Stem cell research applications and advances

Stem Cell Research

Imagine that it is the end of the twenty-first century: we are living in a world where doctors can create new human organs to order, re-grow crippled spines and damaged hearts, and reverse the damage caused by Parkinson's disease and diabetes without much trouble. Are we imagining an impossible science-fiction scenario or a realistic scientific probability? If the promise shown by the exciting field of stem cell research is anything to go by, all of above and more, may well become a reality much before the end of this century. This essay explores the topic of stem cell research by looking at what stem cells really are; the types of stem cells, their possible benefits and the ethical debate surrounding the issue. It also discusses why stem cell research is important to our society and the future of science.

Background

What are Stem Cells? Stem cells are unspecialized or undifferentiated cells that have the ability to renew themselves through cell division and have the potential to develop into other types of cells such as blood, brain, or heart cells. Although stem cells derived from different sources share these characteristics in general, they also exhibit some differences. There are two basic types of stem cells -- the embryonic stem cells and the adult stem cells.

Embryonic Stem Cells. Embryonic stem cells can be derived from the embryos of mammals during the very early stages of their development. Human embryonic stem cells are isolated from the inner cell mass of embryos that are 5~6 days old. At this stage, the embryo is just a hollow ball of cells about the size of a pinhead and is called a blastocyst ("About Stem Cells"). Such stem cells have the ability to replicate (divide into identical cells) while retaining their potential to develop into virtually any of the 220 cell types that make up the human body. Adult Stem Cells: The 'adult' stem cells are undifferentiated (unspecialized) cells found in certain types of specialized tissue such as bone marrow, blood, skin and certain other body tissues. Such cells have the ability to renew themselves and to develop into a more limited range of specialized cells. The main difference between the adult stem cells and the embryonic stem cells is that the former typically generate only the cell types of the tissue in which they reside while the latter can be induced to produce all types of cells. A blood-forming adult stem cell in the bone marrow, for example, is used to get the different types of blood cells such as red blood cells, white blood cells and platelets.

The Potential Benefits of Stem Cells: Bone marrow transplantation, which involves the transplantation of blood stem cells is a well-established therapy for a variety of blood diseases. Some of the other potential benefits of stem cell research are:

Basic Information About Cells: Stem cell research is likely to yield basic information about stem cell diffrentiation. If scientists can uncover the exact processes involved in cell division and the conversion of undifferentiated cells into differentiated cells, it may yield to finding cures for serious illnesess such as cancer and birth defects ("What are the Potential Uses of Human Stem cells?").

Cell-Based Therapies: The most important potential application of human stem cells is the generation of cells and tissues that could be used for cell-based therapies. If scientists can find a way to accurately direct stem cells to differentiate into specific cell types, it could lead to the treatment of diseases such as Parkinson's and Alzheimer's, spinal cord injury, stroke, burns, heart disease, diabetes, osteoarthritis, and rheumatoid arthritis. For example, it may become possible to produce healthy heart muscles in the lab and transplant them into patients with damaged hearts; or insulin-producing cells could be used to cure diabetics (Ibid.)

Drug Testing: Human stem cell research could also dramatically change the way drugs are developed and tested for safety. For example, new medications could initially be tested for safety using human cell lines prior to going into clinical trials (Ibid.).

The Ethical Debate

The ethical debate about stem cell research usually center on these 3 areas:

Is Embryo a Person? Since human embryos are destroyed when harvested for research, stem cell research has become entangled with the abortion debate. The opponents of stem cell research oppose the use of anything for research that is "viable," i.e., able to grow into a person and argue that it is wrong since it destroys human life. Supporters of the research point out that the frozen embryos kept in the fertility clinics by the thousands would either be eventually discarded or kept frozen indefinitely; hence there is no harm in using them for research. They also contend that embryos cannot be considered "life" at such an early stage ("Ethics, Moral Values, and the U.S. Law").

Reproductive Cloning. Stem cell research is also looked at with suspicion because of its similarity with reproductive cloning. Both processes involve the use of a lab technique called 'nuclear transfer' although in stem cell research the technique is used to grow replacement tissues that are genetically matched to specific patients rather than for creating human clones.

Human-Animal Chimeras. Chimeras -- the organisms composed of cells or tissues from more than one individual -- are considered essential for advancing stem cell research to viable therapies, since no therapy can be tested in humans without research in animals first. However, when human and animal cells are mixed in the laboratory, it becomes an ethical issue, which some people consider unacceptable (Ibid.).

Why Stem Cell Research is Important to the Society and the future of Science?

As we have seen in this paper so far, stem cell research can have far-reaching effects on the future of Science and the human society because of its potential to develop new disease models, alter the current drug development philosophy, and introduce new applications in transplantation medicine. However, there is consensus among scientists that considerable research is needed before the dream can become a reality and the scope of research can only be made possible through large-scale government (read U.S. federal government) funding.