve quality of life, and reduce the need for lifelong drugs or long waits for donor organs.
Problems: donor cells may be rejected by the immune system unless well matched, so patients may need immunosuppressant drugs; stem cells can divide uncontrollably and form tumours; and using embryonic stem cells raises ethical issues, because obtaining them destroys an embryo. Using iPS cells made from the patient's own body avoids the ethical problem and reduces the risk of rejection.
Bone marrow contains multipotent stem cells that produce blood cells. A transplant can treat diseases of the blood and immune system, such as leukaemia, sickle cell anaemia and severe combined immunodeficiency (SCID). The patient's own bone marrow is destroyed, then stem cells from a matching donor are put into the blood. They settle in the bone marrow and produce healthy blood cells.Possible future treatments use pluripotent stem cells (embryonic or iPS cells) grown into specific cells, for example:
• new insulin-producing beta cells for people with type 1 diabetes
• nerve tissue to repair spinal cord injuries or to treat Parkinson's disease
• heart muscle to repair damage after a heart attack
• tissues or organs for transplants.Evaluating stem cell therapy
Benefits: it can save lives, improve quality of life, and reduce the need for lifelong drugs or long waits for donor organs.
Problems: donor cells may be rejected by the immune system unless well matched, so patients may need immunosuppressant drugs; stem cells can divide uncontrollably and form tumours; and using embryonic stem cells raises ethical issues, because obtaining them destroys an embryo. Using iPS cells made from the patient's own body avoids the ethical problem and reduces the risk of rejection.