| This article discusses the following | | | | type of cell, adult stem cells can only |
| topics in question format on stem cells: | | | | reproduce cells of their type. If they |
| What are stem cells? | | | | are muscle cells, they can be used to |
| How are stem cells obtained? | | | | reproduce only muscle cells. However, |
| What other potential stem cell sources | | | | recent work has indicated that some |
| are there? | | | | adult stem cells may be able to |
| Why are we and special groups interested | | | | differentiate into other cell types. |
| in stem cells? | | | | Why are we and special groups interested |
| What are the goals of stem cell | | | | in stem cells? |
| research? | | | | Because stem cells can differentiate, |
| How will stem cells affect our future? | | | | that is, can be used to reproduce other |
| If you are deeply interested in stem | | | | cell types, they have tremendous |
| cells for the first time and want to go | | | | potential for solving many human health |
| beyond this article, go to the National | | | | problems. |
| Institute site and read their very | | | | Some groups do not want scientist to |
| comprehensive list of frequently | | | | take human embryos for research in any |
| answered questions (FAQs). The URL is | | | | way whatsoever. Because of this, |
| If you are deeply interested in stem | | | | President Bush restricted stem cell |
| cell research, go to: | | | | research to existing stem cell sources. |
| What are stem cells? | | | | Other governments have stayed out of the |
| The question should be phrased in terms | | | | research arena and stem cells are |
| of embryonic stem cells because that is | | | | collected at the whims of the scientist. |
| what we are talking about here. | | | | Scientists argue that excess stem cells |
| A human embryo is obtained when a | | | | are produced in fertility clinics and |
| woman's egg is fertilized by a man's | | | | that they should be used to benefit |
| sperm. This occurs in the human body but | | | | mankind. |
| it can also be done in a laboratory. The | | | | So, what do you think? |
| procedure is often used in cases of | | | | What are the goals of stem cell |
| infertility. | | | | research? |
| I have three grandchildren formed in | | | | First, scientists want to understand |
| this way. Their mother donated eggs, | | | | differentiation. We all know that the |
| their father donated sperm, and the | | | | human embryo creates all the cell types |
| technicians watched the fertilization | | | | in the human body. Scientists want to |
| take place under a microscope. The | | | | know how and when genes turn on and off |
| fertilized eggs were placed in the | | | | to create a particular cell type. |
| mother and she gave birth to triplets. | | | | Abnormal cell divisions cause birth |
| If embryos formed in this way are not | | | | defects and cancer. Scientists want to |
| placed in the mother they can be and are | | | | know what signals a change in the |
| used for medical research. Often extra | | | | process of cell development. This could |
| fertilized eggs are produced during this | | | | lead to cures for cancer and birth |
| process. Scientist would like to harvest | | | | defects. |
| these extra eggs rather than discard | | | | Stem cells could be used to test new |
| them. They could then use them to obtain | | | | drugs rather than human guinea pigs and |
| stem cells. | | | | animals. Damage to the stem cells would |
| Stem cells are never obtained from | | | | eliminate the drug before it could do |
| fertilized eggs that reside in a woman's | | | | damage in the market place, as so many |
| body. | | | | drugs do now. |
| The embryos obtained after they are a | | | | I would like to quote directly at this |
| few days old are in the form of a mass | | | | point: Perhaps the most important |
| of cells called a blastocyst; the embryo | | | | potential application of human stem |
| of about 150 cells. The blastocyst | | | | cells is the generation of cells and |
| consists of a sphere made up of an outer | | | | tissues that could be used for |
| layer of cells (the trophectoderm), a | | | | Cell-based therapies-treatment in which |
| fluid-filled cavity (the blastocoel), | | | | stem cells are induced to differentiate |
| and a cluster of cells on the interior | | | | into the specific cell type required to |
| (the inner cell mass). | | | | repair damaged or depleted adult cell |
| How are stem cells obtained? | | | | populations or tissues. |
| Cell cultures are grown in the | | | | Today, donated organs and tissues are |
| laboratory by transferring the inner | | | | often used to replace ailing or |
| cell mass of about 30 cells into a | | | | destroyed tissue, but the need for |
| culture dish which has a nutrient broth. | | | | transplantable tissues and organs far |
| The cells quickly multiply and fill the | | | | outweighs the available supply. Stem |
| dish. They are then transferred to other | | | | cells, directed to differentiate into |
| culture dishes and the process goes on | | | | specific cell types, offer the |
| for months. | | | | possibility of a renewable source of |
| Once the cells are obtained they can be | | | | replacement cells and tissues to treat |
| frozen and shipped to other | | | | diseases including Parkinson's and |
| laboratories. | | | | Alzheimer's diseases, spinal cord |
| What other potential stem cell sources | | | | injury, stroke, burns, heart disease, |
| are there? | | | | diabetes, osteoarthritis, and rheumatoid |
| Adult stem cells are a potential source. | | | | arthritis. |
| They can be used to reproduce cell of | | | | How will stem cells affect our future? |
| their type. That is, while embryonic | | | | Have you heard of the Fountain of |
| stem cells can differentiate into any | | | | Youth? |