The capacity for long term self renewal in stem cells marks the importance of this area in treating patients. Stem cells can replace damaged cells in the body after injuries. These properties have led to the investigation of the potential uses of stem cells in supplying cells to treat diseases such as Parkinson's disease , heart disease, diabetes and other degenerative diseases. With these diseases, cells have been irreversibly lost and cannot be self regenerated. There are only treatments, but no cures for these diseases. Therefore, directing the stem cells to become the appropriate specialized cells followed by transplantation is the hope of these patients with damaged tissues. The stem cells can be generated to various cell types.
The therapeutic usages of adult stem cells have been established, including bone marrow transplants and skin grafting. A bone marrow transplant requires the removal of bone marrow from the donor and transplantation to the patient with a blood disease (leukaemia or an anaemia), to generate new blood cells. This technique is called regenerative medicine or cell therapy, which is similar to organ transplantation but works with cells only. However, the use of embryonic stem cells has just been approved in the United States in 2009. Scientists believe that there is still a long way to go before stem cell therapy can replace or replenish damaged cells and tissues in actual human patients.
Neurological diseases are disorders of the central and peripheral nervous system, including the brain, spinal cord and the peripheral nerves, which share common characteristics of neural dysfunction, progressive deterioration and loss of neural cells. However, they have diverged pathological and genetic mechanisms.Therefore, stem cell replacement therapy should be disease specific to provide optimal treatment to the patients.
Both embryonic and adult stem cells are transplanting approaches for neurological diseases, for example haematopoietic and bone marrow derived stem cells, neural stem cells, and mesenchymal stem cells. The therapy for Alzheimer's disease is to repopulate the degenerated brain. Currently, stem cell treatment is undergoing preclinical studies using animal models, with some promising results in transplanting stem cells with molecules of neurological function together. There is an improvement in a mouse's cognitive functions and the disease's pathogenesis hallmarks. However, scientists have suggested an addition of other factors is needed to support the therapy. A recent work reported on the generation of neuronal cells in a mouse brain by using neural and mesenchymal stem cell transplantation together with a small compound, with the improvement of cognitive function of the animal model. With the current technology, there is still a long way to go to ensure the safety and efficacy of stem cell therapy in human beings.
Potential areas of stem cell research in disease management
The following are some areas that could benefit from more research into how stem cells could be used to manage disease.
- Production of specific cell types in the laboratory for drug testing or drug screening
Drug testing for newly developed drugs on cell lines is common in pharmaceutical research. Large amounts of cells with the same characteristics or properties can be used to test the medicines developed. Therefore, the amount of testing done on animals can be reduced considerably.
- Study of disease processes with the aid of stem cells
To obtain the damaged cells in a disease for studying the process is very difficult, especially the cells with poor regeneration after injuries or degenerative diseases, such as nerves and the pancreas. Scientists could engineer the damaged cells to carry the disease gene from stem cells. This model can help our understanding of disease processes.
This section has covered some current and potential areas of stem cell research in biological and medical sciences. Can you think of any other potential areas? You are encouraged to think about other possible applications and to look for more information about current developments in stem cell research.
Apart from the advancement of technology, ethical issues are also a major concern when conducting research on animals or, more importantly, on human beings. It is important for you to know that striking the balance between research and ethics is crucial in research design and methods. The next section will introduce some of the different angles on embryonic research taken by members of society and the scientific field.
- In what ways can stem cells help to treat patients?
- How can stem cells be used?
- Based on the two types of stem cells discussed so far, what are their advantages and disadvantages in treating diseases?
- What are the focuses of stem cell research that scientists are investigating today?
- When and how embryonic stem cells make decisions to produce more specialized cells.
- How stem cells work in adults.
- How stem cells help to treat diseases.
- All of the above.
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- With degenerative diseases such as Parkinson's disease (brain cells), heart disease (heart muscles), and diabetes (pancreatic cells), cells have been irreversibly lost and cannot be self regenerated. The capability of long term self renewal in stem cells mark the importance of this area in treating patients.
- Adult stem cells: bone marrow transplants and skin grafting. Embryonic stem cells: repopulating the degenerated cells and transplanting stem cells to the patients.
- Adult stem cells: Advantages: long history, treating blood cell cancer through transplantation. Disadvantages: less proliferative, requires high compatibility between donor and recipients, invasive collection procedures. Embryonic stem cells: Advantages: plastic and versatile, pluripotent. Disadvantages: control of development has not been determined, ethical concerns about the use of embryos.
- The research helps us understand the control and process in transition from stem cells to specialized cells (A), how stem cells work (B) and how stem cells can be used in medicine and disease management (C). Therefore, the answer is (D), all of the above.