Stem cell transplants
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Transplanting stem cells, or transplants of specialised cells grown from stem cells, could help people with: • injuries, e.g. spinal injuries leading to paralysis • conditions in which certain body cells degenerate, e.g. Alzheimer’s disease, diabetes and multiple sclerosis • cancers, or following treatments for cancer such as chemotherapy or radiation, e.g. people with leukaemia. Stem cell transplants also enable chemotherapy patients, who have had their bone marrow destroyed, to produce red blood cells. The hope is that we will be able to culture stem cells in limitless numbers. Stem cell lines produced from patients with rare and complex diseases could transform the health service. 3
Name two conditions that could be treated with stem cell transplants.
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Why are stem cell transplants important for people who have had chemotherapy?
Stem cell research and therapy is controversial Stem cell research is necessary to find out more about stem cell development, and the best types to use in treatments. The use of embryonic stem cells, which are removed from a living human embryo, is especially controversial. Until recently, the embryos providing the stem cells were usually those left over from fertility treatments involving in-vitro fertilisation (IVF). Spare embryos would be destroyed if they had not been donated by the IVF couples for research. British law now allows embryos to be created purely for scientific research. Some people object to this. Some religious beliefs argue that new life begins at the point of conception, so an embryo has rights. And who should decide when a human life ends? These are moral and ethical questions. A moral question looks at whether something is right or wrong. An ethical question discusses the reasons why something might be right or wrong. 5
Why do some people object to stem cell transplants?
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Write down one ethical objection to stem cell research.
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What are the potential benefits and drawbacks of using stem cells in medicine?
Figure 1.34 Embryonic stem cells
Did you know? Stem cell transplants are not new. Transplants of bone marrow, which contain stem cells, have been carried out since 1968. But there are very few stem cells in bone marrow (only 1 in 10 000 bone marrow cells). We currently isolate these from blood, rather than bone marrow.
KEY INFORMATION Current potential for adult stem cell use in therapies is restricted to certain cell lines, but it may be greater than once thought. Scientists are trying to induce them to differentiate into a wider range of tissues, a process called transdifferentiation.
Google search: 'adult stem cells, bone marrow stem cells, embryonic stem cells, umbilical cord blood cells'
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